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1. Very-high-energy γ-Ray Emission from Young Massive Star Clusters in the Large Magellanic Cloud

Author: F. Aharonian, F. Ait Benkhali, J. Aschersleben, H. Ashkar, M. Backes, V. Barbosa Martins, R. Batzofin, Y. Becherini, D. Berge, K. Bernlöhr, M. Böttcher, J. Bolmont, M. de Bony de Lavergne, J. Borowska, R. Brose, A. Brown, F. Brun, B. Bruno, C. Burger-Scheidlin, S. Casanova, J. Celic, M. Cerruti, T. Chand, S. Chandra, A. Chen, J. Chibueze, O. Chibueze, G. Cotter, P. Cristofari, J. Devin, A. Djannati-Ataï, J. Djuvsland, A. Dmytriiev, K. Egberts, S. Einecke, K. Feijen, M. Filipovic, G. Fontaine, S. Funk, S. Gabici, Y. A. Gallant, J. F. Glicenstein, J. Glombitza, G. Grolleron, L. Haerer, B. Heß, J. A. Hinton, W. Hofmann, T. L. Holch, D. Horns, Zhiqiu Huang, M. Jamrozy, F. Jankowsky, I. Jung-Richardt, E. Kasai, K. Katarzyński, R. Khatoon, B. Khélifi, W. Kluźniak, Nu. Komin, K. Kosack, D. Kostunin, A. Kundu, R. G. Lang, S. Le Stum, A. Lemière, M. Lemoine-Goumard, J.-P. Lenain, F. Leuschner, J. Mackey, V. Marandon, G. Martí-Devesa, R. Marx, A. Mehta, A. Mitchell, R. Moderski, M. O. Moghadam, L. Mohrmann, A. Montanari, E. Moulin, M. de Naurois, J. Niemiec, S. Ohm, L. Olivera-Nieto, E. de Ona Wilhelmi, M. Ostrowski, S. Panny, U. Pensec, G. Peron, G. Pühlhofer, A. Quirrenbach, S. Ravikularaman, M. Regeard, A. Reimer, O. Reimer, H. Ren, M. Renaud, B. Reville, F. Rieger, G. Rowell, B. Rudak, E. Ruiz-Velasco, K. Sabri, V. Sahakian, H. Salzmann, A. Santangelo, M. Sasaki, J. Schäfer, F. Schüssler, H. M. Schutte, H. Sol, S. Spencer, Ł. Stawarz, S. Steinmassl, C. Steppa, K. Streil, I. Sushch, A. M. Taylor, R. Terrier, M. Tsirou, N. Tsuji, C. van Eldik, M. Vecchi, C. Venter, J. Vink, S. J. Wagner, R. White, A. Wierzcholska, M. Zacharias, A. A. Zdziarski, A. Zech, N. Żywucka, and H.E.S.S. Collaboration
Subjects: Young star clusters, Massive stars, Large Magellanic Cloud, Gamma-ray astronomy, Astrophysics, QB460-466
Abstract: The Tarantula Nebula in the Large Magellanic Cloud is known for its high star formation activity. At its center lies the young massive star cluster R136, providing a significant amount of the energy that makes the nebula shine so brightly at many wavelengths. Recently, young massive star clusters have been suggested to also efficiently produce very high-energy cosmic rays, potentially beyond PeV energies. Here, we report the detection of very-high-energy γ -ray emission from the direction of R136 with the High Energy Stereoscopic System, achieved through a multicomponent, likelihood-based modeling of the data. This supports the hypothesis that R136 is indeed a very powerful cosmic-ray accelerator. Moreover, from the same analysis, we provide an updated measurement of the γ -ray emission from 30 Dor C, the only superbubble detected at TeV energies presently. The γ -ray luminosity above 0.5 TeV of both sources is (2–3) × 10 ^35 erg s ^−1 . This exceeds by more than a factor of 2 the luminosity of HESS J1646−458, which is associated with the most massive young star cluster in the Milky Way, Westerlund 1. Furthermore, the γ -ray emission from each source is extended with a significance of >3 σ and a Gaussian width of about 30 pc. For 30 Dor C, a connection between the γ -ray emission and the nonthermal X-ray emission appears likely. Different interpretations of the γ -ray signal from R136 are discussed.
Published: 2024
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2. ULTRASAT: A Wide-field Time-domain UV Space Telescope

Author: Y. Shvartzvald, E. Waxman, A. Gal-Yam, E. O. Ofek, S. Ben-Ami, D. Berge, M. Kowalski, R. Bühler, S. Worm, J. E. Rhoads, I. Arcavi, D. Maoz, D. Polishook, N. Stone, B. Trakhtenbrot, M. Ackermann, O. Aharonson, O. Birnholtz, D. Chelouche, D. Guetta, N. Hallakoun, A. Horesh, D. Kushnir, T. Mazeh, J. Nordin, A. Ofir, S. Ohm, D. Parsons, A. Pe’er, H. B. Perets, V. Perdelwitz, D. Poznanski, I. Sadeh, I. Sagiv, S. Shahaf, M. Soumagnac, L. Tal-Or, J. Van Santen, B. Zackay, O. Guttman, P. Rekhi, A. Townsend, A. Weinstein, and I. Wold
Subjects: Near ultraviolet astronomy, Space telescopes, Time domain astronomy, Gravitational wave sources, Supernovae, Gamma-ray bursts, Astrophysics, QB460-466
Abstract: The Ultraviolet Transient Astronomy Satellite (ULTRASAT) is scheduled to be launched to geostationary orbit in 2027. It will carry a telescope with an unprecedentedly large field of view (204 deg ^2 ) and near-ultraviolet (NUV; 230–290 nm) sensitivity (22.5 mag, 5 σ , at 900 s). ULTRASAT will conduct the first wide-field survey of transient and variable NUV sources and will revolutionize our ability to study the hot transient Universe. It will explore a new parameter space in energy and timescale (months-long light curves with minutes cadence), with an extragalactic volume accessible for the discovery of transient sources that is >300 times larger than that of the Galaxy Evolution Explorer (GALEX) and comparable to that of the Vera Rubin Observatory’s Legacy Survey of Space and Time. ULTRASAT data will be transmitted to the ground in real time, and transient alerts will be distributed to the community in 23.5 AB mag, over 10 times deeper than the GALEX map. Two key science goals of ULTRASAT are the study of mergers of binaries involving neutron stars, and supernovae. With a large fraction (>50%) of the sky instantaneously accessible, fast (minutes) slewing capability, and a field of view that covers the error ellipses expected from gravitational-wave (GW) detectors beyond 2026, ULTRASAT will rapidly detect the electromagnetic emission following binary neutron star/neutron star–black hole mergers identified by GW detectors, and will provide continuous NUV light curves of the events. ULTRASAT will provide early (hour) detection and continuous high-cadence (minutes) NUV light curves for hundreds of core-collapse supernovae, including for rarer supernova progenitor types.
Published: 2024
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3. The Vanishing of the Primary Emission Region in PKS 1510–089

Author: F. Aharonian, F. Ait Benkhali, J. Aschersleben, H. Ashkar, M. Backes, V. Barbosa Martins, J. Barnard, R. Batzofin, Y. Becherini, D. Berge, K. Bernlöhr, B. Bi, M. de Bony de Lavergne, M. Böttcher, C. Boisson, J. Bolmont, J. Borowska, M. Bouyahiaoui, F. Bradascio, M. Breuhaus, R. Brose, A. M. Brown, F. Brun, B. Bruno, T. Bulik, C. Burger-Scheidlin, S. Caroff, S. Casanova, R. Cecil, J. Celic, M. Cerruti, T. Chand, S. Chandra, A. Chen, J. Chibueze, O. Chibueze, G. Cotter, J. Damascene Mbarubucyeye, I. D. Davids, A. Djannati-Ataï, A. Dmytriiev, V. Doroshenko, K. Egberts, S. Einecke, J.-P. Ernenwein, S. Fegan, G. Fontaine, M. Füßling, S. Funk, S. Gabici, S. Ghafourizadeh, G. Giavitto, D. Glawion, J. F. Glicenstein, P. Goswami, G. Grolleron, L. Haerer, W. Hofmann, T. L. Holch, M. Holler, D. Horns, M. Jamrozy, F. Jankowsky, V. Joshi, I. Jung-Richardt, E. Kasai, K. Katarzyński, R. Khatoon, B. Khélifi, W. Kluźniak, Nu. Komin, K. Kosack, D. Kostunin, R. G. Lang, S. Le Stum, F. Leitl, A. Lemière, J.-P. Lenain, F. Leuschner, A. Luashvili, J. Mackey, V. Marandon, P. Marchegiani, G. Martí-Devesa, R. Marx, A. Mehta, M. Meyer, A. Mitchell, R. Moderski, L. Mohrmann, A. Montanari, E. Moulin, M. de Naurois, J. Niemiec, A. Priyana Noel, P. O’Brien, S. Ohm, L. Olivera-Nieto, E. de Ona Wilhelmi, M. Ostrowski, S. Panny, M. Panter, G. Peron, D. A. Prokhorov, G. Pühlhofer, M. Punch, A. Quirrenbach, P. Reichherzer, A. Reimer, O. Reimer, H. Ren, F. Rieger, G. Rowell, B. Rudak, H. Rueda Ricarte, E. Ruiz-Velasco, V. Sahakian, H. Salzmann, D. A. Sanchez, A. Santangelo, M. Sasaki, F. Schüssler, H. M. Schutte, U. Schwanke, J. N. S. Shapopi, H. Sol, A. Specovius, S. Spencer, Ł. Stawarz, R. Steenkamp, S. Steinmassl, C. Steppa, I. Sushch, H. Suzuki, T. Takahashi, T. Tanaka, R. Terrier, N. Tsuji, C. van Eldik, B. van Soelen, M. Vecchi, J. Veh, J. Vink, T. Wach, S. J. Wagner, A. Wierzcholska, M. Zacharias, D. Zargaryan, A. A. Zdziarski, A. Zech, S. Zouari, N. Żywucka, D. A. H. Buckley, J. Cooper, D. Groenewald, and H.E.S.S. Collaboration
Subjects: Blazars, Relativistic jets, Non-thermal radiation sources, Flat-spectrum radio quasars, Gamma-ray sources, Spectropolarimetry, Astrophysics, QB460-466
Abstract: In 2021 July, PKS 1510−089 exhibited a significant flux drop in the high-energy γ -ray (by a factor 10) and optical (by a factor 5) bands and remained in this low state throughout 2022. Similarly, the optical polarization in the source vanished, resulting in the optical spectrum being fully explained through the steady flux of the accretion disk and the broad-line region. Unlike the aforementioned bands, the very-high-energy γ -ray and X-ray fluxes did not exhibit a significant flux drop from year to year. This suggests that the steady-state very-high-energy γ -ray and X-ray fluxes originate from a different emission region than the vanished parts of the high-energy γ -ray and optical jet fluxes. The latter component has disappeared through either a swing of the jet away from the line of sight or a significant drop in the photon production efficiency of the jet close to the black hole. Either change could become visible in high-resolution radio images.
Published: 2023
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4. Constraints on the Intergalactic Magnetic Field Using Fermi-LAT and H.E.S.S. Blazar Observations

Author: F. Aharonian, J. Aschersleben, M. Backes, V. Barbosa Martins, R. Batzofin, Y. Becherini, D. Berge, B. Bi, M. Bouyahiaoui, M. Breuhaus, R. Brose, F. Brun, B. Bruno, T. Bulik, C. Burger-Scheidlin, T. Bylund, S. Caroff, S. Casanova, J. Celic, M. Cerruti, T. Chand, S. Chandra, A. Chen, J. Chibueze, O. Chibueze, G. Cotter, M. de Bony, K. Egberts, J.-P. Ernenwein, G. Fichet de Clairfontaine, M. Filipovic, G. Fontaine, M. Füssling, S. Funk, S. Gabici, S. Ghafourizadeh, G. Giavitto, D. Glawion, J. F. Glicenstein, P. Goswami, M.-H. Grondin, L. Haerer, T. L. Holch, M. Holler, D. Horns, M. Jamrozy, F. Jankowsky, V. Joshi, I. Jung-Richardt, E. Kasai, K. Katarzyński, R. Khatoon, B. Khélifi, W. Kluźniak, Nu. Komin, K. Kosack, D. Kostunin, R. G. Lang, S. Le Stum, F. Leitl, A. Lemière, J.-P. Lenain, F. Leuschner, T. Lohse, A. Luashvili, I. Lypova, J. Mackey, D. Malyshev, V. Marandon, P. Marchegiani, A. Marcowith, G. Martí-Devesa, R. Marx, M. Meyer, A. Mitchell, R. Moderski, L. Mohrmann, A. Montanari, E. Moulin, J. Muller, T. Murach, K. Nakashima, J. Niemiec, S. Ohm, L. Olivera-Nieto, E. de Ona Wilhelmi, S. Panny, M. Panter, R. D. Parsons, G. Peron, D. A. Prokhorov, H. Prokoph, G. Pühlhofer, M. Punch, A. Quirrenbach, P. Reichherzer, A. Reimer, O. Reimer, B. Reville, F. Rieger, G. Rowell, B. Rudak, E. Ruiz-Velasco, V. Sahakian, D. A. Sanchez, M. Sasaki, F. Schüssler, H. M. Schutte, U. Schwanke, J. N. S. Shapopi, H. Sol, S. Spencer, S. Steinmassl, H. Suzuki, T. Takahashi, T. Tanaka, A. M. Taylor, R. Terrier, C. Thorpe-Morgan, M. Tsirou, N. Tsuji, Y. Uchiyama, C. van Eldik, J. Veh, C. Venter, S. J. Wagner, R. White, A. Wierzcholska, Yu Wun Wong, M. Zacharias, D. Zargaryan, A. A. Zdziarski, S. Zouari, N. Żywucka, H.E.S.S. Collaboration, and Fermi-LAT Collaboration
Subjects: Active galaxies, High energy astrophysics, Extragalactic magnetic fields, Astrophysics, QB460-466
Abstract: Magnetic fields in galaxies and galaxy clusters are believed to be the result of the amplification of intergalactic seed fields during the formation of large-scale structures in the universe. However, the origin, strength, and morphology of this intergalactic magnetic field (IGMF) remain unknown. Lower limits on (or indirect detection of) the IGMF can be obtained from observations of high-energy gamma rays from distant blazars. Gamma rays interact with the extragalactic background light to produce electron−positron pairs, which can subsequently initiate electromagnetic cascades. The gamma-ray signature of the cascade depends on the IGMF since it deflects the pairs. Here we report on a new search for this cascade emission using a combined data set from the Fermi Large Area Telescope and the High Energy Stereoscopic System. Using state-of-the-art Monte Carlo predictions for the cascade signal, our results place a lower limit on the IGMF of B > 7.1 × 10 ^−16 G for a coherence length of 1 Mpc even when blazar duty cycles as short as 10 yr are assumed. This improves on previous lower limits by a factor of 2. For longer duty cycles of 10 ^4 (10 ^7 ) yr, IGMF strengths below 1.8 × 10 ^−14 G (3.9 × 10 ^−14 G) are excluded, which rules out specific models for IGMF generation in the early universe.
Published: 2023
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5. H.E.S.S. Follow-up Observations of GRB 221009A

Author: F. Aharonian, F. Ait Benkhali, J. Aschersleben, H. Ashkar, M. Backes, A. Baktash, V. Barbosa Martins, R. Batzofin, Y. Becherini, D. Berge, K. Bernlöhr, B. Bi, M. Böttcher, C. Boisson, J. Bolmont, M. de Bony de Lavergne, J. Borowska, M. Bouyahiaoui, F. Bradascio, M. Breuhaus, R. Brose, F. Brun, B. Bruno, T. Bulik, C. Burger-Scheidlin, S. Caroff, S. Casanova, J. Celic, M. Cerruti, T. Chand, S. Chandra, A. Chen, J. Chibueze, O. Chibueze, G. Cotter, S. Dai, J. Damascene Mbarubucyeye, J. Devin, A. Djannati-Ataï, A. Dmytriiev, V. Doroshenko, K. Egberts, S. Einecke, J.-P. Ernenwein, S. Fegan, G. Fichet de Clairfontaine, M. Filipovic, G. Fontaine, M. Füßling, S. Funk, S. Gabici, S. Ghafourizadeh, G. Giavitto, D. Glawion, J. F. Glicenstein, P. Goswami, G. Grolleron, M.-H. Grondin, J. A. Hinton, T. L. Holch, M. Holler, D. Horns, Zhiqiu Huang, M. Jamrozy, F. Jankowsky, V. Joshi, I. Jung-Richardt, E. Kasai, K. Katarzyński, R. Khatoon, B. Khélifi, W. Kluźniak, Nu. Komin, R. Konno, K. Kosack, D. Kostunin, R. G. Lang, S. Le Stum, F. Leitl, A. Lemière, M. Lemoine-Goumard, J.-P. Lenain, F. Leuschner, T. Lohse, I. Lypova, J. Mackey, D. Malyshev, V. Marandon, P. Marchegiani, A. Marcowith, G. Martí-Devesa, R. Marx, M. Meyer, A. Mitchell, L. Mohrmann, A. Montanari, E. Moulin, T. Murach, K. Nakashima, M. de Naurois, J. Niemiec, A. Priyana Noel, P. O’Brien, S. Ohm, L. Olivera-Nieto, E. de Ona Wilhelmi, M. Ostrowski, S. Panny, M. Panter, R. D. Parsons, G. Peron, D. A. Prokhorov, H. Prokoph, G. Pühlhofer, M. Punch, A. Quirrenbach, P. Reichherzer, A. Reimer, O. Reimer, H. Ren, M. Renaud, B. Reville, F. Rieger, G. Rowell, B. Rudak, E. Ruiz-Velasco, V. Sahakian, H. Salzmann, A. Santangelo, M. Sasaki, J. Schäfer, F. Schüssler, H. M. Schutte, U. Schwanke, J. N. S. Shapopi, A. Specovius, S. Spencer, Ł. Stawarz, R. Steenkamp, S. Steinmassl, C. Steppa, I. Sushch, H. Suzuki, T. Takahashi, T. Tanaka, R. Terrier, N. Tsuji, Y. Uchiyama, M. Vecchi, C. Venter, J. Vink, S. J. Wagner, R. White, A. Wierzcholska, Yu Wun Wong, M. Zacharias, D. Zargaryan, A. A. Zdziarski, A. Zech, S. J. Zhu, N. Żywucka, and H.E.S.S. Collaboration
Subjects: Gamma-rays, Gamma-ray bursts, Non-thermal radiation sources, High-energy cosmic radiation, Astrophysics, QB460-466
Abstract: GRB 221009A is the brightest gamma-ray burst (GRB) ever detected. To probe the very-high-energy (VHE; >100 GeV) emission, the High Energy Stereoscopic System (H.E.S.S.) began observations 53 hr after the triggering event, when the brightness of the moonlight no longer precluded observations. We derive differential and integral upper limits using H.E.S.S. data from the third, fourth, and ninth nights after the initial GRB detection, after applying atmospheric corrections. The combined observations yield an integral energy flux upper limit of ${{\rm{\Phi }}}_{\mathrm{UL}}^{95 \% }=9.7\times {10}^{-12}\,\mathrm{erg}\,{\mathrm{cm}}^{-2}\,{{\rm{s}}}^{-1}$ above E _thr = 650 GeV. The constraints derived from the H.E.S.S. observations complement the available multiwavelength data. The radio to X-ray data are consistent with synchrotron emission from a single electron population, with the peak in the spectral energy distribution occurring above the X-ray band. Compared to the VHE-bright GRB 190829A, the upper limits for GRB 221009A imply a smaller gamma-ray to X-ray flux ratio in the afterglow. Even in the absence of a detection, the H.E.S.S. upper limits thus contribute to the multiwavelength picture of GRB 221009A, effectively ruling out an IC-dominated scenario.
Published: 2023
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6. Background rejection in atmospheric Cherenkov telescopes using recurrent convolutional neural networks

Author: R. D. Parsons and S. Ohm
Subjects: Astrophysics, QB460-466, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract: Abstract In this work, we present a new, high performance algorithm for background rejection in imaging atmospheric Cherenkov telescopes. We build on the already popular machine-learning techniques used in gamma-ray astronomy by the application of the latest techniques in machine learning, namely recurrent and convolutional neural networks, to the background rejection problem. Use of these machine-learning techniques addresses some of the key challenges encountered in the currently implemented algorithms and helps to significantly increase the background rejection performance between 100 GeV and 100 TeV energies. We apply these machine learning techniques to the H.E.S.S. telescope array, first testing their performance on simulated data and then applying the analysis to two well known gamma-ray sources. With real observational data we find significantly improved performance over the current standard methods, with a 20–25% reduction in the background rate when applying the recurrent neural network analysis. Importantly, we also find that the convolutional neural network results are strongly dependent on the sky brightness in the source region which has important implications for the future implementation of this method in Cherenkov telescope analyses.
Published: 2020
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7. IVA for Visually Impaired People Using Raspberry PI

Author: Mr. S. Ohm Shankar
Subjects: General Medicine
Abstract: Disability is a condition in which a person must rely on others for their basic needs. One of a person's limitations is a visual impairment. To date, a number of ways for improving the lives of visually impaired and blind persons have been proposed. Purchasing groceries in the store without the assistance of others remains a difficult task for them. We offer a camera-based assistive text reading system that can help blind persons read text labels and product packaging on common objects. We rest present an ancient and active motion-based way to define a region of interest (ROI) in the video by requesting the user to shake the object to isolate it from cluttered backdrops or other surrounding objects in the camera view. Audio guidance based on realtime situations will aid them inside the supermarket. The ultimate goal of this system is to eliminate all other forms of assistance for visually impaired shoppers and to give them with a convenient and sophisticated environment. When this method is implemented, it makes shopping easier for blind people, saves time for customers, and increases business sales. We look at user interface difficulties and evaluate the algorithm's ability to extract and read text from objects with complex backgrounds. In this Shopping trolley technology to identify the product placed due to machine learning and accuracy location
Published: 2022

8. A MeerKAT, e-MERLIN, HESS, and Swift search for persistent and transient emission associated with three localized FRBs

Author: J O Chibueze, M Caleb, L Spitler, H Ashkar, F Schüssler, B W Stappers, C Venter, I Heywood, A M S Richards, D R A Williams, M Kramer, R Beswick, M C Bezuidenhout, R P Breton, L N Driessen, F Jankowski, E F Keane, M Malenta, M Mickaliger, V Morello, H Qiu, K Rajwade, S Sanidas, M Surnis, T W Scragg, C R H Walker, N Wrigley, H E S S Collaboration: F Aharonian, F Ait Benkhali, E O Angüner, M Backes, V Baghmanyan, V Barbosa Martins, R Batzofin, Y Becherini, D Berge, M Böttcher, C Boisson, J Bolmont, M de Bony de Lavergne, M Breuhaus, R Brose, F Brun, T Bulik, F Cangemi, S Caroff, S Casanova, J Catalano, M Cerruti, T Chand, A Chen, O U Chibueze, G Cotter, P Cristofari, J Damascene Mbarubucyeye, J Devin, A Djannati-Ataï, A Dmytriiev, K Egberts, J-P Ernenwein, A Fiasson, G Fichet de Clairfontaine, G Fontaine, S Funk, S Gabici, S Ghafourizadeh, G Giavitto, D Glawion, M-H Grondin, M Hörbe, C Hoischen, T L Holch, Zhiqiu Huang, M Jamrozy, F Jankowsky, V Joshi, I Jung-Richardt, E Kasai, K Katarzyński, U Katz, B Khélifi, W Kluźniak, Nu Komin, K Kosack, D Kostunin, A Lemière, J-P Lenain, F Leuschner, T Lohse, A Luashvili, I Lypova, J Mackey, D Malyshev, V Marandon, P Marchegiani, A Marcowith, G Martí-Devesa, R Marx, A Mitchell, R Moderski, L Mohrmann, E Moulin, J Muller, K Nakashima, M de Naurois, A Nayerhoda, J Niemiec, A Priyana Noel, P O’Brien, S Ohm, L Olivera-Nieto, E de Ona Wilhelmi, M Ostrowski, S Panny, R D Parsons, S Pita, V Poireau, D A Prokhorov, H Prokoph, G Pühlhofer, A Quirrenbach, P Reichherzer, A Reimer, O Reimer, G Rowell, B Rudak, E Ruiz-Velasco, V Sahakian, S Sailer, H Salzmann, D A Sanchez, A Santangelo, M Sasaki, H M Schutte, U Schwanke, J N S Shapopi, A Specovius, S Spencer, R Steenkamp, S Steinmassl, T Takahashi, T Tanaka, C Thorpe-Morgan, N Tsuji, C van Eldik, J Veh, J Vink, S J Wagner, A Wierzcholska, Yu Wun Wong, A Yusafzai, M Zacharias, D Zargaryan, A A Zdziarski, A Zech, S J Zhu, S Zouari, N Żywucka, High Energy Astrophys. & Astropart. Phys (API, FNWI), Centre de Physique des Particules de Marseille (CPPM), Aix Marseille Université (AMU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), AstroParticule et Cosmologie (APC (UMR_7164)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Laboratoire Univers et Théories (LUTH (UMR_8102)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE (UMR_7585)), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Annecy de Physique des Particules (LAPP), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Université de Bordeaux (UB), Laboratoire Univers et Particules de Montpellier (LUPM), and Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)
Subjects: radio continuum: galaxies, High Energy Astrophysical Phenomena (astro-ph.HE), ) fast radio burst [(transients], FOS: Physical sciences, Astronomy and Astrophysics, radiation mechanisms: non-thermal, non-thermal [radiation mechanisms], Astrophysics - Astrophysics of Galaxies, galaxies [radio continuum], fast radio bursts, Space and Planetary Science, [SDU]Sciences of the Universe [physics], Astrophysics of Galaxies (astro-ph.GA), (transients:) fast radio burst, ddc:520, Astrophysics - High Energy Astrophysical Phenomena
Abstract: Monthly notices of the Royal Astronomical Society 515(1), 1365 - 1379 (2022). doi:10.1093/mnras/stac1601, We report on a search for persistent radio emission from the one-off fast radio burst (FRB) 20190714A, as well as from two repeating FRBs, 20190711A and 20171019A, using the MeerKAT radio telescope. For FRB 20171019A, we also conducted simultaneous observations with the High-Energy Stereoscopic System (H.E.S.S.) in very high-energy gamma rays and searched for signals in the ultraviolet, optical, and X-ray bands. For this FRB, we obtain a UV flux upper limit of |$1.39 \times 10^{-16}~{\rm erg\, cm^{-2}\, s^{-1}}$|Å^−1, X-ray limit of |$\sim 6.6 \times 10^{-14}~{\rm erg\, cm^{-2}\, s^{-1}}$| and a limit on the very high energy gamma-ray flux |$\Phi (E\gt 120\, {\rm GeV}) \lt 1.7\times 10^{-12}\, \mathrm{erg\, cm^{-2}\, s^{-1}}$|⁠. We obtain a radio upper limit of ∼15 |$\mu$|Jy beam^−1 for persistent emission at the locations of both FRBs 20190711A and 20171019A with MeerKAT. However, we detected an almost unresolved (ratio of integrated flux to peak flux is ∼1.7 beam) radio emission, where the synthesized beam size was ∼ 8 arcsec size with a peak brightness of |$\sim 53\, \mu$|Jy beam^−1 at MeerKAT and |$\sim 86\, \mu$|Jy beam^−1 at e-MERLIN, possibly associated with FRB 20190714A at z = 0.2365. This represents the first detection of persistent continuum radio emission potentially associated with a (as-yet) non-repeating FRB. If the association is confirmed, one of the strongest remaining distinction between repeaters and non-repeaters would no longer be applicable. A parallel search for repeat bursts from these FRBs revealed no new detections down to a fluence of 0.08 Jy ms for a 1 ms duration burst., Published by Oxford Univ. Press, Oxford
Published: 2023
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9. Sensitivity of the Cherenkov Telescope Array to TeV photon emission from the Large Magellanic Cloud

Author: A Acharyya, R Adam, A Aguasca-Cabot, I Agudo, A Aguirre-Santaella, J Alfaro, R Aloisio, R Alves Batista, E Amato, E O Angüner, C Aramo, C Arcaro, K Asano, J Aschersleben, H Ashkar, M Backes, A Baktash, C Balazs, M Balbo, J Ballet, A Bamba, A Baquero Larriva, V Barbosa Martins, U Barres de Almeida, J A Barrio, D Bastieri, P Batista, I Batkovic, J R Baxter, J Becerra González, J Becker Tjus, W Benbow, E Bernardini, M I Bernardos Martín, J Bernete Medrano, A Berti, B Bertucci, V Beshley, P Bhattacharjee, S Bhattacharyya, C Bigongiari, A Biland, E Bissaldi, F Bocchino, P Bordas, J Borkowski, E Bottacini, M Böttcher, F Bradascio, A M Brown, A Bulgarelli, L Burmistrov, S Caroff, A Carosi, E Carquín, S Casanova, E Cascone, F Cassol, M Cerruti, P Chadwick, S Chaty, A Chen, A Chiavassa, L Chytka, V Conforti, J Cortina, A Costa, H Costantini, G Cotter, S Crestan, P Cristofari, F D’Ammando, M Dalchenko, F Dazzi, A De Angelis, V De Caprio, E M de Gouveia Dal Pino, D De Martino, M de Naurois, V de Souza, M V del Valle, A G Delgado Giler, C Delgado, D della Volpe, D Depaoli, T Di Girolamo, A Di Piano, F Di Pierro, R Di Tria, L Di Venere, S Diebold, M Doro, D Dumora, V V Dwarkadas, C Eckner, K Egberts, G Emery, J Escudero, D Falceta-Goncalves, E Fedorova, S Fegan, Q Feng, D Ferenc, G Ferrand, E Fiandrini, M Filipovic, V Fioretti, L Foffano, G Fontaine, Y Fukui, D Gaggero, G Galanti, G Galaz, S Gallozzi, V Gammaldi, M Garczarczyk, C Gasbarra, D Gasparrini, A Ghalumyan, M Giarrusso, G Giavitto, N Giglietto, F Giordano, A Giuliani, J-F Glicenstein, P Goldoni, J Goulart Coelho, J Granot, D Green, J G Green, M-H Grondin, O Gueta, D Hadasch, P Hamal, T Hassan, K Hayashi, M Heller, S Hernández Cadena, N Hiroshima, B Hnatyk, R Hnatyk, W Hofmann, J Holder, M Holler, D Horan, P Horvath, M Hrabovsky, M Hütten, M Iarlori, T Inada, F Incardona, S Inoue, F Iocco, M Jamrozy, W Jin, I Jung-Richardt, J Juryšek, D Kantzas, V Karas, H Katagiri, D Kerszberg, J Knödlseder, N Komin, P Kornecki, K Kosack, G Kowal, H Kubo, A Lamastra, J Lapington, M Lemoine-Goumard, J-P Lenain, F Leone, G Leto, F Leuschner, E Lindfors, T Lohse, S Lombardi, F Longo, R López-Coto, A López-Oramas, S Loporchio, P L Luque-Escamilla, O Macias, P Majumdar, D Mandat, S Mangano, G Manicò, M Mariotti, P Marquez, G Marsella, J Martí, P Martin, M Martínez, D Mazin, S Menchiari, D M-A Meyer, D Miceli, M Miceli, J Michałowski, A Mitchell, R Moderski, L Mohrmann, M Molero, E Molina, T Montaruli, A Moralejo, D Morcuende, A Morselli, E Moulin, V Moya, R Mukherjee, K Munari, A Muraczewski, S Nagataki, T Nakamori, A Nayak, J Niemiec, M Nievas, M Nikołajuk, K Nishijima, K Noda, D Nosek, B Novosyadlyj, S Nozaki, M Ohishi, S Ohm, A Okumura, B Olmi, R A Ong, M Orienti, R Orito, M Orlandini, E Orlando, S Orlando, M Ostrowski, I Oya, A Pagliaro, M Palatka, F R Pantaleo, R Paoletti, J M Paredes, N Parmiggiani, B Patricelli, M Pech, M Pecimotika, M Persic, O Petruk, E Pierre, E Pietropaolo, G Pirola, M Pohl, E Prandini, C Priyadarshi, G Pühlhofer, M L Pumo, M Punch, F S Queiroz, A Quirrenbach, S Rainò, R Rando, S Razzaque, A Reimer, O Reimer, T Reposeur, M Ribó, T Richtler, J Rico, F Rieger, M Rigoselli, V Rizi, E Roache, G Rodriguez Fernandez, P Romano, G Romeo, J Rosado, A Rosales de Leon, B Rudak, C Rulten, I Sadeh, T Saito, M Sánchez-Conde, H Sano, A Santangelo, R Santos-Lima, S Sarkar, F G Saturni, A Scherer, P Schovanek, F Schussler, U Schwanke, O Sergijenko, M Servillat, H Siejkowski, C Siqueira, S Spencer, A Stamerra, S Stanič, C Steppa, T Stolarczyk, Y Suda, T Tavernier, M Teshima, L Tibaldo, D F Torres, N Tothill, M Vacula, B Vallage, P Vallania, C van Eldik, M Vázquez Acosta, M Vecchi, S Ventura, S Vercellone, A Viana, C F Vigorito, J Vink, V Vitale, V Vodeb, S Vorobiov, T Vuillaume, S J Wagner, R Walter, M White, A Wierzcholska, M Will, R Yamazaki, L Yang, T Yoshikoshi, M Zacharias, G Zaharijas, D Zavrtanik, M Zavrtanik, A A Zdziarski, V I Zhdanov, K Ziętara, M Živec, Joseph Louis LAGRANGE (LAGRANGE), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Leprince-Ringuet (LLR), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Astrophysique Interprétation Modélisation (AIM (UMR7158 / UMR_E_9005 / UM_112)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Annecy de Physique des Particules (LAPP), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Centre de Physique des Particules de Marseille (CPPM), Aix Marseille Université (AMU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), AstroParticule et Cosmologie (APC (UMR_7164)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Galaxies, Etoiles, Physique, Instrumentation (GEPI), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Annecy-le-Vieux de Physique Théorique (LAPTH), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Institut de recherche en astrophysique et planétologie (IRAP), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE (UMR_7585)), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), and Cherenkov Telescope Array
Subjects: High Energy Astrophysical Phenomena (astro-ph.HE), photon, emission, acceleration, efficiency, Cherenkov Telescope Array, WIMP, diffusion, FOS: Physical sciences, Astronomy and Astrophysics, suppression, sensitivity, Navarro-Frenk-White profile, dark matter, photon, energy, flux, cosmic radiation, spectrum, energy, high, Space and Planetary Science, cloud, TeV, spectral, galaxy, Astrophysics - High Energy Astrophysical Phenomena, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], nucleus, cosmic radiation
Abstract: A deep survey of the Large Magellanic Cloud at ~0.1-100TeV photon energies with the Cherenkov Telescope Array is planned. We assess the detection prospects based on a model for the emission of the galaxy, comprising the four known TeV emitters, mock populations of sources, and interstellar emission on galactic scales. We also assess the detectability of 30 Doradus and SN 1987A, and the constraints that can be derived on the nature of dark matter. The survey will allow for fine spectral studies of N157B, N132D, LMC P3, and 30 Doradus C, and half a dozen other sources should be revealed, mainly pulsar-powered objects. The remnant from SN 1987A could be detected if it produces cosmic-ray nuclei with a flat power-law spectrum at high energies, or with a steeper index 2.3-2.4 pending a flux increase by a factor >3-4 over ~2015-2035. Large-scale interstellar emission remains mostly out of reach of the survey if its >10GeV spectrum has a soft photon index ~2.7, but degree-scale 0.1-10TeV pion-decay emission could be detected if the cosmic-ray spectrum hardens above >100GeV. The 30 Doradus star-forming region is detectable if acceleration efficiency is on the order of 1-10% of the mechanical luminosity and diffusion is suppressed by two orders of magnitude within, Accepted for publication in MNRAS. Corresponding authors: Pierrick Martin, Maria Isabel Bernardos Martin, Fabio Iocco
Published: 2023

10. IVA for Visually Impaired People Using Raspberry PI

Author: Shankar, Mr. S. Ohm, primary
Published: 2022
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11. Cherenkov Telescope Array : the World’s largest VHE gamma-ray observatory

Author: Roberta Zanin, H. Abdalla, H. Abe, S. Abe, A. Abusleme, F. Acero, A. Acharyya, V. Acin Portella, K. Ackley, R. Adam, C. Adams, S.S. Adhikari, I. Aguado Ruesga, I. Agudo, R. Aguilera, A. Aguirre Santaella, F. Aharonian, A. Alberdi, R. Alfaro, J. Alfaro, C. Alispach, R. Aloisio, R. Alves Batista, J.P. Amans, L. Amati, E. Amato, L. Ambrogi, G. Ambrosi, M. Ambrosio, R. Ammendola, J. Anderson, M. Anduze, E.O. Anguner, L.A. Antonelli, V. Antonuccio, P. Antoranz, R. Anutarawiramkul, J. Aragunde Gutierrez, C. Aramo, A. Araudo, M. Araya, A. Arbet Engels, C. Arcaro, V. Arendt, C. Armand, T. Armstrong, F. Arqueros, L. Arrabito, B. Arsioli, M. Artero, K. Asano, Y. Ascasibar, J. Aschersleben, M. Ashley, P. Attina, P. Aubert, C. B. Singh, D. Baack, A. Babic, M. Backes, V. Baena, S. Bajtlik, A. Baktash, C. Balazs, M. Balbo, O. Ballester, J. Ballet, B. Balmaverde, A. Bamba, R. Bandiera, A. Baquero Larriva, P. Barai, C. Barbier, V. Barbosa Martins, M. Barcelo, M. Barkov, M. Barnard, L. Baroncelli, U. Barres de Almeida, J.A. Barrio, D. Bastieri, P.I. Batista, I. Batkovic, C. Bauer, R. Bautista González, J. Baxter, U. Becciani, J. Becerra González, Y. Becherini, G. Beck, J. Becker Tjus, W. Bednarek, A. Belfiore, L. Bellizzi, R. Belmont, W. Benbow, D. Berge, E. Bernardini, M.I. Bernardos, K. Bernlöhr, A. Berti, M. Berton, B. Bertucci, V. Beshley, N. Bhatt, S. Bhattacharyya, W. Bhattacharyya, B. Y. Bi, G. Bicknell, N. Biederbeck, C. Bigongiari, A. Biland, R. Bird, E. Bissaldi, J. Biteau, M. Bitossi, O. Blanch, M. Blank, J. Blazek, J. Bobin, C. Boccato, F. Bocchino, C. Boehm, M. Bohacova, C. Boisson, J. Boix, J.P. Bolle, J. Bolmont, G. Bonanno, C. Bonavolontà, L. Bonneau Arbeletche, G. Bonnoli, P. Bordas, J. Borkowski, R. Bose, D. Bose, Z. Bosnjak, E. Bottacini, Markus Böttcher, M.T. Botticella, C. Boutonnet, F. Bouyjou, V. Bozhilov, E. Bozzo, L. Brahimi, C. Braiding, S. Brau Nogue, S. Breen, J. Bregeon, M. Breuhaus, A. Brill, W. Brisken, E. Brocato, A.M. Brown, K. Brügge, P. Brun, F. Brun, L. Brunetti, G. Brunetti, P. Bruno, A. Bruno, A. Bruzzese, N. Bucciantini, J. H. Buckley, R. Bühler, A. Bulgarelli, T. Bulik, M. Bünning, M. Bunse, M. Burton, A. Burtovoi, M. Buscemi, S. Buschjager, G. Busetto, J. Buss, K. Byrum, A. Caccianiga, F. Cadoux, A. Calanducci, C. Calderon, J. Calvo Tovar, R. A. Cameron, P. Campana, R. Canestrari, F. Cangemi, B. Cantlay, M. Capalbi, M. Capasso, M. Cappi, A. Caproni, R. Capuzzo Dolcetta, P. Caraveo, V. Cárdenas, L. Cardiel, M. Cardillo, C. Carlile, S. Caroff, R. Carosi, A. Carosi, E. Carquin, M. Carrere, J.M. Casandjian, S. Casanova, F. Cassol, F. Catalani, O. Catalano, D. Cauz, A. Ceccanti, C. Celestino Silva, K. Cerny, M. Cerruti, E. Chabanne, P. Chadwick, Y. Chai, P. Chambery, C. Champion, S. Chaty, A. Chen, K. Cheng, M. Chernyakova, G. Chiaro, A. Chiavassa, M. Chikawa, V.R. Chitnis, J. Chudoba, L. Chytka, S. Cikota, A. Circiello, P. Clark, M. Colak, E. Colombo, S. Colonges, A. Comastri, A. Compagnino, V. Conforti, E. Congiu, R. Coniglione, J. Conrad, F. Conte, J.L. Contreras, P. Coppi, R. Cornat, J. Coronado Blazquez, J. Cortina, A. Costa, H. Costantini, G. Cotter, B. Courty, S. Covino, S. Crestan, P. Cristofari, R. Crocker, J. Croston, K. Cubuk, O. Cuevas, X. Cui, G. Cusumano, S. Cutini, G. D'Amico, F. D'Ammando, P. D'Avanzo, P. Da Vela, M. Dadina, S. Dai, M. Dalchenko, M. Dall'Ora, M.K. Daniel, J. Dauguet, I. Davids, J. Davies, B. Dawson, A. De Angelis, A.E. de Araujo Carvalho, M. de Bony de Lavergne, G. De Cesare, F. de Frondat, I. de la Calle, E. de Gouveia Dal Pino, B. De Lotto, A. De Luca, D. De Martino, M. de Naurois, E. de Ona Wilhelmi, F. De Palma Persio, N. De Simone, V. de Souza Valle, E. Delagnes, G. Deleglise Reznicek, C. Delgado, A.G. Delgado Giler, J. Delgado Mengual Valle, Domenico Della Volpe, D. Depaoli, J. Devin, T. Di Girolamo, C. Di Giulio Pierro, L. Di Venere, C. Díaz, C. Dib, S. Diebold, S. Digel, A. Djannati Atai, J. Djuvsland, A. Dmytriiev, K. Docher, A. Domínguez, D. Dominis Prester, A. Donini, D. Dorner, M. Doro, Rita Cassia dos Anjos, J.L. Dournaux, T. Downes, G. Drake, H. Drass, D. Dravins, C. Duangchan, A. Duara, G. Dubus, L. Ducci, C. Duffy, D. Dumora, K. Dundas Mora, A. Durkalec, V.V. Dwarkadas, J. Ebr, C. Eckner, J. Eder, E. Edy, K. Egberts, S. Einecke, C. Eleftheriadis, D. Elsässer, G. Emery, D. Emmanoulopoulos, J.P. Ernenwein, M. Errando, P. Escarate, J. Escudero, C. Espinoza, S. Ettori, A. Eungwanichayapant, P. Evans, C. Evoli, M. Fairbairn, D. Falceta Goncalves, A. Falcone, V. Fallah Ramazanı, R. Falomo, K. Farakos, G. Fasola, A. Fattorini, Y. Favre, R. Fedora, E. Fedorova, K. Feijen, Q. Feng, G. Ferrand, G. Ferrara, O. Ferreira, M. Fesquet, E. Fiandrini, A. Fiasson, M. Filipovic, D. Fink, J.P. Finley, V. Fioretti, D.F.G. Fiorillo, M. Fiorini, S. Flis, H. Flores, L. Foffano, C. Fohr, M.V. Fonseca, L. Font, G. Fontaine, O. Fornieri, P. Fortin, L. Fortson, N. Fouque, B. Fraga, A. Franceschini, F.J. Franco, L. Freixas Coromina, L. Fresnillo, D. Fugazza, Y. Fujita, S. Fukami, Y. Fukazawa, D. Fulla, S. Funk, A. Furniss, S. Gabici, D. Gaggero, G. Galanti, P. Galdemard, Y. A. Gallant, D. Galloway, S. Gallozzi, V. Gammaldi, R. Garcia, L. E. García-Muñoz, E. Garcia Lopez, F. Gargano, C. Gargano, S. Garozzo, D. Gascon, T. Gasparetto, D. Gasparrini, H. Gasparyan, M. Gaug, N. Geffroy, A. Gent, S. Germani, A. Ghalumyan, A. Ghedina, G. Ghirlanda, F. Gianotti, S. Giarrusso, M. Giarrusso, G. Giavitto, B. Giebels, N. Giglietto, V. Gika, F. Gillardo, R. Gimenes, F. Giordano, E. Giro, M. Giroletti, Andrea Giuliani, M. Gjaja, J.F. Glicenstein, P. Gliwny, H. Goksu, P. Goldoni, J.L. Gomez, M.M. Gonzalez, Juan Manuel Gonzalez, K.S. Gothe, D. Gotz Coelho, T. Grabarczyk, R. Graciani, P. Grandi, G. Grasseau, D. Grasso, D. Green, J. Green, T. Greenshaw, P. Grespan, A. Grillo, M.H. Grondin, J. Grube, V. Guarino, B. Guest, O. Gueta, M. Günduz, S. Gunji, G. Gyuk, J. Hackfeld, D. Hadasch, L. Hagge, A. Hahn, J.E. Hajlaoui, A. Halim, P. Hamal, W. Hanlon, Y. Harada, M.J. Hardcastle, M. Harvey Collado, T. Haubold, A. Haupt, M. Havelka, K. Hayashi, M. Hayashida, H. He, L. Heckmann, M. Heller, F. Henault, Gilles Henri, G. Hermann, S. Hernández Cadena, J. Herrera Llorente, O. Hervet, J. Hinton, A. Hiramatsu, K. Hirotani, B. Hnatyk, R. Hnatyk, J.K. Hoang, D. H.H. Hoffmann, C. Hoischen, J. Holder, M. Holler, B. Hona, D. Horan, Dieter Horns, P. Horvath, J. Houles, M. Hrabovsky, D. Hrupec, Y. Huang, J.‑M. Huet, G. Hughes, G. Hull, T.B. Humensky, M. Hütten, M. Iarlori, J.M. Illa, R. Imazawa, T. Inada, F. Incardona, A. Ingallinera, S. Inoue, T. Inoue, Y. Inoue, F. Iocco, K. Ioka, M. Ionica, S. Iovenitti, A. Iriarte, K. Ishio, W. Ishizaki, Y. Iwamura, J. Jacquemier, M. Jacquemont, M. Jamrozy, P. Janecek, F. Jankowsky, A. JardinBlicq, C. Jarnot, P. Jean Martínez, L. Jocou, N. Jordana, M. Josselin, I. JungRichardt, F.J.P.A. Junqueira, C. Juramy Gilles, P. Kaaret, L.H.S. Kadowaki, M. Kagaya, R. Kankanyan, D. Kantzas, V. Karas, A. Karastergiou, S. Karkar, J. Kasperek, H. Katagiri, J. Kataoka, K. Katarzynski, S. Katsuda, N. Kawanaka, D. Kazanas, D. Kerszberg, B. Khélifi, M.C. Kherlakian, T.P. Kian, D.B. Kieda, T. Kihm, S. Kim, S. Kisaka, R. Kissmann, R. Kleijwegt, G. Kluge, W. Kluźniak, J. Knapp, A. Kobakhidze, Y. Kobayashi, B. Koch, J. Kocot, K. Kohri, N. Komin, A. Kong, K. Kosack, F. Krack, M. Krause, F. Krennrich, H. Kubo, V. N. Kudryavtsev, S. Kunwar, J. Kushida, P. Kushwaha, Barbera Parola, G. La Rosa, R. Lahmann, A. Lamastra, M. Landoni, D. Landriu, R.G. Lang, J. Lapington, P. Laporte, P. Lason, J. Lasuik, J. Lazendic Galloway, T. Le Flour, P. Le Sidaner, S. Leach, S.H. Lee, W.H. Lee, S. Lee Oliveira, A. Lemiere, M. Lemoine Goumard, J.P. Lenain, F. Leone, V. Leray, G. Leto, F. Leuschner, R. Lindemann, E. Lindfors, L. Linhoff, I. Liodakis, A. Lipniacka, M. Lobo, Thomas Lohse, S. Lombardi, A. Lopez, M. Lopez, R. Lopez Coto, F. Louis, M. Louys, F. Lucarelli, H. Ludwig Boudi, P.L. Luque Escamilla, M.C. Maccarone, E. Mach, A.J. Maciejewski, J. Mackey, P. Maeght, C. Maggio, G. Maier, P. Majumdar, M. Makariev, M. Mallamaci, R. Malta Nunes de Almeida, D. Malyshev, D. Mandat, G. Maneva, M. Manganaro, P. Manigot, K. Mannheim, N. Maragos, D. Marano, M. Marconi, A. Marcowith, M. Marculewicz, B. Marcun, J. Marin, N. Marinello, P. Marinos, S. Markoff, P. Marquez, G. Marsella, J. M. Martin, P. G. Martin, M. Martinez, G. Martinez, O. Martinez, H. Martinez Huerta, C. Marty, R. Marx, N. Masetti, P. Massimino, H. Matsumoto, N. Matthews, G. Maurin, W. Max Moerbeck, N. Maxted, M.N. Mazziotta, S.M. Mazzola, J.D. Mbarubucyeye, L. Mc Comb, I. McHardy, S. McKeague, S. McMuldroch, E. Medina, D. Medina Miranda, A. Melandri, C. Melioli, D. Melkumyan, S. Menchiari, S. Mereghetti, G. Merino Arevalo, E. Mestre, J.L. Meunier, T. Meures, S. Micanovic, M. Miceli, M. Michailidis, J. Michalowski, T. Miener, I. Mievre, J. D. Miller, T. Mineo, M. Minev, J.M. Miranda, A. Mitchell, T. Mizuno, B. A. Mode, R. Moderski, L. Mohrmann, E. Molinari, T. Montaruli, I. Monteiro, C. Moore, A. Moralejo, D. Morcuende Parrilla, E. Moretti, K. Mori, P. Moriarty, K. Morik, P. Morris, A. Morselli, K. Mosshammer, R. Mukherjee, J. Muller, C. Mundell, J. Mundet, T. Murach, A. Muraczewski, H. Muraishi, I. Musella, A. Musumarra, A. Nagai, S. Nagataki, T. Naito, T. Nakamori, K. Nakashima, K. Nakayama, N. Nakhjiri, G. Naletto, D. Naumann, L. Nava, M.A. Nawaz, H. Ndiyavala, D. Neise, L. Nellen, R. Nemmen, N. Neyroud, K. Ngernphat, T. Nguyen Trung, L. Nicastro, L. Nickel, J. Niemiec, D. Nieto, C. Nigro, M. Nikołajuk, D. Ninci, K. Noda, Y. Nogami, S. Nolan, R. P. Norris, D. Nosek, M. Nöthe, V. Novotny, S. Nozaki, F. Nunio, P. O'Brien, K. Obara, Y. Ohira, M. Ohishi, S. Ohm, T. Oka, N. Okazaki, A. Okumura, C. Oliver, G. Olivera, B. Olmi, M. Orienti, R. Orito, M. Orlandini, E. Orlando, J.P. Osborne, M. Ostrowski, N. Otte, E. Ovcharov, E. Owen, I. Oya, A. Ozieblo, M. Padovani, A. Pagliaro, A. Paizis, M. Palatiello, M. Palatka, E. Palazzi, J.‑L. Panazol, D. Paneque, S. Panny, Francesca Romana Pantaleo, M. Panter, M. Paolillo, A. Papitto, A. Paravac, J.M. Paredes, G. Pareschi, N. Parmiggiani, R.D. Parsons, P. Paśko, S. R. Patel, B. Patricelli, L. Pavletic, S. Pavy, A. Peer, M. Pecimotika, M.G. Pellegriti, P. Peñil Del Campo, A. Pepato, S. Perard, C. Perennes, M. Peresano, A. Perez Aguilera, J. Perez Romero, M.A. Perez Torres, M. Persic, P. O. Petrucci, O. Petruk, B. Peyaud, K. Pfrang, E. Pian, P. Piatteli, E. Pietropaolo, R. Pillera, D. Pimentel, F. Pintore, C. Pio Garcia, G. Pirola, F. Piron, S. Pita, M. Pohl, V. Poireau, A. Pollo, M. Polo, C. Pongkitivanichkul, J. Porthault, J. Powell, D. Pozo, R.R. Prado, E. Prandini, J. Prast, K. Pressard, G. Principe, N. Produit, D. Prokhorov, H. Prokoph, H. Przybilski, E. Pueschel, G. Pühlhofer, I. Puljak, M.L. Pumo, M. Punch, F. Queiroz, J. Quinn, A. Quirrenbach, P.J. Rajda, R. Rando, S. Razzaque, S. Recchia, P. Reichherzer, O. Reimer, A. Reisenegger, Q. Remy, M. Renaud, T. Reposeur, B. Reville, J.M. Reymond, J. Reynolds, D. Ribeiro, M. Ribo, G. Richards, J. Rico, F. Rieger, L. Riitano, M. Riquelme, D. Riquelme, S. Rivoire, V. Rizi, E. Roache, M. Roche, J. Rodriguez, G. Rodriguez Fernandez, J.C. Rodriguez Ramirez, J.J. Rodriguez Vazquez, G. Rojas, P. Romano, G. Romeo Lobato, C. Romoli, M. Roncadelli, J. Rosado, A. Rosales de Leon, G. Rowell, A. Rugliancich, J.E. Ruiz del Mazo, C. Rulten, C. Russell, F. Russo Hatlen, S. Safi Harb, L. Saha, V. Sahakian, S. Sailer, T. Saito, N. Sakaki, S. Sakurai, G. Salina, H. Salzmann, D. Sanchez, H. Sandaker, A. Sandoval, P. Sangiorgi, M. Sanguillon, H. Sano, M. Santander, A. Santangelo, R. Santos Lima, A. Sanuy, L. Sapozhnikov, T. Saric, S. Sarkar, H. Sasaki, N. Sasaki, Y. Sato, F.G. Saturni, M. Sawada, J. Schaefer, A. Scherer, J. Scherpenberg, P. Schipani, B. Schleicher, J. Schmoll, M. Schneider, H. Schoorlemmer, P. Schovanek, F. Schussler, B. Schwab, U. Schwanke, J. Schwarz, E. Sciacca, S. Scuderi, M. Seglar Arroyo, I. Seitenzahl, D. Semikoz, O. Sergijenko, J.E. Serna Franco, Karol Seweryn, V. Sguera, A. Shalchi, R.Y. Shang, P. Sharma, L. Sidoli, J. Sieiro, H. Siejkowski, A. Sillanpaa, B.B. Singh, K.K. Singh, A. Sinha, C. Siqueira, J. Sitarek, P. Sizun, V. Sliusar, D. Sobczynska, R.W. Sobrinho, H. Sol, G. Sottile, H. Spackman, S. Spencer, G. Spengler, D. Spiga, W. Springer, A. Stamerra, S. Stanic, R. Starling, Ł. Stawarz, Stanislav Stefanik, C. Stegmann, A. Steiner, S. Steinmassl, C. Stella, R. Sternberger, M. Sterzel, C. Stevens, B. Stevenson, T. Stolarczyk, G. Stratta, U. Straumann, J. Striskovic, M. Strzys, R. Stuik, M. Suchenek, Y. Sunada, Tiina Suomijarvi, T. Suric, H. Suzuki, P. Swierk, T. Szepieniec, K. Tachihara, G. Tagliaferri, H. Tajima, N. Tajima, D. Tak, H. Takahashi, M. Takahashi, J. Takata, R. Takeishi, T. Tam, M. Tanaka, T. Tanaka, S. Tanaka, M. Tavani, F. Tavecchio, T. Tavernier, A. Russ Taylor, L.A. Tejedor, P. Temnikov, K. Terauchi, J.C. Terrazas, R. Terrier, T. Terzic, M. Teshima, D. Thibaut, F. Thocquenne, W. Tian, L. Tibaldo, A. Tiengo, M. Tluczykont, C.J. Todero Peixoto, K. Toma, L. Tomankova, J. Tomastik, M. Tornikoski, D.F. Torres, E. Torresi, G. Tosti, L. Tosti, N. Tothill, F. Toussenel, G. Tovmassian, C. Trichard, M. Trifoglio, A. Trois, S. Truzzi, A. Tsiahina, B. Turk, A. Tutone, Y. Uchiyama, P. Utayarat, L. Vaclavek, M. Vacula, V. Vagelli, F. Vagnetti, J.A. Valdivia, M. Valentino, A. Valio, B. Vallage, P. Vallania Quispe, A.M. van den Berg, W. van Driel, C. van Eldik, C. van Rensburg, Brian van Soelen, J. Vandenbroucke, G. Vasileiadis, V. Vassiliev, M. Vazquez Acosta, M. Vecchi, A. Vega, J. Veh, P. Veitch, C. Venter, S. Ventura, S. Vercellone, V. Verguilov, G. Verna, S. Vernetto, V. Verzi, G.P. Vettolani, C. Veyssiere, I. Viale, A. Viana, N. Viaux, J. Vignatti, C.F. Vigorito, J. Villanueva, V. Vitale, V. Vittorini, V. Vodeb, N. Vogel, V. Voisin, S. Vorobiov, M. Vrastil, T. Vuillaume, S.J. Wagner, P. Wagner, K. Wakazono, S.P. Wakely, M. Ward, D. Warren, J. Watson, M. Wechakama, P. Wegner, A. Weinstein, C. Weniger, F. Werner, H. Wetteskind, M. L. White, A. Wierzcholska, S. Wiesand, R. Wijers, M. Wilkinson, M. Will, J. Williams, T. J. Williamson, A. Wolter, Y.W. Wong, M. Wood, T. Yamamoto, H. Yamamoto, Y. Yamane, R. Yamazaki, S. Yanagita, L. Yang, S. Yoo, T. Yoshida, T. Yoshikoshi, P. Yu, A. Yusafzai, Michael Zacharias, B. Zaldivar, L. Zampieri, R. Zanin, R. Zanmar Sanchez, D. Zaric, M. Zavrtanik, D. Zavrtanik, Andrzej Zdziarski, A. Zech, H. Zechlin, A. Zenin, A. Zerwekh, K. Ziętara, A. Zink, J. Ziolkowski, M. Zivec, A. Zmija, Współautorami artykułu są członkowie CTA Observatory, CTA Consortium i LST Collaboration w liczbie 1139, Astronomy, Research unit Nuclear & Hadron Physics, and Research unit Astroparticle Physics
Subjects: Physics, Observatory, Gamma ray, Astronomy
Abstract: Very-high Energy (VHE) gamma-ray astroparticle physics is a relatively young field, and observations over the past decade have surprisingly revealed almost two hundred VHE emitters which appear to act as cosmic particle accelerators. These sources are an important component of the Universe, influencing the evolution of stars and galaxies. At the same time, they also act as a probe of physics in the most extreme environments known - such as in supernova explosions, and around or after the merging of black holes and neutron stars. However, the existing experiments have provided exciting glimpses, but often falling short of supplying the full answer. A deeper understanding of the TeV sky requires a significant improvement in sensitivity at TeV energies, a wider energy coverage from tens of GeV to hundreds of TeV and a much better angular and energy resolution with respect to the currently running facilities. The next generation gamma-ray observatory, the Cherenkov Telescope Array Observatory (CTAO), is the answer to this need. In this talk I will present this upcoming observatory from its design to the construction, and its potential science exploitation. CTAO will allow the entire astronomical community to explore a new discovery space that will likely lead to paradigm-changing breakthroughs. In particular, CTA has an unprecedented sensitivity to short (sub-minute) timescale phenomena, placing it as a key instrument in the future of multi-messenger and multi-wavelength time domain astronomy. I will conclude the talk presenting the first scientific results obtained by the LST-1, the prototype of one CTAO telescope type - the Large-Sized Telescope, that is currently under commission., PoS: Proceedings of Science, 395, ISSN:1824-8039, Proceedings of 37th International Cosmic Ray Conference (ICRC2021)
Published: 2022

12. Facies Variations of Upper Jurassic Source Rocks in the Northern North Sea

Author: G. Skarstein, S. Ohm, A. Cedeño, and A. Escalona
Published: 2022

13. The H.E.S.S. Gravitational Wave Rapid Follow-up Program during O2 and O3

Author: Fabian Schüssler, Francois Brun, Patrick Reichherzer, S. Ohm, Halim Ashkar, Monica Seglar Arroyo, Sylvia Zhu, Ruslan Konno, Heike Prokoph, M. Füßling, Sylvia J. Zhu, Clemens Hoischen, Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Laboratoire d'Annecy de Physique des Particules (LAPP), and Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)
Subjects: data analysis method, neutron star: binary, media_common.quotation_subject, Astrophysics::High Energy Astrophysical Phenomena, VHE [gamma ray], FOS: Physical sciences, burst [gamma ray], absorption: effect, Field of view, binary [neutron star], effect [absorption], gamma ray: burst, 01 natural sciences, emission [gravitational radiation], binary: coalescence, HESS, 0103 physical sciences, Astronomical interferometer, binary [black hole], ddc:530, High Energy Stereoscopic System, LIGO, Instrumentation and Methods for Astrophysics (astro-ph.IM), 010303 astronomy & astrophysics, media_common, High Energy Astrophysical Phenomena (astro-ph.HE), Physics, 010308 nuclear & particles physics, Gravitational wave, Astronomy, Galaxy, Afterglow, Cherenkov counter, VIRGO, gamma ray: VHE, black hole: binary, Sky, gravitational radiation: emission, galaxy, gravitational radiation: localization, coalescence [binary], Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - High Energy Astrophysical Phenomena, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], localization [gravitational radiation]
Abstract: 37th International Cosmic Ray Conference, ICRC 2021, Berlin, online, Germany, 12 Jul 2021 - 23 Jul 2021; Proceedings of Science / International School for Advanced Studies (ICRC2021), 936 (2021). doi:10.22323/1.395.0936, Since 2015, the direct detection of Gravitational Waves (GWs) became possible with ground-based interferometers like LIGO and Virgo. GWs became the center of attention of the astronomical community and electromagnetic observatories took a particular interest in follow-up observations of such events. The main setback of these observations is the poor localization of GW events. In fact, GW localization uncertainties can span tens to hundreds of deg$^2$ the sky even with the advanced configurations of current GW interferometers. In this contribution, we present five follow-up strategies developed for the High Energy Stereoscopic System (H.E.S.S.) and assess their performances. We show how a 2D and 3D galaxy targeted search approach exploiting the integral probability inside the instruments field of view are best suited for medium field of view instruments like H.E.S.S. We also develop an automatic response scheme within the H.E.S.S. Transient Follow-up system that is optimized for fast response and is capable of responding promptly to all kind of GW alerts. GW events are filtered by the developed scheme and prompt and afterglow observations are automatically scheduled. The H.E.S.S. response latency to prompt alerts is measured to be less than 1 minute. With this continually optimized GW response scheme, H.E.S.S. scheduled several GW follow-up observations during the second and third LIGO/Virgo observation runs., Published by SISSA, Trieste
Published: 2021

14. Making cosmic particle accelerators visible and audible

Author: M. Füßling, Till Mundzeck, S. Ohm, Konrad Rappaport, Carsten Nicolai, Sylvia J. Zhu, R. D. Parsons, and Andrew M. Taylor
Subjects: Physics, High Energy Astrophysical Phenomena (astro-ph.HE), COSMIC cancer database, law, Astronomy, FOS: Physical sciences, Particle accelerator, ddc:530, Astrophysics - High Energy Astrophysical Phenomena, law.invention
Abstract: 37th International Cosmic Ray Conference, ICRC 2021, Berlin, online, Germany, 12 Jul 2021 - 23 Jul 2021; Proceedings of Science / International School for Advanced Studies (ICRC2021), 1391 (2021). doi:10.22323/1.395.1391, In a collaboration between astroparticle physicists, animation artists from the award-winning Science Communication Lab, and musician Carsten Nicolai (a.k.a. Alva Noto), two cosmic particle accelerators have been brought to life: the massive binary star Eta Carinae, and the exploding star, which resulted in the gamma-ray burst GRB190829A. For Eta Carinae, the computer-generated images are close to reality because the measured orbital, stellar, and wind parameters were used for this purpose. Particle acceleration in the jet of GRB190829A has also been animated at a level of detail not seen before. The internationally acclaimed multimedia artist Carsten Nicolai, who uses the pseudonym Alva Noto for his musical works, exclusively composed the sound for the animations. The multimedia projects aim at making the discoveries more accessible to the general public, and to mediate scientific results and their reference to reality from an artistic point of view., Published by SISSA, Trieste
Published: 2021

15. The upgraded Data Acquisition System of the H.E.S.S. telescope array

Author: Matthias Fuessling, Tim Holch, Fabian Krack, Thomas Murach, Klemens Mosshammer, Sylvia J. Zhu, R. Lindemann, Mathieu de Naurois, S. Ohm, Laboratoire Leprince-Ringuet (LLR), and Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)
Subjects: Computer science, Physics::Instrumentation and Detectors, data acquisition, Astrophysics::High Energy Astrophysical Phenomena, VHE [gamma ray], FOS: Physical sciences, GeV, programming, law.invention, Telescope, Data acquisition, law, HESS, Cherenkov [radiation], hardware, ddc:530, [PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det], cluster, Instrumentation and Methods for Astrophysics (astro-ph.IM), Remote sensing, High Energy Astrophysical Phenomena (astro-ph.HE), energy: high, Astrophysics::Instrumentation and Methods for Astrophysics, imaging, radiation: Cherenkov, Cherenkov counter, gamma ray: VHE, atmosphere, high [energy], interface, upgrade, Astrophysics::Earth and Planetary Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - High Energy Astrophysical Phenomena, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], performance
Abstract: 37th International Cosmic Ray Conference, ICRC 2021, Berlin, Germany, 15 Jul 2021 - 22 Jul 2021; Proceedings of Science / International School for Advanced Studies (ICRC2021), 759 (2021). doi:10.22323/1.395.0759, The High Energy Stereoscopic System (H.E.S.S.) is an array of five Imaging Atmospheric Cherenkov Telescopes located in the Khomas Highland of Namibia. H.E.S.S. observes gamma rays above tens of GeV by detecting the Cherenkov light that is produced when Very High Energy gamma rays interact with the Earth��s atmosphere. The H.E.S.S. Data Acquisition System (DAQ) coordinates the nightly telescope operations, ensuring that the various components communicate properly and behave as intended. It also provides the interface between the telescopes and the people on shift who guide the operations. The DAQ comprises both the hardware and software, and since the beginning of H.E.S.S., both elements have been continuously adapted to improve the data-taking capabilities of the array and push the limits of what H.E.S.S. is capable of. Most recently, this includes the upgrade of the entire computing cluster hosting the DAQ software, and the accommodation of a new camera on the large 28m H.E.S.S. telescope. We discuss the performance of the upgraded DAQ and the lessons learned from these activities., Published by SISSA, Trieste
Published: 2021

16. Kr-Plasma Process for Conductance Control of MFSFET With FeND-HfO₂ Gate Insulator

Author: S. Ohmi, M. Tanuma, and J.W. Shin
Subjects: Hafnium oxide, nondoped, ferroelectrics, MFSFET, Kr-plasma, threshold voltage, Electrical engineering. Electronics. Nuclear engineering, TK1-9971
Abstract: In this work, we have investigated the conductance control of the metal-ferroelectrics-Si field-effect transistor (MFSFET) utilizing 5 nm thick ferroelectric nondoped $\rm HfO_{2}$ (FeND-HfO2) gate insulator. The Kr-plasma process is effective to decrease the plasma damage compared to the Ar-plasma process during the in-situ deposition of FeND-HfO2 and Pt gate electrode by RF-magnetron sputtering. The precise control such as less than 20 mV was realized which led to the conductance control for 10 states from 0 to $0.6~\mu $ S/ $\mu $ m both for potentiation and depression operations with the input pulses of $\mathbf {\pm 3}$ V/100 ns.
Published: 2024
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17. Neutron capture reaction cross-section of 79Se through the 79Se(d,p) reaction in inverse kinematics

Author: N. Imai, M. Dozono, S. Michimasa, T. Sumikama, S. Ota, S. Hayakawa, J.W. Hwang, K. Iribe, C. Iwamoto, S. Kawase, K. Kawata, N. Kitamura, S. Masuoka, K. Nakano, P. Schrock, D. Suzuki, R. Tsunoda, K. Wimmer, D.S. Ahn, O. Beliuskina, N. Chiga, N. Fukuda, E. Ideguchi, K. Kusaka, H. Miki, H. Miyatake, D. Nagae, S. Ohmika, M. Ohtake, H.J. Ong, H. Otsu, H. Sakurai, H. Shimizu, Y. Shimizu, X. Sun, H. Suzuki, M. Takaki, H. Takeda, S. Takeuchi, T. Teranishi, Y. Watanabe, Y.X. Watanabe, K. Yako, H. Yamada, H. Yamaguchi, L. Yang, R. Yanagihara, Y. Yanagisawa, K. Yoshida, and S. Shimoura
Subjects: Physics, QC1-999
Abstract: γ emission probabilities from unbound states in 78,80Se, populated by a neutron-transfer reaction (d,p) on 77,79Se nuclei in inverse kinematics, were measured by directly detecting reaction residues. Assuming the spin distribution at the respective excitation energy of the unbound state, the cross-sections of the 79Se(n,γ)80Se reaction were evaluated using the γ emission probabilities. The surrogate-ratio method with the experimental γ emission probabilities of 78,80Se was also employed to deduce the cross-sections of 79Se(n,γ) reaction by incorporating the theoretical evaluations of the neutron-capture reaction on the isomeric state in 77Se. Our two cross-sections are in good agreement with existing nuclear data compilations for the neutron-capture reaction on 79Se. The presented method contributes to the body of existing knowledge by providing approaches for determining the neutron capture cross-sections of radioactive nuclei at various neutron energies.
Published: 2024
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18. Multiwavelength observation of MAXI J1820+070 with MAGIC, VERITAS and H.E.S.S

Author: E. Molina, M. de Naurois, Oscar Blanch, S. Ohm, N. Park, D. Malyshev, Gernot Maier, Alison Mitchell, M. Lopez, E. de Oña Wilhelmi, Roberta Zanin, John Hoang, Jean-Pierre Ernenwein, Juan Cortina, Marc Ribó, Laboratoire Leprince-Ringuet (LLR), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Centre de Physique des Particules de Marseille (CPPM), Aix Marseille Université (AMU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), MAGIC, VERITAS, H.E.S.S., Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Aix Marseille Université (AMU), and MAGIC, VERITAS
Subjects: Physics, High Energy Astrophysical Phenomena (astro-ph.HE), High energy, media_common.quotation_subject, Magic (programming), FOS: Physical sciences, Astrophysics, sensitivity, MAGIC, X-ray, gamma ray: emission, gamma ray: VHE, Sky, pixel, HESS, optical, black hole, gamma ray: detector, VERITAS, quasar, Astrophysics - High Energy Astrophysical Phenomena, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], media_common
Abstract: 36th International Cosmic Ray Conference (ICRC2019), Madison, USA, 24 Jul 2019 - 1 Aug 2019, MAXI J1820+070 is a new low-mass microquasar hosting a black hole recently discovered in X-rays by the MAXI instrument. It is the counterpart of ASASSN-18ey, discovered in optical a few days before by ASAS-SN. This source underwent a major outburst in 2018, during which it completed the typical 'q-shaped' path in the hardness-intensity diagram. MAGIC, VERITAS and H.E.S.S. gamma-ray telescopes observed the sky position of MAXI J1820+070 for a total of more than 90 hours in 2018. In addition, some observations were carried out using MAGIC Central Pixel - a dedicated central pixel capable of detecting fast optical signals (10 kHz sampling rate, peak sensitivity in the U-band). This contribution presents the methods used to search for transient optical and very high energy gamma-ray emission from MAXI J1820+070, as well as the latest results in these energy ranges.
Published: 2019
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19. A very-high-energy component deep in the $\gamma$-ray burst afterglow

Author: H. Abdalla, R. Adam, F. Aharonian, F. Ait Benkhali, E. O. Angüner, M. Arakawa, C. Arcaro, C. Armand, H. Ashkar, M. Backes, V. Barbosa Martins, M. Barnard, Y. Becherini, D. Berge, K. Bernlöhr, E. Bissaldi, R. Blackwell, M. Böttcher, C. Boisson, J. Bolmont, S. Bonnefoy, J. Bregeon, M. Breuhaus, F. Brun, P. Brun, M. Bryan, M. Büchele, T. Bulik, T. Bylund, M. Capasso, S. Caroff, A. Carosi, S. Casanova, M. Cerruti, T. Chand, S. Chandra, A. Chen, S. Colafrancesco, M. Curyło, I. D. Davids, C. Deil, J. Devin, P. deWilt, L. Dirson, A. Djannati-Ataï, A. Dmytriiev, A. Donath, V. Doroshenko, J. Dyks, K. Egberts, G. Emery, J.-P. Ernenwein, S. Eschbach, K. Feijen, S. Fegan, A. Fiasson, G. Fontaine, S. Funk, M. Füßling, S. Gabici, Y. A. Gallant, F. Gaté, G. Giavitto, L. Giunti, D. Glawion, J. F. Glicenstein, D. Gottschall, M.-H. Grondin, J. Hahn, M. Haupt, G. Heinzelmann, G. Henri, G. Hermann, J. A. Hinton, W. Hofmann, C. Hoischen, T. L. Holch, M. Holler, D. Horns, D. Huber, H. Iwasaki, M. Jamrozy, D. Jankowsky, F. Jankowsky, A. Jardin-Blicq, I. Jung-Richardt, M. A. Kastendieck, K. Katarzyński, M. Katsuragawa, U. Katz, D. Khangulyan, B. Khélifi, J. King, S. Klepser, W. Kluźniak, Nu. Komin, K. Kosack, D. Kostunin, M. Kreter, G. Lamanna, A. Lemière, M. Lemoine-Goumard, J.-P. Lenain, E. Leser, C. Levy, T. Lohse, I. Lypova, J. Mackey, J. Majumdar, D. Malyshev, V. Marandon, A. Marcowith, A. Mares, C. Mariaud, G. Martí-Devesa, R. Marx, G. Maurin, P. J. Meintjes, A. M. W. Mitchell, R. Moderski, M. Mohamed, L. Mohrmann, C. Moore, E. Moulin, J. Muller, T. Murach, S. Nakashima, M. de Naurois, H. Ndiyavala, F. Niederwanger, J. Niemiec, L. Oakes, P. O’Brien, H. Odaka, S. Ohm, E. de Ona Wilhelmi, M. Ostrowski, I. Oya, M. Panter, R. D. Parsons, C. Perennes, P.-O. Petrucci, B. Peyaud, Q. Piel, S. Pita, V. Poireau, A. Priyana Noel, D. A. Prokhorov, H. Prokoph, G. Pühlhofer, M. Punch, A. Quirrenbach, S. Raab, R. Rauth, A. Reimer, O. Reimer, Q. Remy, M. Renaud, F. Rieger, L. Rinchiuso, C. Romoli, G. Rowell, B. Rudak, E. Ruiz-Velasco, V. Sahakian, S. Sailer, S. Saito, D. A. Sanchez, A. Santangelo, M. Sasaki, R. Schlickeiser, F. Schüssler, A. Schulz, H. M. Schutte, U. Schwanke, S. Schwemmer, M. Seglar-Arroyo, M. Senniappan, A. S. Seyffert, N. Shafi, K. Shiningayamwe, R. Simoni, A. Sinha, H. Sol, A. Specovius, M. Spir-Jacob, Ł. Stawarz, R. Steenkamp, C. Stegmann, C. Steppa, T. Takahashi, T. Tavernier, A. M. Taylor, R. Terrier, D. Tiziani, M. Tluczykont, C. Trichard, M. Tsirou, N. Tsuji, R. Tuffs, Y. Uchiyama, D. J. van der Walt, C. van Eldik, C. van Rensburg, B. van Soelen, G. Vasileiadis, J. Veh, C. Venter, P. Vincent, J. Vink, H. J. Völk, T. Vuillaume, Z. Wadiasingh, S. J. Wagner, R. White, A. Wierzcholska, R. Yang, H. Yoneda, M. Zacharias, R. Zanin, A. A. Zdziarski, A. Zech, A. Ziegler, J. Zorn, N. Żywucka, F. de Palma, M. Axelsson, O. J. Roberts, Laboratoire Leprince-Ringuet (LLR), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Centre de Physique des Particules de Marseille (CPPM), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Aix Marseille Université (AMU), Laboratoire d'Annecy de Physique des Particules (LAPP/Laboratoire d'Annecy-le-Vieux de Physique des Particules), Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Laboratoire Univers et Théories (LUTH (UMR_8102)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Univers et Particules de Montpellier (LUPM), Université de Montpellier (UM)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE (UMR_7585)), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), AstroParticule et Cosmologie (APC (UMR_7164)), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Aix Marseille Université (AMU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Annecy de Physique des Particules (LAPP), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Montpellier 2 - Sciences et Techniques (UM2), Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Centre National d'Études Spatiales [Toulouse] (CNES)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA), Abdalla, H., Adam, R., Aharonian, F., Ait Benkhali, F., Anguner, E. O., Arakawa, M., Arcaro, C., Armand, C., Ashkar, H., Backes, M., Barbosa Martins, V., Barnard, M., Becherini, Y., Berge, D., Bernlohr, K., Bissaldi, E., Blackwell, R., Bottcher, M., Boisson, C., Bolmont, J., Bonnefoy, S., Bregeon, J., Breuhaus, M., Brun, F., Brun, P., Bryan, M., Buchele, M., Bulik, T., Bylund, T., Capasso, M., Caroff, S., Carosi, A., Casanova, S., Cerruti, M., Chand, T., Chandra, S., Chen, A., Colafrancesco, S., Curylo, M., Davids, I. D., Deil, C., Devin, J., Dewilt, P., Dirson, L., Djannati-Atai, A., Dmytriiev, A., Donath, A., Doroshenko, V., Dyks, J., Egberts, K., Emery, G., Ernenwein, J. -P., Eschbach, S., Feijen, K., Fegan, S., Fiasson, A., Fontaine, G., Funk, S., Fussling, M., Gabici, S., Gallant, Y. A., Gate, F., Giavitto, G., Giunti, L., Glawion, D., Glicenstein, J. F., Gottschall, D., Grondin, M. -H., Hahn, J., Haupt, M., Heinzelmann, G., Henri, G., Hermann, G., Hinton, J. A., Hofmann, W., Hoischen, C., Holch, T. L., Holler, M., Horns, D., Huber, D., Iwasaki, H., Jamrozy, M., Jankowsky, D., Jankowsky, F., Jardin-Blicq, A., Jung-Richardt, I., Kastendieck, M. A., Katarzynski, K., Katsuragawa, M., Katz, U., Khangulyan, D., Khelifi, B., King, J., Klepser, S., Kluzniak, W., Komin, N., Kosack, K., Kostunin, D., Kreter, M., Lamanna, G., Lemiere, A., Lemoine-Goumard, M., Lenain, J. -P., Leser, E., Levy, C., Lohse, T., Lypova, I., Mackey, J., Majumdar, J., Malyshev, D., Marandon, V., Marcowith, A., Mares, A., Mariaud, C., Marti-Devesa, G., Marx, R., Maurin, G., Meintjes, P. J., Mitchell, A. M. W., Moderski, R., Mohamed, M., Mohrmann, L., Moore, C., Moulin, E., Muller, J., Murach, T., Nakashima, S., de Naurois, M., Ndiyavala, H., Niederwanger, F., Niemiec, J., Oakes, L., O'Brien, P., Odaka, H., Ohm, S., de Ona Wilhelmi, E., Ostrowski, M., Oya, I., Panter, M., Parsons, R. D., Perennes, C., Petrucci, P. -O., Peyaud, B., Piel, Q., Pita, S., Poireau, V., Priyana Noel, A., Prokhorov, D. A., Prokoph, H., Puhlhofer, G., Punch, M., Quirrenbach, A., Raab, S., Rauth, R., Reimer, A., Reimer, O., Remy, Q., Renaud, M., Rieger, F., Rinchiuso, L., Romoli, C., Rowell, G., Rudak, B., Ruiz-Velasco, E., Sahakian, V., Sailer, S., Saito, S., Sanchez, D. A., Santangelo, A., Sasaki, M., Schlickeiser, R., Schussler, F., Schulz, A., Schutte, H. M., Schwanke, U., Schwemmer, S., Seglar-Arroyo, M., Senniappan, M., Seyffert, A. S., Shafi, N., Shiningayamwe, K., Simoni, R., Sinha, A., Sol, H., Specovius, A., Spir-Jacob, M., Stawarz, L., Steenkamp, R., Stegmann, C., Steppa, C., Takahashi, T., Tavernier, T., Taylor, A. M., Terrier, R., Tiziani, D., Tluczykont, M., Trichard, C., Tsirou, M., Tsuji, N., Tuffs, R., Uchiyama, Y., van der Walt, D. J., van Eldik, C., van Rensburg, C., van Soelen, B., Vasileiadis, G., Veh, J., Venter, C., Vincent, P., Vink, J., Volk, H. J., Vuillaume, T., Wadiasingh, Z., Wagner, S. J., White, R., Wierzcholska, A., Yang, R., Yoneda, H., Zacharias, M., Zanin, R., Zdziarski, A. A., Zech, A., Ziegler, A., Zorn, J., Zywucka, N., de Palma, F., Axelsson, M., Roberts, O. J., Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS), Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), 26598973 - Abdalla, Hassan, 30588766 - Arcaro, Cornelia, 28644743 - Backes, Michael, 20574266 - Barnard, Monica, 24420530 - Böttcher, Markus, 30366755 - Chand, Tej B., 31125417 - Chandra, Sunil, 26403366 - Ndiyavala, Hambeleleni, 22799133 - Schutte, Hester M., 20126999 - Seyffert, Albertus Stefanus, 10060499 - Van der Walt, Diederick Johannes, 21106266 - Van Rensburg, Carlo, 12006653 - Venter, Christo, 26594080 - Wadiasingh, Zorawar, 29092086 - Zacharias, Michael, 34208968 - Zywucka-Hejzner, Natalia, 33379009 - Kreter, Michael, Faculty of Science, and High Energy Astrophys. & Astropart. Phys (API, FNWI)
Subjects: electron, Brightness, Photon, Astrophysics::High Energy Astrophysical Phenomena, brightness, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Radiation, gamma ray: burst, 7. Clean energy, 01 natural sciences, VHE, Transient astrophysical phenomena, 0103 physical sciences, synchrotron, ddc:530, 010303 astronomy & astrophysics, X-ray: flux, Astrophysics::Galaxy Astrophysics, Physics, High Energy Astrophysical Phenomena (astro-ph.HE), Range (particle radiation), Multidisciplinary, 010308 nuclear & particles physics, particle: energy, photon, Gamma ray, Time-domain astronomy, Institut für Physik und Astronomie, Afterglow, High-energy astrophysics, Automatic Keywords, gamma ray: UHE, Orders of magnitude (time), 13. Climate action, Gamma-ray burst, Particle astrophysics, Astrophysics - High Energy Astrophysical Phenomena, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract: Gamma-ray bursts (GRBs) are brief flashes of gamma rays, considered to be the most energetic explosive phenomena in the Universe. The emission from GRBs comprises a short (typically tens of seconds) and bright prompt emission, followed by a much longer afterglow phase. During the afterglow phase, the shocked outflow -- produced by the interaction between the ejected matter and the circumburst medium -- slows down, and a gradual decrease in brightness is observed. GRBs typically emit most of their energy via gamma-rays with energies in the kiloelectronvolt-to-megaelectronvolt range, but a few photons with energies of tens of gigaelectronvolts have been detected by space-based instruments. However, the origins of such high-energy (above one gigaelectronvolt) photons and the presence of very-high-energy (more than 100 gigaelectronvolts) emission have remained elussive. Here we report observations of very-high-energy emission in the bright GRB 180720B deep in the GRB afterglow -ten hours after the end of the prompt emission phase, when the X-ray flux had already decayed by four orders of magnitude. Two possible explanations exist for the observed radiation: inverse Compton emission and synchrotron emission of ultrarelativistic electrons. Our observations show that the energy fluxes in the X-ray and gamma-ray range and their photon indices remain comparable to each other throughout the afterglow. This discovery places distinct constraints on the GRB environment for both emission mechanisms, with the inverse Compton explanation alleviating the particle energy requirements for the emission observed at late times. The late timing of this detection has consequences for the future observations of GRBs at the highest energies., Comment: Preprint version of Nature paper. Contacts: E.Ruiz-Velasco, F. Aharonian, E.Bissaldi, C.Hoischen, R.D Parsons, Q.Piel, A.Taylor, D.Khangulyan
Published: 2019

20. A NECTAr-based upgrade for the Cherenkov cameras of the H.E.S.S. 12-meter telescopes

Author: H. Leich, Thomas Murach, T. Schwab, Marko Kossatz, P. Nayman, Albert Jahnke, Francois Brun, P. Vincent, J.-P. Lenain, Jim Hinton, Christian Stegmann, A. Balzer, J. Bolmont, J. F. Glicenstein, P. Manigot, M. Füßling, Eric Delagnes, Michael Backes, Gianluca Giavitto, Marek Penno, T. Chaminade, F. Toussenel, Terry Ashton, M. de Naurois, David Salek, E. Moulin, D. Berge, Gerard Fontaine, J.-P. Tavernet, Kleopas Shiningayamwe, S. Ohm, V. Lefranc, A. Kretzschmann, J. Thornhill, H. Lüdecke, V. Marandon, Markus Schade, Stefan Klepser, B. Giebels, Iryna Lypova, D. Ross, Tobias Gräber, S. Bonnefoy, Constantin Steppa, Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE (UMR_7585)), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Laboratoire Leprince-Ringuet (LLR), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), 28644743 - Backes, Michael, Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Centre National de la Recherche Scientifique (CNRS), and Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Ethernet, data acquisition, atmosphere [Cherenkov counter], computer: communications, High-energy instrumentation upgrade, 01 natural sciences, design [detector], Cherenkov camera, Data acquisition, Software, HESS, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], High Energy Stereoscopic System, 010303 astronomy & astrophysics, ComputingMilieux_MISCELLANEOUS, FPGA, NECTAr, Physics, Upgrade, H.E.S.S, ddc:540, design [electronics], mechanical engineering, upgrade, Astrophysics - Instrumentation and Methods for Astrophysics, performance, Computer hardware, Photomultiplier, ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION, FOS: Physical sciences, Cherenkov counter: atmosphere, electrical engineering, programming, 0103 physical sciences, communications [computer], [PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det], Electronics, Instrumentation and Methods for Astrophysics (astro-ph.IM), detector: design, Cherenkov radiation, Gamma-ray astronomy, 010308 nuclear & particles physics, business.industry, Astronomy and Astrophysics, PMT Cameras, trigger, electronics: readout, HESS - Abteilung Hinton, photon: detector, readout [electronics], business, detector [photon], electronics: design
Abstract: The High Energy Stereoscopic System (H.E.S.S.) is one of the three arrays of imaging atmospheric Cherenkov telescopes (IACTs) currently in operation. It is composed of four 12-meter telescopes and a 28-meter one, and is sensitive to gamma rays in the energy range ~30 GeV - 100 TeV. The cameras of the 12-m telescopes recently underwent a substantial upgrade, with the goal of improving their performance and robustness. The upgrade involved replacing all camera components except for the photomultiplier tubes (PMTs). This meant developing new hardware for the trigger, readout, power, cooling and mechanical systems, and new software for camera control and data acquisition. Several novel technologies were employed in the cameras: the readout is built around the new NECTAr digitizer chip, developed for the next generation of IACTs; the camera electronics is fully controlled and read out via Ethernet using a combination of FPGA and embedded ARM computers; the software uses modern libraries such as Apache Thrift, ZMQ and Protocol buffers. This work describes in detail the design and the performance of the upgraded cameras., Comment: 35 pages, 14 figures, accepted for publication in "Astroparticle physics"
Published: 2020

21. First Results of Eta Carinae Observations with H.E.S.S. II

Author: A. Reimer, Jim Hinton, Mathieu de Naurois, M. Füßling, Olaf Reimer, Stefan Klepser, Kathrin Egberts, Eva Leser, S. Ohm, Pol Bordas, Laboratoire Leprince-Ringuet (LLR), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), and H.E.S.S.
Subjects: Astrophysics::High Energy Astrophysical Phenomena, binary, Astrophysics, gamma ray: energy spectrum, 01 natural sciences, Upper and lower bounds, GLAST, law.invention, X-ray, Telescope, energy: threshold, law, HESS, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, High Energy Stereoscopic System, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Physics, energy: high, Range (particle radiation), 010308 nuclear & particles physics, Gamma ray, sensitivity, spectral, High Energy Physics::Experiment, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], upper limit
Abstract: International audience; Eta Carinae is a colliding-wind binary that shows non-thermal emission from hard X-rays to high-energy gamma rays. The gamma-ray spectrum exhibits two spectral components, where the high-energy component extends up to 300 GeV.Previous observations of Eta Carinae with the High Energy Stereoscopic System (H.E.S.S.) resulted in upper limits. With the addition of the large 28-m central telescope to the H.E.S.S. array in 2012 the lower bound on the energy range has significantly been reduced. This lowers the energy threshold of the analysis compared to the published results due to the improved instruments’ sensitivity at energies below 400 GeV. Eta Carinae has been regularly observed in the following years with H.E.S.S. II.Here we report on the first results of Eta Carinae observations, which also cover the periastron passage in 2014 - the time of maximum gamma-ray emission seen in GeV gamma-rays with Ferm-LAT.
Published: 2017

22. Feasibility study on a thermoset polymer-coated emulsified warm-mix asphalt mixture

Author: B. S. Ohm, Imad L. Al-Qadi, K. S. Park, and Pyeong Jun Yoo
Subjects: Materials science, Asphalt, Thermosetting polymer, Composite material
Published: 2017

23. Observations of Bow Shocks of Runaway Stars with H.E.S.S

Author: S. Ohm, A. Schulz, S. Klepser, and M. Haupt
Subjects: High Energy Astrophysical Phenomena (astro-ph.HE), Physics, Astrophysics::High Energy Astrophysical Phenomena, Theoretical models, FOS: Physical sciences, Flux, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Interstellar medium, Stars, Bow shock (aerodynamics), Astrophysics - High Energy Astrophysical Phenomena, Astrophysics::Galaxy Astrophysics, Systematic search
Abstract: Runaway stars form bow shocks by sweeping up interstellar matter in their direction of motion. Theoretical models predict a spectrally wide non-thermal component reaching up to gamma-ray energies at a flux level detectable with current instruments. They were motivated by a detection of non-thermal radio emission from the bow shock of BD$+43^\circ3654$ and a possible detection of non-thermal X-rays from AE Aurigae. A search in the high-energy regime using data from \textit{Fermi}-LAT resulted in flux upper limits for 27 candidates listed in the first E-BOSS catalogue. We perform the first systematic search for TeV emission from bow shocks of runaway stars. Using all available archival H.E.S.S. I data we search for very-high-energy gamma-ray emission at the positions of bow shock candidates listed in the second E-BOSS catalogue. This catalogue comprises 73 bow shock candidates, 32 of which have been observed with the H.E.S.S. telescopes. None of the observed bow shock candidates shows significant emission in the H.E.S.S. energy range. The resulting upper limits are used to constrain current models for non-thermal emission from these objects., 5 pages, 4 figures, Contribution to the 6th International Symposium on High Energy Gamma-Ray Astronomy (Gamma2016), July 11-15, 2016, Heidelberg, Germany. To be published in the AIP Conference Proceedings
Published: 2016

24. The H.E.S.S. multi-messenger program: Searches for TeV gamma-ray emission associated with high-energy neutrinos

Author: M. Lorentz, D. Parsons, F. Schüssler, Michael Backes, Clemens Hoischen, Francois Brun, S. Ohm, A. Balzer, M. Füssling, Iryna Lypova, A. Reimer, J.-P. Lenain, Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE (UMR_7585)), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), H.E.S.S., and Université Sciences et Technologies - Bordeaux 1 (UB)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)
Subjects: accelerator, media_common.quotation_subject, Astrophysics::High Energy Astrophysical Phenomena, Cosmic ray, 01 natural sciences, Coincidence, hadronic, IceCube, HESS, 0103 physical sciences, Angular resolution, 010303 astronomy & astrophysics, Cherenkov radiation, media_common, Physics, ANTARES, 010308 nuclear & particles physics, Gamma ray, Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy, imaging, flux, gamma ray: emission, neutrino: detector, Cherenkov counter, Neutrino detector, angular resolution, 13. Climate action, Sky, cosmic radiation, High Energy Physics::Experiment, Neutrino, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract: International audience; The observation of an astrophysical flux of high-energy neutrinos by the IceCube collaboration opened the path to multi-messenger studies searching for the origin of high-energy cosmic rays since the detected neutrinos possibly originate in hadronic interactions near cosmic-ray accelerators. Although the neutrino sky map shows no indication of localized sources so far, the angular resolution of individual track-like events is sufficiently small to search for associated gamma-ray emission with Imaging Atmospheric Cherenkov Telescopes like H.E.S.S.Here we present the H.E.S.S. multi-messenger program to follow up on high-energy neutrino events. We show first results from searches for high-energy gamma-ray emission in spatial coincidence with neutrino events detected by the IceCube and ANTARES neutrino telescopes and discuss recent extensions towards a fully integrated real-time alert system between neutrino telescopes and the H.E.S.S. gamma-ray experiment.
Published: 2016

25. Simultaneous HESS and Chandra observations of Sagitarius A$^{\star}$ during an X-ray flare

Author: F. Aharonian, A. G. Akhperjanian, U. Barres de Almeida, A. R. Bazer-Bachi, Y. Becherini, B. Behera, W. Benbow, K. Bernlöhr, C. Boisson, A. Bochow, V. Borrel, I. Braun, E. Brion, J. Brucker, P. Brun, R. Bühler, T. Bulik, I. Büsching, T. Boutelier, S. Carrigan, P. M. Chadwick, A. Charbonnier, R. C. G. Chaves, A. Cheesebrough, L.-M. Chounet, A. C. Clapson, G. Coignet, M. Dalton, B. Degrange, C. Deil, H. J. Dickinson, A. Djannati-Ataï, W. Domainko, L. O'C. Drury, F. Dubois, G. Dubus, J. Dyks, M. Dyrda, K. Egberts, D. Emmanoulopoulos, P. Espigat, C. Farnier, F. Feinstein, A. Fiasson, A. Förster, G. Fontaine, M. Füßling, S. Gabici, Y. A. Gallant, L. Gérard, B. Giebels, J. F. Glicenstein, B. Glück, P. Goret, C. Hadjichristidis, D. Hauser, M. Hauser, S. Heinz, G. Heinzelmann, G. Henri, G. Hermann, J. A. Hinton, A. Hoffmann, W. Hofmann, M. Holleran, S. Hoppe, D. Horns, A. Jacholkowska, O. C. de Jager, I. Jung, K. Katarzyński, S. Kaufmann, E. Kendziorra, M. Kerschhaggl, D. Khangulyan, B. Khélifi, D. Keogh, Nu. Komin, K. Kosack, G. Lamanna, J.-P. Lenain, T. Lohse, V. Marandon, J. M. Martin, O. Martineau-Huynh, A. Marcowith, D. Maurin, T. J. L. McComb, M. C. Medina, R. Moderski, E. Moulin, M. Naumann-Godo, M. de Naurois, D. Nedbal, D. Nekrassov, J. Niemiec, S. J. Nolan, S. Ohm, J.-F. Olive, E. de Oña Wilhelmi, K. J. Orford, J. L. Osborne, M. Ostrowski, M. Panter, G. Pedaletti, G. Pelletier, P.-O. Petrucci, S. Pita, G. Pühlhofer, M. Punch, A. Quirrenbach, B. C. Raubenheimer, M. Raue, S. M. Rayner, M. Renaud, F. Rieger, J. Ripken, L. Rob, S. Rosier-Lees, G. Rowell, B. Rudak, C. B. Rulten, J. Ruppel, V. Sahakian, A. Santangelo, R. Schlickeiser, F. M. Schöck, R. Schröder, U. Schwanke, S. Schwarzburg, S. Schwemmer, A. Shalchi, J. L. Skilton, H. Sol, D. Spangler, Ł. Stawarz, R. Steenkamp, C. Stegmann, G. Superina, P. H. Tam, J.-P. Tavernet, R. Terrier, O. Tibolla, C. van Eldik, G. Vasileiadis, C. Venter, J. P. Vialle, P. Vincent, M. Vivier, H. J. Völk, F. Volpe, S. J. Wagner, M. Ward, A. A. Zdziarski, A. Zech, Centre d'étude spatiale des rayonnements (CESR), Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, AstroParticule et Cosmologie (APC (UMR_7164)), Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Laboratoire Univers et Théories (LUTH (UMR_8102)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Laboratoire d'Astrophysique de Grenoble (LAOG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Pierre et Marie Curie - Paris 6 (UPMC), Laboratoire Leprince-Ringuet (LLR), Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Laboratoire d'Annecy de Physique des Particules (LAPP), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), APC - Astrophysique des Hautes Energies (APC - AHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Dipartimento di Astronomia, Universita degli Studi di Bologna, Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO)-Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), Laboratoire de Physique Théorique et Astroparticules (LPTA), Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), HESS, Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), 10859748 - Holleran, Mathew, 12006653 - Venter, Christo, 10179240 - Raubenheimer, Barend Christoffel, 13235176 - Büsching, Ingo, 10065857 - De Jager, Ocker Cornelis, Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7), PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Annecy de Physique des Particules (LAPP/Laboratoire d'Annecy-le-Vieux de Physique des Particules), Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Dipartimento di Astronomia, Universita degli Studi di Bologna, Università di Bologna [Bologna] (UNIBO)-Università di Bologna [Bologna] (UNIBO)-AstroParticule et Cosmologie (APC (UMR_7164)), and PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris
Subjects: [SDU.ASTR.CO]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Event horizon, Astrophysics::High Energy Astrophysical Phenomena, Population, FOS: Physical sciences, Flux, Astrophysics, gamma-rays:observations, 01 natural sciences, law.invention, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Coincident, law, 0103 physical sciences, education, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Physics, individuals: Sgr A* [X-rays], Supermassive black hole, education.field_of_study, 010308 nuclear & particles physics, Astrophysics (astro-ph), observations [gamma rays], Astronomy and Astrophysics, X-rays:individual sources:Sgr A, Particle acceleration, Sagittarius A, Space and Planetary Science, individuals: Sgr $A^{\star }$ [X-rays], Flare
Abstract: The rapidly varying (~10 minute timescale) non-thermal X-ray emission observed from Sgr A* implies that particle acceleration is occuring close to the event horizon of the supermassive black hole. The TeV gamma-ray source HESS J1745-290 is coincident with Sgr A* and may be closely related to its X-ray emission. Simultaneous X-ray and TeV observations are required to elucidate the relationship between these objects. We report on joint H.E.S.S./Chandra observations performed in July 2005, during which an X-ray flare was detected. Despite a factor of 9 increase in the X-ray flux of Sgr A*, no evidence is found for an increase in the TeV gamma-ray flux from this region. We find that an increase in the gamma-ray flux of a factor of 2 or greater can be excluded at a confidence level of 99%. This finding disfavours scenarios in which the keV and TeV emission are associated with the same population of accelerated particles and in which the bulk of the gamma-ray emission is produced within ~10^{14} cm (~100 R_S) of the supermassive black hole., 5 pages, 2 figures
Published: 2008

26. Modeling of strongly-nonlinear wave propagation using the extended Rankine-Hugoniot shock relations

Author: Woosup Shim, W.-S. Ohm, and Jae-Wan Lee
Subjects: Shock wave, Algebraic equation, Flow (mathematics), Discretization, Mathematical analysis, Rarefaction, Particle velocity, Shock (mechanics), Mathematics, Burgers' equation
Abstract: This paper presents a computational scheme solely based on the Rankine-Hugoniot shock relations to describe the propagation of strongly-nonlinear waves in fluids, the amplitude of which is so great that second-order approximations such as the weak shock theory and the Burgers equation do not apply. The Rankine-Hugoniot relations are three algebraic equations connecting the flow variables (pressure, density, particle velocity, and energy) across a shock. What is not well known is that the Rankine-Hugoniot relations can be used to compute the nonlinear evolution of the continuous segment of a wave, if the continuous segment can be approximated by a succession of infinitesimal compression shocks [Ya. B. Zel’dovich and Yu. P. Raizer, Physics of Shock Waves and High-Temperature Hydrodynamic Phenomena (Dover, New York, 2002), pp. 85-86]. We further extend this idea to the other continuous segment that can be discretized into a series of infinitesimal rarefaction shocks. The discretization of a waveform and the ...
Published: 2015

27. Derivation of the nonlinearity parameter B/A of saturated, unconsolidated marine sediments via a statistical approach

Author: Hunki Lee, O.-C. Kwon, W.-S. Ohm, and Eunghwy Noh
Subjects: Nonlinear system, Materials science, Contact mechanics, Homogeneous, Quadratic nonlinearity, food and beverages, Mineralogy, Suspension (chemistry)
Abstract: Marine sediments are known to exhibit the nonlinearity parameter B/A that is much greater than that of homogeneous fluids and solids. The enormous value of B/A is particularly sensitive to the state of grain contacts. Although there exists a large body of literature that deals with the B/A of marine sediments, few studies have addressed how the random nature of grain contacts affects B/A. Here, we develop a model for the B/A of saturated, unconsolidated marine sediments, which accounts for random grain contacts. The number of contacts per grain and the distribution of contact stress between grains are treated statistically. The quadratic nonlinearity of the equivalent suspension of grains and the interstitial fluid is then combined with the nonlinearity arising from the random Hertzian contacts to produce the effective B/A of marine sediments.
Published: 2015

28. Clustered regularly interspaced short palindromic repeats-associated protein 9: A new era in targeted molecular therapy.

Author: Vishnupriyan, K., Prakash, S. Ohm, and Kavitha, M.
Subjects: *PROTEINS, *MOLECULAR biology, *GENES, *CRISPRS, *CANCER, *ONCOGENES
Abstract: In molecular biology to understand the critical role/s played by certain gene products, the encoding genes are often disrupted, and the effects are further analyzed to ascertain the exact function of the gene/protein in the development of the organisms. Recently emerged gene editing technique revolutionized the field of biology to study the pathology of various diseases and in the discovery of drugs. Clustered regularly interspaced short palindromic repeats (CRISPR) and CRISPR-associated protein 9 (CRISPR-Cas9) attracted the attention of the World due to its impeccable potential in research and therapeutic applications. Unlike other techniques, CRISPR can deactivate a gene without interfering with intracellular mechanisms. It can be used to understand the genetic and epigenetic aspects of various diseases especially cancer. CRISPR can be used to induce specific mutations in oncogenes and tumor suppressor genes in cell lines to model the cancers to understand the pathology and to develop effective drugs. CRISPR-Cas9 holds the promising potential to treat genetic diseases such as Duchenne muscular dystrophy, Hemophilia, β-Thalassemia, and cystic fibrosis. However, there are some challenges and concerns which needs to addressed. In this review, we discuss on the origin of CRISPR-Cas9 technology, how it works, genome/nongenome editing for targeted molecular therapy and future directions. [ABSTRACT FROM AUTHOR]
Published: 2019

29. Discovery of TeV gamma-ray emission from PKS 0447-439 and derivation of an upper limit on its redshift

Author: H. E.S.S. Collaboration, A. Abramowski, F. Acero, A. G. Akhperjanian, G. Anton, S. Balenderan, A. Balzer, A. Barnacka, Y. Becherini, J. Becker Tjus, B. Behera, K. Bernlöhr, E. Birsin, J. Biteau, A. Bochow, C. Boisson, J. Bolmont, P. Bordas, J. Brucker, F. Brun, P. Brun, T. Bulik, S. Carrigan, S. Casanova, M. Cerruti, P. M. Chadwick, R. C. G. Chaves, A. Cheesebrough, S. Colafrancesco, G. Cologna, J. Conrad, C. Couturier, M. Dalton, M. K. Daniel, I. D. Davids, B. Degrange, C. Deil, P. deWilt, H. J. Dickinson, A. Djannati-Ataï, W. Domainko, L. O’C. Drury, G. Dubus, K. Dutson, J. Dyks, M. Dyrda, K. Egberts, P. Eger, P. Espigat, L. Fallon, C. Farnier, S. Fegan, F. Feinstein, M. V. Fernandes, D. Fernandez, A. Fiasson, G. Fontaine, A. Förster, M. Füßling, M. Gajdus, Y. A. Gallant, T. Garrigoux, H. Gast, B. Giebels, J. F. Glicenstein, B. Glück, D. Göring, M.-H. Grondin, M. Grudzińska, S. Häffner, J. D. Hague, J. Hahn, D. Hampf, J. Harris, S. Heinz, G. Heinzelmann, G. Henri, G. Hermann, A. Hillert, J. A. Hinton, W. Hofmann, P. Hofverberg, M. Holler, D. Horns, A. Jacholkowska, C. Jahn, M. Jamrozy, I. Jung, M. A. Kastendieck, K. Katarzyński, U. Katz, S. Kaufmann, B. Khélifi, S. Klepser, D. Klochkov, W. Kluźniak, T. Kneiske, D. Kolitzus, Nu. Komin, K. Kosack, R. Kossakowski, F. Krayzel, P. P. Krüger, H. Laffon, G. Lamanna, J. Lefaucheur, M. Lemoine-Goumard, J.-P. Lenain, D. Lennarz, T. Lohse, A. Lopatin, C.-C. Lu, V. Marandon, A. Marcowith, J. Masbou, G. Maurin, N. Maxted, M. Mayer, T. J. L. McComb, M. C. Medina, J. Méhault, U. Menzler, R. Moderski, M. Mohamed, E. Moulin, C. L. Naumann, M. Naumann-Godo, M. de Naurois, D. Nedbal, N. Nguyen, J. Niemiec, S. J. Nolan, S. Ohm, E. de Oña Wilhelmi, B. Opitz, M. Ostrowski, I. Oya, M. Panter, R. D. Parsons, M. Paz Arribas, N. W. Pekeur, G. Pelletier, J. Perez, P.-O. Petrucci, B. Peyaud, S. Pita, G. Pühlhofer, M. Punch, A. Quirrenbach, S. Raab, M. Raue, A. Reimer, O. Reimer, M. Renaud, R. de los Reyes, F. Rieger, J. Ripken, L. Rob, S. Rosier-Lees, G. Rowell, B. Rudak, C. B. Rulten, V. Sahakian, D. A. Sanchez, A. Santangelo, R. Schlickeiser, A. Schulz, U. Schwanke, S. Schwarzburg, S. Schwemmer, F. Sheidaei, J. L. Skilton, H. Sol, G. Spengler, Ł. Stawarz, R. Steenkamp, C. Stegmann, F. Stinzing, K. Stycz, I. Sushch, A. Szostek, J.-P. Tavernet, R. Terrier, M. Tluczykont, C. Trichard, K. Valerius, C. van Eldik, G. Vasileiadis, C. Venter, A. Viana, P. Vincent, H. J. Völk, F. Volpe, S. Vorobiov, M. Vorster, S. J. Wagner, M. Ward, R. White, A. Wierzcholska, D. Wouters, M. Zacharias, A. Zajczyk, A. A. Zdziarski, A. Zech, H.-S. Zechlin, D. Pelat, H.E.S.S. Collaboration, 12006653 - Venter, Christo, 11005394 - Krüger, Petrus Paulus, 22050574 - Pekeur, Nicolette Whilna, 12792322 - Vorster, Michael Johannes, 22164405 - Sheidaei, Farzaneh, 23909196 - Casanova, Sabrina, Laboratoire Univers et Particules de Montpellier (LUPM), Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Leprince-Ringuet (LLR), Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), AstroParticule et Cosmologie (APC (UMR_7164)), Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Pierre et Marie Curie - Paris 6 (UPMC), APC - Astrophysique des Hautes Energies (APC - AHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Dipartimento di Astronomia, Universita degli Studi di Bologna, Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO)-Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), Laboratoire d'Annecy de Physique des Particules (LAPP), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), GLAST, Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), HESS, Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1 (UB)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Université de Montpellier (UM)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7), PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Dipartimento di Astronomia, Universita degli Studi di Bologna, Università di Bologna [Bologna] (UNIBO)-Università di Bologna [Bologna] (UNIBO), and Laboratoire d'Annecy de Physique des Particules (LAPP/Laboratoire d'Annecy-le-Vieux de Physique des Particules)
Subjects: [PHYS.ASTR.HE]Physics [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE], galaxies. [Gamma rays], active [Galaxies], Ciencias Físicas, Astrophysics::High Energy Astrophysical Phenomena, galaxies: active, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 7. Clean energy, 01 natural sciences, purl.org/becyt/ford/1 [https], Gamma ray galaxies, 0103 physical sciences, gamma rays: galaxies, Radiation mechanisms, Blazar, 010303 astronomy & astrophysics, Physics, Non thermal mechanisms, High Energy Astrophysical Phenomena (astro-ph.HE), non-thermal [Radiation mechanisms], individual: PKS 0447-439 [BL Lacertae objects], 010308 nuclear & particles physics, [SDU.ASTR.HE]Sciences of the Universe [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE], Gamma ray, Astronomy and Astrophysics, purl.org/becyt/ford/1.3 [https], radiation mechanisms: non-thermal, Light curve, Cherenkov Telescope Array, BL Lacertae objects: individual: PKS 0447-439, Redshift, Astronomía, Extragalactic background light, Space and Planetary Science, galaxies [gamma rays], Active galaxies, BL Lacertae objects, ddc:520, Spectral energy distribution, High Energy Physics::Experiment, Astrophysics - High Energy Astrophysical Phenomena, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], CIENCIAS NATURALES Y EXACTAS, Fermi Gamma-ray Space Telescope
Abstract: Very high-energy gamma-ray emission from PKS 0447-439 was detected with the H.E.S.S. Cherenkov telescope array in December 2009. This blazar is one of the brightest extragalactic objects in the Fermi Bright Source List and has a hard spectrum in the MeV to GeV range. In the TeV range, a photon index of 3.89 +- 0.37 (stat) +- 0.22 (sys) and a flux normalisation at 1 TeV, Phi(1 TeV) = (3.5 +- 1.1 (stat) +- 0.9 (sys)) x 10^{-13} cm^{-2} s^{-1} TeV^{-1}, were found. The detection with H.E.S.S. triggered observations in the X-ray band with the Swift and RXTE telescopes. Simultaneous UV and optical data from Swift UVOT and data from the optical telescopes ATOM and ROTSE are also available. The spectrum and light curve measured with H.E.S.S. are presented and compared to the multi-wavelength data at lower energies. A rapid flare is seen in the Swift XRT and RXTE data, together with a flux variation in the UV band, at a time scale of the order of one day. A firm upper limit of z < 0.59 on the redshift of PKS 0447-439 is derived from the combined Fermi-LAT and H.E.S.S. data, given the assumptions that there is no upturn in the intrinsic spectrum above the Fermi-LAT energy range and that absorption on the Extragalactic Background Light (EBL) is not weaker than the lower limit provided by current models. The spectral energy distribution is well described by a simple one-zone Synchrotron Self-Compton (SSC) scenario, if the redshift of the source is less than z, Comment: 14 pages, 10 figures, accepted for publication in A&A
Published: 2013

30. Agile Firm Organisation and Upgrading in the Greater Pearl River Delta

Author: Daniel Schiller, S. Ohm, Wenying Fu, Ingo Liefner, R. Soltwedel, J. Revilla-Diez, Stefan Hennemann, Wan-Hsin Liu, P. Hartmann, Frank Bickenbach, Frauke Kraas, and S. Meyer
Subjects: Pearl river delta, business.industry, Corporate governance, Production (economics), business, China, Industrial organization, Agile software development
Abstract: This chapter analyses an original firm-level dataset collected by our own Hong Kong (HK) Company Survey 2007 to investigate agility patterns applied by HK companies in the Pearl River Delta (PRD) in organising relations to their producers in the PRD and their customers. It also investigates the role of informality proxied by personal relationships for companies in the PRD in governing their production as well as their innovation activities, which have gained greatly in importance in the PRD in the new century. Our findings suggest that different agility patterns can be identified that are applied by companies to organise their relations to their producers and customers. Moreover, the findings show that companies generally tend to vertically integrate their production or innovation activities rather than carrying out such activities under a cooperative governance structure. With regard to cooperative governance structures, there is evidence of a complementary relationship between the importance of informality proxied by personal relationships and the importance of cooperative governance structures both for production and for innovation.
Published: 2013

31. H.E.S.S. observations of the massive stellar cluster Westerlund 1

Author: E. de Oña Wilhelmi, Gavin Rowell, Olaf Reimer, S. Ohm, M. de Naurois, Dieter Horns, A. Marcowith, and M. V. Fernandes
Subjects: Physics, Cluster (physics), Astrophysics
Published: 2011

32. ChemInform Abstract: A Versatile Synthesis for 1,4-Dienes: Use of Vinyl Ethers as Vinyl Cation Equivalents

Author: S. Ohm, E. + Baeuml, and Herbert Mayr
Subjects: Chemistry, Organic chemistry, General Medicine, Vinyl cation
Published: 2010

33. HESS observations of $\gamma$-ray bursts in 2003-2007

Author: F. Aharonian, A. G. Akhperjanian, U. Barres de Almeida, A. R. Bazer-Bachi, B. Behera, W. Benbow, K. Bernlöhr, C. Boisson, A. Bochow, V. Borrel, I. Braun, E. Brion, J. Brucker, P. Brun, R. Bühler, T. Bulik, I. Büsching, T. Boutelier, S. Carrigan, P. M. Chadwick, A. Charbonnier, R. C. G. Chaves, A. Cheesebrough, L.-M. Chounet, A. C. Clapson, G. Coignet, M. Dalton, B. Degrange, C. Deil, H. J. Dickinson, A. Djannati-Ataï, W. Domainko, L. O'C. Drury, F. Dubois, G. Dubus, J. Dyks, M. Dyrda, K. Egberts, D. Emmanoulopoulos, P. Espigat, C. Farnier, F. Feinstein, A. Fiasson, A. Förster, G. Fontaine, M. Füßling, S. Gabici, Y. A. Gallant, L. Gérard, B. Giebels, J. F. Glicenstein, B. Glück, P. Goret, C. Hadjichristidis, D. Hauser, M. Hauser, S. Heinz, G. Heinzelmann, G. Henri, G. Hermann, J. A. Hinton, A. Hoffmann, W. Hofmann, M. Holleran, S. Hoppe, D. Horns, A. Jacholkowska, O. C. de Jager, I. Jung, K. Katarzyński, S. Kaufmann, E. Kendziorra, M. Kerschhaggl, D. Khangulyan, B. Khélifi, D. Keogh, Nu. Komin, K. Kosack, G. Lamanna, J.-P. Lenain, T. Lohse, V. Marandon, J. M. Martin, O. Martineau-Huynh, A. Marcowith, D. Maurin, T. J. L. McComb, M. C. Medina, R. Moderski, E. Moulin, M. Naumann-Godo, M. de Naurois, D. Nedbal, D. Nekrassov, J. Niemiec, S. J. Nolan, S. Ohm, J.-F. Olive, E. de Oña Wilhelmi, K. J. Orford, J. L. Osborne, M. Ostrowski, M. Panter, G. Pedaletti, G. Pelletier, P.-O. Petrucci, S. Pita, G. Pühlhofer, M. Punch, A. Quirrenbach, B. C. Raubenheimer, M. Raue, S. M. Rayner, M. Renaud, F. Rieger, J. Ripken, L. Rob, S. Rosier-Lees, G. Rowell, B. Rudak, C. B. Rulten, J. Ruppel, V. Sahakian, A. Santangelo, R. Schlickeiser, F. M. Schöck, R. Schröder, U. Schwanke, S. Schwarzburg, S. Schwemmer, A. Shalchi, J. L. Skilton, H. Sol, D. Spangler, Ł. Stawarz, R. Steenkamp, C. Stegmann, G. Superina, P. H. Tam, J.-P. Tavernet, R. Terrier, O. Tibolla, C. van Eldik, G. Vasileiadis, C. Venter, L. Venter, J. P. Vialle, P. Vincent, M. Vivier, H. J. Völk, F. Volpe, S. J. Wagner, M. Ward, A. A. Zdziarski, and A. Zech
Subjects: Physics, 010308 nuclear & particles physics, Astrophysics::High Energy Astrophysical Phenomena, Astrophysics::Instrumentation and Methods for Astrophysics, Flux, bursts [gamma rays], observations [gamma rays], Astronomy and Astrophysics, Astrophysics, Photon energy, 01 natural sciences, Redshift, Space and Planetary Science, 0103 physical sciences, Background light, Gamma-ray burst, 010303 astronomy & astrophysics, Cherenkov radiation
Abstract: Very-high-energy (VHE; >~100 GeV) gamma-rays are expected from gamma-ray bursts (GRBs) in some scenarios. Exploring this photon energy regime is necessary for understanding the energetics and properties of GRBs. GRBs have been one of the prime targets for the H.E.S.S. experiment, which makes use of four Imaging Atmospheric Cherenkov Telescopes (IACTs) to detect VHE gamma-rays. Dedicated observations of 32 GRB positions were made in the years 2003-2007 and a search for VHE gamma-ray counterparts of these GRBs was made. Depending on the visibility and observing conditions, the observations mostly start minutes to hours after the burst and typically last two hours. Results from observations of 22 GRB positions are presented and evidence of a VHE signal was found neither in observations of any individual GRBs, nor from stacking data from subsets of GRBs with higher expected VHE flux according to a model-independent ranking scheme. Upper limits for the VHE gamma-ray flux from the GRB positions were derived. For those GRBs with measured redshifts, differential upper limits at the energy threshold after correcting for absorption due to extra-galactic background light are also presented.
Published: 2009

34. Very high energy gamma-ray observations of the galaxy clusters Abell 496 and Abell 85 with H.E.S.S

Author: F. Aharonian, A. G. Akhperjanian, G. Anton, U. Barres de Almeida, A. R. Bazer-Bachi, Y. Becherini, B. Behera, K. Bernlöhr, C. Boisson, A. Bochow, V. Borrel, I. Braun, E. Brion, J. Brucker, P. Brun, R. Bühler, T. Bulik, I. Büsching, T. Boutelier, P. M. Chadwick, A. Charbonnier, R. C. G. Chaves, A. Cheesebrough, L.-M. Chounet, A. C. Clapson, G. Coignet, M. Dalton, M. K. Daniel, B. Degrange, C. Deil, H. J. Dickinson, A. Djannati-Ataï, W. Domainko, L. O'C. Drury, F. Dubois, G. Dubus, J. Dyks, M. Dyrda, K. Egberts, D. Emmanoulopoulos, P. Espigat, C. Farnier, F. Feinstein, A. Fiasson, A. Förster, G. Fontaine, M. Füßling, S. Gabici, Y. A. Gallant, L. Gérard, B. Giebels, J. F. Glicenstein, B. Glück, P. Goret, D. Hauser, M. Hauser, S. Heinz, G. Heinzelmann, G. Henri, G. Hermann, J. A. Hinton, A. Hoffmann, W. Hofmann, M. Holleran, S. Hoppe, D. Horns, A. Jacholkowska, O. C. de Jager, I. Jung, K. Katarzyński, U. Katz, S. Kaufmann, E. Kendziorra, M. Kerschhaggl, D. Khangulyan, B. Khélifi, D. Keogh, Nu. Komin, K. Kosack, G. Lamanna, J.-P. Lenain, T. Lohse, V. Marandon, J. M. Martin, O. Martineau-Huynh, A. Marcowith, D. Maurin, T. J. L. McComb, M. C. Medina, R. Moderski, E. Moulin, M. Naumann-Godo, M. de Naurois, D. Nedbal, D. Nekrassov, J. Niemiec, S. J. Nolan, S. Ohm, J.-F. Olive, E. de Oña Wilhelmi, K. J. Orford, M. Ostrowski, M. Panter, M. Paz Arribas, G. Pedaletti, G. Pelletier, P.-O. Petrucci, S. Pita, G. Pühlhofer, M. Punch, A. Quirrenbach, B. C. Raubenheimer, M. Raue, S. M. Rayner, M. Renaud, F. Rieger, J. Ripken, L. Rob, S. Rosier-Lees, G. Rowell, B. Rudak, C. B. Rulten, J. Ruppel, V. Sahakian, A. Santangelo, R. Schlickeiser, F. M. Schöck, R. Schröder, U. Schwanke, S. Schwarzburg, S. Schwemmer, A. Shalchi, J. L. Skilton, H. Sol, D. Spangler, Ł. Stawarz, R. Steenkamp, C. Stegmann, G. Superina, A. Szostek, P. H. Tam, J.-P. Tavernet, R. Terrier, O. Tibolla, C. van Eldik, G. Vasileiadis, C. Venter, L. Venter, J. P. Vialle, P. Vincent, M. Vivier, H. J. Völk, F. Volpe, S. J. Wagner, M. Ward, A. A. Zdziarski, A. Zech, Centre d'étude spatiale des rayonnements (CESR), Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, AstroParticule et Cosmologie (APC (UMR_7164)), Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Laboratoire Univers et Théories (LUTH (UMR_8102)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Laboratoire d'Astrophysique de Grenoble (LAOG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Leprince-Ringuet (LLR), Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Laboratoire d'Annecy de Physique des Particules (LAPP), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), APC - Astrophysique des Hautes Energies (APC - AHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Dipartimento di Astronomia, Universita degli Studi di Bologna, Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO)-Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), Laboratoire de Physique Théorique et Astroparticules (LPTA), Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Pierre et Marie Curie - Paris 6 (UPMC), HESS, Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7), PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Annecy de Physique des Particules (LAPP/Laboratoire d'Annecy-le-Vieux de Physique des Particules), Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Dipartimento di Astronomia, Universita degli Studi di Bologna, Università di Bologna [Bologna] (UNIBO)-Università di Bologna [Bologna] (UNIBO)-AstroParticule et Cosmologie (APC (UMR_7164)), PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO)
Subjects: [SDU.ASTR.CO]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Astrophysics::High Energy Astrophysical Phenomena, Flux, FOS: Physical sciences, Cosmic ray, IACT, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Gamma rays: observations, 01 natural sciences, 7. Clean energy, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], 0103 physical sciences, Cluster (physics), 010303 astronomy & astrophysics, Galaxy cluster, Abell 85, Physics, Accretion (meteorology), 010308 nuclear & particles physics, Astrophysics (astro-ph), Gamma ray, observations [gamma rays], Astronomy and Astrophysics, Galaxy, Space and Planetary Science, clusters: individual: Abell 496 [galaxies], Galaxies: clusters: individual: Abell 496, clusters: individual: Abell 85 [galaxies]
Abstract: Aims: The nearby galaxy clusters Abell 496 and Abell 85 are studied in the very high energy (VHE, E > 100 GeV) band to investigate VHE cosmic rays (CRs) in this class of objects which are the largest gravitationally bound systems in the Universe. Methods: H.E.S.S., an array of four Imaging Atmospheric Cherenkov Telescopes (IACT), is used to observe the targets in the range of VHE gamma rays. Results: No significant gamma-ray signal is found at the respective position of the two clusters with several different source size assumptions for each target. In particular, emission regions corresponding to the high density core, to the extension of the entire X-ray emission in these clusters, and to the very extended region where the accretion shock is expected, are investigated. Upper limits are derived for the gamma-ray flux at energies E>570 GeV for Abell 496 and E>460 GeV for Abell 85. Conclusions: From the non-detection in VHE gamma rays, upper limits on the total energy of hadronic CRs in the clusters are calculated. If the cosmic-ray energy density follows the large scale gas density profile, the limit on the fraction of energy in these non-thermal particles with respect to the total thermal energy of the intra-cluster medium (ICM) is 51% for Abell 496 and only 8% for Abell 85 due to its larger mass and higher gas density. These upper limits are compared with theoretical estimates. They predict about ~10% of the thermal energy of the ICM in non-thermal particles. The observations presented here can constrain these predictions especially for the case of the Abell 85 cluster., 11 pages, 4 figures, accepted for publication in A&A
Published: 2009

35. Simultaneous multiwavelength observations of the second exceptional $\gamma$-ray flare of PKS 2155–304 in July 2006

Author: F. Aharonian, A. G. Akhperjanian, G. Anton, U. Barres de Almeida, A. R. Bazer-Bachi, Y. Becherini, B. Behera, W. Benbow, K. Bernlöhr, C. Boisson, A. Bochow, V. Borrel, E. Brion, J. Brucker, P. Brun, R. Bühler, T. Bulik, I. Büsching, T. Boutelier, P. M. Chadwick, A. Charbonnier, R. C. G. Chaves, A. Cheesebrough, L.-M. Chounet, A. C. Clapson, G. Coignet, L. Costamante, M. Dalton, M. K. Daniel, I. D. Davids, B. Degrange, C. Deil, H. J. Dickinson, A. Djannati-Ataï, W. Domainko, L. O'C. Drury, F. Dubois, G. Dubus, J. Dyks, M. Dyrda, K. Egberts, D. Emmanoulopoulos, P. Espigat, C. Farnier, F. Feinstein, A. Fiasson, A. Förster, G. Fontaine, M. Füßling, S. Gabici, Y. A. Gallant, L. Gérard, B. Giebels, J. F. Glicenstein, B. Glück, P. Goret, D. Göhring, D. Hauser, M. Hauser, S. Heinz, G. Heinzelmann, G. Henri, G. Hermann, J. A. Hinton, A. Hoffmann, W. Hofmann, M. Holleran, S. Hoppe, D. Horns, A. Jacholkowska, O. C. de Jager, C. Jahn, I. Jung, K. Katarzyński, U. Katz, S. Kaufmann, E. Kendziorra, M. Kerschhaggl, D. Khangulyan, B. Khélifi, D. Keogh, W. Kluźniak, T. Kneiske, Nu. Komin, K. Kosack, G. Lamanna, J.-P. Lenain, T. Lohse, V. Marandon, J. M. Martin, O. Martineau-Huynh, A. Marcowith, D. Maurin, T. J. L. McComb, M. C. Medina, R. Moderski, L. A. G. Monard, E. Moulin, M. Naumann-Godo, M. de Naurois, D. Nedbal, D. Nekrassov, J. Niemiec, S. J. Nolan, S. Ohm, J.-F. Olive, E. de Oña Wilhelmi, K. J. Orford, M. Ostrowski, M. Panter, M. Paz Arribas, G. Pedaletti, G. Pelletier, P.-O. Petrucci, S. Pita, G. Pühlhofer, M. Punch, A. Quirrenbach, B. C. Raubenheimer, M. Raue, S. M. Rayner, M. Renaud, F. Rieger, J. Ripken, L. Rob, S. Rosier-Lees, G. Rowell, B. Rudak, C. B. Rulten, J. Ruppel, V. Sahakian, A. Santangelo, R. Schlickeiser, F. M. Schöck, R. Schröder, U. Schwanke, S. Schwarzburg, S. Schwemmer, A. Shalchi, M. Sikora, J. L. Skilton, H. Sol, D. Spangler, Ł. Stawarz, R. Steenkamp, C. Stegmann, G. Superina, A. Szostek, P. H. Tam, J.-P. Tavernet, R. Terrier, O. Tibolla, M. Tluczykont, C. van Eldik, G. Vasileiadis, C. Venter, L. Venter, J. P. Vialle, P. Vincent, M. Vivier, H. J. Völk, F. Volpe, S. J. Wagner, M. Ward, A. A. Zdziarski, A. Zech, Centre d'étude spatiale des rayonnements (CESR), Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, AstroParticule et Cosmologie (APC (UMR_7164)), Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Laboratoire Univers et Théories (LUTH (UMR_8102)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7), Laboratoire d'Astrophysique de Grenoble (LAOG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Pierre et Marie Curie - Paris 6 (UPMC), Laboratoire Leprince-Ringuet (LLR), Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Laboratoire d'Annecy de Physique des Particules (LAPP), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), APC - Astrophysique des Hautes Energies (APC - AHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Dipartimento di Astronomia, Universita degli Studi di Bologna, Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO)-Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), Laboratoire de Physique Théorique et Astroparticules (LPTA), Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), HESS, Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7), PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Annecy de Physique des Particules (LAPP/Laboratoire d'Annecy-le-Vieux de Physique des Particules), Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Dipartimento di Astronomia, Universita degli Studi di Bologna, Università di Bologna [Bologna] (UNIBO)-Università di Bologna [Bologna] (UNIBO)-AstroParticule et Cosmologie (APC (UMR_7164)), and PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris
Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO), [SDU.ASTR.CO]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Astrophysics::High Energy Astrophysical Phenomena, Phase (waves), FOS: Physical sciences, Astrophysics, 01 natural sciences, Spectral line, law.invention, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Flux (metallurgy), law, 0103 physical sciences, 010303 astronomy & astrophysics, PKS 2155-304, Physics, 010308 nuclear & particles physics, Gamma ray, observations [gamma rays], Astronomy and Astrophysics, Light curve, galaxies [X-rays], Space and Planetary Science, active [galaxies], BL Lacertae objects: individual: PKS 2155–304 [galaxies], Astrophysics - Cosmology and Nongalactic Astrophysics, Flare, BL Lac object
Abstract: Simultaneous HESS/CHANDRA/optical observations were performed on the BL Lac object PKS 2155-304 in the night of July 29-30 2006, when the source underwent its second major gamma-ray outburst in Summer 2006. This event took place about 44 hours after the July 28 outburst, known for its ultrafast variability. An unprecedented 6 to 8 hours of uninterrupted coverage was achieved, with spectra and light curves measured down to 7 and 2-minute timescales, respectively. The gamma-ray flux reached a maximum of 11x the Crab flux (>400 GeV), with rise/decay timescales of ~1 hour, plus a few smaller-amplitude flares superimposed on the decaying phase. The emission in the X-ray and VHE bands is strongly correlated, both in flux and spectrum, with no evidence of lags. The VHE spectrum shows a curvature that is variable with time and stronger at higher fluxes. The huge VHE variations (22x) are only accompanied by small-amplitude X-ray and optical variations (factor 2 and 15% respectively). The source has shown for the first time in an HBL a large Compton dominance (L_C/L_S ~10) -- rapidly evolving -- and a cubic relation between VHE and X-ray flux variations, during a decaying phase. These results challenge the common scenarios for the TeV-blazar emission., 22 pages, 16 figures, accepted for publication in A&A
Published: 2009

36. Discovery of very high energy $\gamma$-ray emission from Centaurus A with H.E.S.S

Author: F. Aharonian, A. G. Akhperjanian, G. Anton, U. Barres de Almeida, A. R. Bazer-Bachi, Y. Becherini, B. Behera, W. Benbow, K. Bernlöhr, C. Boisson, A. Bochow, V. Borrel, E. Brion, J. Brucker, P. Brun, R. Bühler, T. Bulik, I. Büsching, T. Boutelier, P. M. Chadwick, A. Charbonnier, R. C. G. Chaves, A. Cheesebrough, L.-M. Chounet, A. C. Clapson, G. Coignet, M. Dalton, M. K. Daniel, I. D. Davids, B. Degrange, C. Deil, H. J. Dickinson, A. Djannati-Ataï, W. Domainko, L. O'C. Drury, F. Dubois, G. Dubus, J. Dyks, M. Dyrda, K. Egberts, D. Emmanoulopoulos, P. Espigat, C. Farnier, F. Feinstein, A. Fiasson, A. Förster, G. Fontaine, M. Füßling, S. Gabici, Y. A. Gallant, L. Gérard, B. Giebels, J.-F. Glicenstein, B. Glück, P. Goret, D. Göhring, D. Hauser, M. Hauser, S. Heinz, G. Heinzelmann, G. Henri, G. Hermann, J. A. Hinton, A. Hoffmann, W. Hofmann, M. Holleran, S. Hoppe, D. Horns, A. Jacholkowska, O. C. de Jager, C. Jahn, I. Jung, K. Katarzyński, U. Katz, S. Kaufmann, E. Kendziorra, M. Kerschhaggl, D. Khangulyan, B. Khélifi, D. Keogh, W. Kluźniak, T. Kneiske, Nu. Komin, K. Kosack, G. Lamanna, I. J. Latham, J.-P. Lenain, T. Lohse, V. Marandon, J. M. Martin, O. Martineau-Huynh, A. Marcowith, D. Maurin, T. J. L. McComb, M. C. Medina, R. Moderski, E. Moulin, M. Naumann-Godo, M. de Naurois, D. Nedbal, D. Nekrassov, J. Niemiec, S. J. Nolan, S. Ohm, J.-F. Olive, E. de Oña Wilhelmi, K. J. Orford, M. Ostrowski, M. Panter, M. Paz Arribas, G. Pedaletti, G. Pelletier, P.-O. Petrucci, S. Pita, G. Pühlhofer, M. Punch, A. Quirrenbach, B. C. Raubenheimer, M. Raue, S. M. Rayner, M. Renaud, F. Rieger, J. Ripken, L. Rob, S. Rosier-Lees, G. Rowell, B. Rudak, C. B. Rulten, J. Ruppel, V. Sahakian, A. Santangelo, R. Schlickeiser, F. M. Schöck, R. Schröder, U. Schwanke, S. Schwarzburg, S. Schwemmer, A. Shalchi, M. Sikora, J. L. Skilton, H. Sol, D. Spangler, Ł. Stawarz, R. Steenkamp, C. Stegmann, G. Superina, A. Szostek, P. H. Tam, J.-P. Tavernet, R. Terrier, O. Tibolla, M. Tluczykont, C. van Eldik, G. Vasileiadis, C. Venter, L. Venter, J. P. Vialle, P. Vincent, J. Vink, M. Vivier, H. J. Völk, F. Volpe, S. J. Wagner, M. Ward, A. A. Zdziarski, A. Zech, Centre d'étude spatiale des rayonnements (CESR), Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, AstroParticule et Cosmologie (APC (UMR_7164)), Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Laboratoire Univers et Théories (LUTH (UMR_8102)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Laboratoire d'Astrophysique de Grenoble (LAOG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Pierre et Marie Curie - Paris 6 (UPMC), Laboratoire Leprince-Ringuet (LLR), Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Laboratoire d'Annecy de Physique des Particules (LAPP), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), APC - Astrophysique des Hautes Energies (APC - AHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Dipartimento di Astronomia, Universita degli Studi di Bologna, Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO)-Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), Laboratoire de Physique Théorique et Astroparticules (LPTA), Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), HESS, Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7), PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Annecy de Physique des Particules (LAPP/Laboratoire d'Annecy-le-Vieux de Physique des Particules), Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Dipartimento di Astronomia, Universita degli Studi di Bologna, Università di Bologna [Bologna] (UNIBO)-Università di Bologna [Bologna] (UNIBO)-AstroParticule et Cosmologie (APC (UMR_7164)), and PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris
Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO), Radio galaxy, [SDU.ASTR.CO]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Astrophysics::High Energy Astrophysical Phenomena, Centaurus A, FOS: Physical sciences, Flux, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, Luminosity, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], individual (Cen A) [galaxies], 0103 physical sciences, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Physics, 010308 nuclear & particles physics, Gamma ray, observations [gamma rays], Astronomy and Astrophysics, Cherenkov Telescope Array, Particle acceleration, Crab Nebula, Space and Planetary Science, active [galaxies], Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: We report the discovery of faint very high energy (VHE, E>100 GeV) gamma-ray emission from the radio galaxy Centaurus A in observations performed with the H.E.S.S. experiment, an imaging atmospheric Cherenkov telescope array consisting of four telescopes located in Namibia. Centaurus A has been observed for more than 120 h. A signal with a statistical significance of 5.0 sigma is detected from the region including the radio core and the inner kpc jets. The integral flux above an energy threshold of ~250 GeV is measured to be ~0.8 % of the flux of the Crab Nebula (apparent luminosity: L(>250 GeV)~2.6x10^39 erg s^-1, adopting a distance of 3.8 Mpc. The spectrum can be described by a power law with a photon index of 2.7 +/- 0.5_stat +/- 0.2_sys. No significant flux variability is detected in the data set. However, the low flux only allows detection of variability on the timescale of days to flux increments above a factor of ~15-20 (3 sigma and 4 sigma, respectively). The discovery of VHE gamma-ray emission from Centaurus A reveals particle acceleration in the source to >TeV energies and, together with M 87, establishes radio galaxies as a class of VHE emitters., 5 pages, 4 figures, accepted for publication in ApJ Letters
Published: 2009

37. A search for a dark matter annihilation signal towards the Canis Major overdensity with H.E.S.S

Author: F. Aharonian, A. G. Akhperjanian, U. Barres de Almeida, A. R. Bazer-Bachi, B. Behera, W. Benbow, K. Bernlöhr, C. Boisson, V. Bochow, V. Borrel, I. Braun, E. Brion, J. Brucker, P. Brun, R. Bühler, T. Bulik, I. Büsching, T. Boutelier, S. Carrigan, P. M. Chadwick, A. Charbonnier, R. C. G. Chaves, A. Cheesebrough, L.-M. Chounet, A. C. Clapson, G. Coignet, L. Costamante, M. Dalton, B. Degrange, C. Deil, H. J. Dickinson, A. Djannati-Ataï, W. Domainko, L. O'C. Drury, F. Dubois, G. Dubus, J. Dyks, M. Dyrda, K. Egberts, D. Emmanoulopoulos, P. Espigat, C. Farnier, F. Feinstein, A. Fiasson, A. Förster, G. Fontaine, M. Füssling, S. Gabici, Y. A. Gallant, L. Gérard, B. Giebels, J. F. Glicenstein, B. Glück, P. Goret, C. Hadjichristidis, D. Hauser, M. Hauser, S. Heinz, G. Heinzelmann, G. Henri, G. Hermann, J. A. Hinton, A. Hoffmann, W. Hofmann, M. Holleran, S. Hoppe, D. Horns, A. Jacholkowska, O. C. de Jager, I. Jung, K. Katarzyński, S. Kaufmann, E. Kendziorra, M. Kerschhaggl, D. Khangulyan, B. Khélifi, D. Keogh, Nu. Komin, K. Kosack, G. Lamanna, J.-P. Lenain, T. Lohse, V. Marandon, J. M. Martin, O. Martineau-Huynh, A. Marcowith, D. Maurin, T. J. L. McComb, C. Medina, R. Moderski, E. Moulin, M. Naumann-Godo, M. de Naurois, D. Nedbal, D. Nekrassov, J. Niemiec, S. J. Nolan, S. Ohm, J.-F. Olive, E. de Oña Wilhelmi, K. J. Orford, J. L. Osborne, M. Ostrowski, M. Panter, G. Pedaletti, G. Pelletier, P.-O. Petrucci, S. Pita, G. Pühlhofer, M. Punch, A. Quirrenbach, B. C. Raubenheimer, M. Raue, S. M. Rayner, M. Renaud, F. Rieger, J. Ripken, L. Rob, S. Rosier-Lees, G. Rowell, B. Rudak, C. B. Rulten, J. Ruppel, V. Sahakian, A. Santangelo, R. Schlickeiser, F. M. Schöck, R. Schröder, U. Schwanke, S. Schwarzburg, S. Schwemmer, A. Shalchi, J. L. Skilton, H. Sol, D. Spangler, L. Stawarz, R. Steenkamp, C. Stegmann, G. Superina, P. H. Tam, J.-P. Tavernet, R. Terrier, O. Tibolla, C. van Eldik, G. Vasileiadis, C. Venter, J. P. Vialle, P. Vincent, M. Vivier, H. J. Völk, F. Volpe, S. J. Wagner, M. Ward, A. A. Zdziarski, A. Zech, Centre d'étude spatiale des rayonnements (CESR), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Laboratoire Univers et Théories (LUTH (UMR_8102)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Laboratoire d'Astrophysique de Grenoble (LAOG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Leprince-Ringuet (LLR), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Annecy de Physique des Particules (LAPP/Laboratoire d'Annecy-le-Vieux de Physique des Particules), Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), APC - Astrophysique des Hautes Energies (APC - AHE), Dipartimento di Astronomia, Universita degli Studi di Bologna, Università di Bologna [Bologna] (UNIBO)-Università di Bologna [Bologna] (UNIBO)-AstroParticule et Cosmologie (APC (UMR_7164)), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7), AstroParticule et Cosmologie (APC (UMR_7164)), Laboratoire de Physique Théorique et Astroparticules (LPTA), Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), HESS, Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7), Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Laboratoire d'Annecy de Physique des Particules (LAPP), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Dipartimento di Astronomia, Universita degli Studi di Bologna, Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO)-Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Pierre et Marie Curie - Paris 6 (UPMC), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO)
Subjects: Structure formation, dwarf [galaxies], [SDU.ASTR.CO]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Astrophysics::High Energy Astrophysical Phenomena, Dark matter, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, dark matter, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], WIMP, 0103 physical sciences, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Dwarf galaxy, Physics, Annihilation, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], 010308 nuclear & particles physics, Astrophysics (astro-ph), Order (ring theory), observations [gamma rays], Astronomy and Astrophysics, Space and Planetary Science, Neutralino, Halo
Abstract: A search for a dark matter (DM) annihilation signal into $\gamma$-rays toward the direction of the Canis Major (CMa) overdensity is presented. The nature of CMa is still controversial and one scenario represents it as a dwarf galaxy, making it an interesting candidate for DM annihilation searches. A total of 9.6 hours of high quality data were collected with the H.E.S.S. array of Imaging Atmospheric Cherenkov Telescopes (IACTs) and no evidence for a very high energy $\gamma$-ray signal is found. Upper limits on the CMa dwarf galaxy mass of the order of 10$^{9}$ M$_{\odot}$ are derived at the 95% C.L. assuming neutralino masses in the range 500 GeV - 10 TeV and relatively large annihilation cross-sections. Constraints on the velocity-weighted annihilation cross section $$, are calculated for specific WIMP scenarios, using a NFW model for the DM halo profile and taking advantage of numerical simulations of hierarchical structure formation. 95% C.L. exclusion limits of the order of 5 $\times$ 10$^{-24}$ cm$^{3}$ s$^{-1}$ are reached in the 500 GeV - 10 TeV DM particle mass interval, assuming a total halo mass of 3 $\times$ 10$^{8}$ M$_{\odot}$., Comment: Accepted for publication in ApJ
Published: 2009

38. HESS very-high-energy gamma-ray sources without identified counterparts

Author: F. Aharonian, A. G. Akhperjanian, U. Barres de Almeida, A. R. Bazer-Bachi, B. Behera, M. Beilicke, W. Benbow, K. Bernlöhr, C. Boisson, O. Bolz, V. Borrel, I. Braun, E. Brion, A. M. Brown, R. Bühler, T. Bulik, I. Büsching, T. Boutelier, S. Carrigan, P. M. Chadwick, L.-M. Chounet, A. C. Clapson, G. Coignet, R. Cornils, L. Costamante, M. Dalton, B. Degrange, H. J. Dickinson, A. Djannati-Ataï, W. Domainko, L. O'C. Drury, F. Dubois, G. Dubus, J. Dyks, K. Egberts, D. Emmanoulopoulos, P. Espigat, C. Farnier, F. Feinstein, A. Fiasson, A. Förster, G. Fontaine, S. Funk, M. Füßling, Y. A. Gallant, B. Giebels, J. F. Glicenstein, B. Glück, P. Goret, C. Hadjichristidis, D. Hauser, M. Hauser, G. Heinzelmann, G. Henri, G. Hermann, J. A. Hinton, A. Hoffmann, W. Hofmann, M. Holleran, S. Hoppe, D. Horns, A. Jacholkowska, O. C. de Jager, I. Jung, K. Katarzyński, E. Kendziorra, M. Kerschhaggl, B. Khélifi, D. Keogh, Nu. Komin, K. Kosack, G. Lamanna, I. J. Latham, A. Lemière, M. Lemoine-Goumard, J.-P. Lenain, T. Lohse, J. M. Martin, O. Martineau-Huynh, A. Marcowith, C. Masterson, D. Maurin, G. Maurin, T. J. L. McComb, R. Moderski, E. Moulin, M. de Naurois, D. Nedbal, S. J. Nolan, S. Ohm, J.-P. Olive, E. de Oña Wilhelmi, K. J. Orford, J. L. Osborne, M. Ostrowski, M. Panter, G. Pedaletti, G. Pelletier, P.-O. Petrucci, S. Pita, G. Pühlhofer, M. Punch, S. Ranchon, B. C. Raubenheimer, M. Raue, S. M. Rayner, M. Renaud, J. Ripken, L. Rob, L. Rolland, S. Rosier-Lees, G. Rowell, B. Rudak, J. Ruppel, V. Sahakian, A. Santangelo, R. Schlickeiser, F. Schöck, R. Schröder, U. Schwanke, S. Schwarzburg, S. Schwemmer, A. Shalchi, H. Sol, D. Spangler, Ł. Stawarz, R. Steenkamp, C. Stegmann, G. Superina, P. H. Tam, J.-P. Tavernet, R. Terrier, C. van Eldik, G. Vasileiadis, C. Venter, J. P. Vialle, P. Vincent, M. Vivier, H. J. Völk, F. Volpe, S. J. Wagner, M. Ward, A. A. Zdziarski, A. Zech, Centre d'étude spatiale des rayonnements (CESR), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Laboratoire Univers et Théories (LUTH (UMR_8102)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Département d'Astrophysique, de physique des Particules, de physique Nucléaire et de l'Instrumentation Associée (DAPNIA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Laboratoire d'Astrophysique de Grenoble (LAOG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Leprince-Ringuet (LLR), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Annecy de Physique des Particules (LAPP/Laboratoire d'Annecy-le-Vieux de Physique des Particules), Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), APC - Astrophysique des Hautes Energies (APC - AHE), Dipartimento di Astronomia, Universita degli Studi di Bologna, Università di Bologna [Bologna] (UNIBO)-Università di Bologna [Bologna] (UNIBO)-AstroParticule et Cosmologie (APC (UMR_7164)), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7), AstroParticule et Cosmologie (APC (UMR_7164)), Laboratoire de Physique Théorique et Astroparticules (LPTA), Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), HESS, Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Annecy de Physique des Particules (LAPP), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7), Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Dipartimento di Astronomia, Universita degli Studi di Bologna, Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO)-Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), and Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Pierre et Marie Curie - Paris 6 (UPMC)
Subjects: [SDU.ASTR.CO]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], media_common.quotation_subject, Astrophysics::High Energy Astrophysical Phenomena, Population, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, Spectral line, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], cosmic rays, surveys, 0103 physical sciences, education, 010303 astronomy & astrophysics, Galaxy: general, Cherenkov radiation, general [Galaxy], media_common, Physics, Astrophysical Processes, education.field_of_study, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], 010308 nuclear & particles physics, Gamma ray, observations [gamma rays], Astronomy and Astrophysics, Galactic plane, Galaxy, Space and Planetary Science, Sky, gamma rays: observations
Abstract: Context.The detection of gamma rays in the very-high-energy (VHE) energy range (100 GeV-100 TeV) provides a direct view of the parent population of ultra-relativistic particles found in astrophysical sources. For this reason, VHE gamma rays are useful for understanding the underlying astrophysical processes in non-thermal sources. Aims.We investigate unidentified VHE gamma-ray sources that have been discovered with HESS in the most sensitive blind survey of the Galactic plane at VHE energies conducted so far. Methods.The HESS array of imaging atmospheric Cherenkov telescopes (IACTs) has a high sensitivity compared with previous instruments (~ in 25 h observation time for a point-source detection), and with its large field of view, is well suited for scan-based observations. The on-going HESS survey of the inner Galaxy has revealed a large number of new VHE sources, and for each we attempt to associate the VHE emission with multi-wavelength data in the radio through X-ray wavebands. Results. For each of the eight unidentified VHE sources considered here, we present the energy spectra and sky maps of the sources and their environment. The VHE morphology is compared with available multi-wavelength data (mainly radio and X-rays). No plausible counterparts are found.
Published: 2008

39. Ferroelectric Hafnium Nitride Thin Films Directly Formed on Si(100) Substrate

Author: S. Ohmi, Y. Ohtaguchi, A. Ihara, and H. Morita
Subjects: Hafnium nitride, ferroelectrics, rhombohedral phase, MFS diode, ECR plasma, reactive sputtering, Electrical engineering. Electronics. Nuclear engineering, TK1-9971
Abstract: We have investigated the ferroelectric hafnium nitride (HfN) thin films directly formed on the Si(100) substrate for the metal-ferroelectrics-Si field-effect transistor (MFSFET) applications. The 10 nm thick rhombohedral phase HfN layer was found to be formed on the Si(100) substrate utilizing the post-metallization annealing (PMA) at 400°C/5 min for HfN0.5/HfN1.15/Si(100) MFS diode structure which was deposited with in situ process by the electron cyclotron resonance (ECR) plasma reactive sputtering. The remnant polarization (2Pr) of $24.0 \mu \text{C}$ /cm2 with the coercive field ( ${\text{E}_{c}}$ ) of 3.8 MV/cm was obtained from the P-V characteristic under the voltage sweep of ±10 V. Fatigue characteristics without wake-up were confirmed until 109 program/erase (P/E) cycles under the input pulses of ±6 V/ $5 \mu \text{s}$ although the 2 ${\text {P}_{r}}$ was gradually decreased to $10.7 \mu \text{C}$ /cm2. The polarization (Psw) of $13.4 \mu \text{C}$ /cm2 was clearly observed by the positive-up negative-down (PUND) measurements utilizing the input pulses of ±6 V/ $5 \mu \text{s}$ . The memory window (MW) of 0.32 V was realized in the C-V characteristics by the program operation at −10 V/1 s.
Published: 2021
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40. MUSC information system ARIADNE: a consistent tool for support of experiment planning, execution and scientific evaluation of microgravity-experiments

Author: D. Wilke, D. Padeken, H. Hanz, and S. Ohm
Subjects: Electronic Data Processing, Database, Databases, Factual, Computer science, business.industry, Weightlessness, Control (management), Open design, Aerospace Engineering, Timeline, Modular design, Space Flight, computer.software_genre, Task (computing), Data acquisition, Research Design, Information system, Aerospace Medicine, Database Management Systems, Graphics, business, Software engineering, computer
Abstract: One of the main tasks of DLR-MUSC (Microgravity User Support Center) is to accompany an experiment's complete life-cycle, thus supporting the investigators. This task starts with the preparation of experiments, continues with their execution and finally leads to the evaluation of the respective measurement results. A computer-based information system facilitates these tasks. Considerable effort has been taken in order to make a detailed as well as modular design--as a result the system can now be applied for any mission. ARIADNE mainly supports three phases, all using the same consistent database. 1. The first phase of experiment preparation is supported by--the acquisition and maintenance of general and basic data by user entries into the database, and the support of the integration of partially similar experiment proposals into a timeline as planned which is composed by activities. 2. The support during experiment execution consists of--real-time data acquisition and control (i.e. on-line database generation and display after processing) including experiment monitoring, enabling of fast replanning. 3. The support ARIADNE provides for experiment evaluation includes--the selection of series of measurements belonging to the specified experiment (parts), further processing and evaluation of the collected data, which must partly be done in real-time and partly post-mission and, creation of back-up's of the processing results. The ARIADNE database consists of a relational ORACLE-part (for numerical and character data), a bibliographic part, a program-library, and a realtime-part (BAPAS). The open design of ARIADNE allows interfaces to stored special data (such as graphics, images, archives) as well as several interfaces to other systems, such as CUIS, MARS-MDB, EXPRES, etc.
Published: 1992

41. Ueber eine Interferenz-Erscheinung bei einaxigen Krystallplatten in geradlinig polarisirtem Lichte

Author: G. S. Ohm
Subjects: General Physics and Astronomy
Abstract: n/a
Published: 1852

42. Bemerkungen über Combinationstöne und Stösse

Author: G. S. Ohm
Subjects: Physics, General Physics and Astronomy
Abstract: n/a
Published: 1838

43. Versuch einer Theorie der durch galvanische Kräfte hervorgebrachten elektroskopischen Erscheinungen

Author: G. S. Ohm
Subjects: Physics, General Physics and Astronomy
Published: 1825

44. Versuche über das Tragvermögen hufeisenförmiger Magnete und über die Schwingungsdauer geradliniger Magnetstäbe

Author: Paul Wolfgang Haecker and G. S. Ohm
Subjects: General Physics and Astronomy
Abstract: n/a
Published: 1841

45. Noch ein Paar Worte über die Definition des Tones

Author: G. S. Ohm
Subjects: Philosophy, General Physics and Astronomy
Abstract: n/a
Published: 1843

46. [Group teaching of patients with rheumatoid arthritis]

Author: L, Hjorth, H, Vinterberg, B, Fredriksen, S, Ohm, D, Høgelund, L, Krogsgaard, M, Sejersen, G, Frølich-Møller, I, Cohn, and I, Sonne
Subjects: Adult, Arthritis, Rheumatoid, Male, Adolescent, Patient Education as Topic, Denmark, Humans, Female, Middle Aged, Aged
Published: 1979

47. [Shall the patients just survive?]

Author: L, Fischer and S, Ohm
Subjects: Hospitalization, Legislation, Medical, Health Occupations, Denmark, Economics, Hospital, Legislation, Nursing, Length of Stay, Patient Care Planning
Published: 1974

48. Ueber die Definition des Tones, nebst daran geknüpfter Theorie der Sirene und ähnlicher tonbildender Vorrichtungen

Author: G. S. Ohm
Subjects: Computer science, General Physics and Astronomy
Abstract: n/a
Published: 1842

49. Beschreibung einiger einfachen und leicht zu behandelnden Vorrichtungen zur Anstellung der Licht-Interferenz-Versuche

Author: G. S. Ohm
Subjects: General Physics and Astronomy
Abstract: n/a
Published: 1839

50. Ultrafast Dynamics of a Nucleobase Analogue Illuminated by a Short Intense X-ray Free Electron Laser Pulse

Author: K. Nagaya, K. Motomura, E. Kukk, H. Fukuzawa, S. Wada, T. Tachibana, Y. Ito, S. Mondal, T. Sakai, K. Matsunami, R. Koga, S. Ohmura, Y. Takahashi, M. Kanno, A. Rudenko, C. Nicolas, X.-J. Liu, Y. Zhang, J. Chen, M. Anand, Y. H. Jiang, D.-E. Kim, K. Tono, M. Yabashi, H. Kono, C. Miron, M. Yao, and K. Ueda
Subjects: Physics, QC1-999
Abstract: Understanding x-ray radiation damage is a crucial issue for both medical applications of x rays and x-ray free-electron-laser (XFEL) science aimed at molecular imaging. Decrypting the charge and fragmentation dynamics of nucleobases, the smallest units of a macro-biomolecule, contributes to a bottom-up understanding of the damage via cascades of phenomena following x-ray exposure. We investigate experimentally and by numerical simulations the ultrafast radiation damage induced on a nucleobase analogue (5-iodouracil) by an ultrashort (10 fs) high-intensity radiation pulse generated by XFEL at SPring-8 Angstrom Compact free electron Laser (SACLA). The present study elucidates a plausible underlying radiosensitizing mechanism of 5-iodouracil. This mechanism is independent of the exact composition of 5-iodouracil and thus relevant to other such radiosensitizers. Furthermore, we found that despite a rapid increase of the net molecular charge in the presence of iodine, and of the ultrafast release of hydrogen, the other atoms are almost frozen within the 10-fs duration of the exposure. This validates single-shot molecular imaging as a consistent approach, provided the radiation pulse used is brief enough.
Published: 2016
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