Author: "Ohm, Stefan" / Publication Year Range: Last 10 years - Searchworks@Jio Institute Digital Library Search Results

Your search keyword '"Ohm, Stefan"' showing total 108 results

Start Over Author "Ohm, Stefan" Publication Year Range Last 10 years

108 results on '"Ohm, Stefan"'

1. Probing VHE gamma-ray emission from GW events with H.E.S.S

Author: Ashkar, Halim, de Lavergne, Mathieu de Bony, Brun, Francois, Fegan, Stephen, Konno, Ruslan, Ohm, Stefan, Prokoph, Heike, Schüssler, Fabian, and Zhu, Sylvia J
Subjects: Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Instrumentation and Methods for Astrophysics
Abstract: Gravitational wave (GW) events, particularly those connected to the merger of compact objects such as neutron stars, are believed to be the primary source of short gamma-ray bursts. To explore the very high energy (VHE) component of the emission from these events, the H.E.S.S. collaboration has dedicated a substantial effort and observing time to follow up on these events. During the second and third GW observing runs, H.E.S.S. was the first ground-based instrument to observe the GW170817 binary neutron star merger. In addition, H.E.S.S. followed four binary black hole mergers. The data acquired by H.E.S.S. was used to constrain the VHE emission from these events for the first time. H.E.S.S. also monitored the GW170817 source for approximately 50 hours and obtained limits that constrained the magnetic field in the merger remnant to $> 24 \mu G$. As the fourth GW observing run (O4) approaches, the H.E.S.S. collaboration has allocated significant observation time to the follow-up of GW events. This contribution provides an overview of the science results derived from the H.E.S.S. follow-up of GW events, a technical overview of the GW follow-up strategies for O4, and an update on H.E.S.S. activities during O4., Comment: Proceedings 38th International Cosmic Ray Conference (ICRC2023)
Published: 2023

2. Validating Monte Carlo simulations for an analysis chain in H.E.S.S

Author: Leuschner, Fabian, Schäfer, Johannes, Steinmassl, Simon, Holch, Tim Lukas, Bernlöhr, Konrad, Funk, Stefan, Hinton, Jim, Ohm, Stefan, and Pühlhofer, Gerd
Subjects: Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - High Energy Astrophysical Phenomena
Abstract: Imaging Air Cherenkov Telescopes (IACTs) detect very high energetic (VHE) gamma rays. They observe the Cherenkov light emitted in electromagnetic shower cascades that gamma rays induce in the atmosphere. A precise reconstruction of the primary photon energy and the source flux depends heavily on accurate Monte Carlo (MC) simulations of the shower propagation and the detector response, and therefore also on adequate assumptions about the atmosphere at the site and time of a measurement. Here, we present the results of an extensive validation of the MC simulations for an analysis chain of the H.E.S.S. experiment with special focus on the recently installed FlashCam camera on the large 28 m telescope. One goal of this work was to create a flexible and easy-to-use framework to facilitate the detailed validation of MC simulations also for past and future phases of the H.E.S.S. experiment. Guided by the underlying physics, the detector simulation and the atmospheric transmission profiles were gradually improved until low level parameters such as cosmic ray (CR) trigger rates matched within a few percent between simulations and observational data. This led to instrument response functions (IRFs) with which the analysis of current H.E.S.S. data can ultimately be carried out within percent accuracy, substantially improving earlier simulations., Comment: 8 pages, 4 figures, 1 table. Accepted as Proceeding of the 7th Heidelberg International Symposium on High-Energy Gamma-Ray Astronomy (Gamma2022)
Published: 2023
Full Text: View/download PDF

3. Analysis optimisation for more than 10 TeV gamma-ray astronomy with IACTs

Author: Lypova, Iryna, Berge, David, Klepser, Stefan, Kostunin, Dmitriy, Ohm, Stefan, and Wagner, Stefan
Subjects: Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - High Energy Astrophysical Phenomena
Abstract: The High Energy Stereoscopic System (H.E.S.S.) is one of the currently operating Imaging Atmospheric Cherenkov Telescopes. H.E.S.S. operates in the broad energy range from a few tens of GeV to more than 50 TeV reaching its best sensitivity around 1 TeV. In this contribution, we present an analysis technique, which is optimised for the detection at the highest energies accessible to H.E.S.S. and aimed to improve the sensitivity above 10 TeV. It includes the employment of improved event direction reconstruction and gamma-hadron separation. For the first time, also extensive air showers with event offsets up to 4.5$^{\circ}$ from the camera centre are considered in the analysis, thereby increasing the effective Field-of-View of H.E.S.S. from 5$^{\circ}$ to 9$^{\circ}$. Key performance parameters of the new high-energy analysis are presented and its applicability demonstrated for representative hard-spectrum sources in the Milky Way., Comment: Proceedings of the 37th International Cosmic Ray Conference (ICRC2021)
Published: 2021

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

Author: Ashkar, Halim, Brun, Francois, Füßling, Matthias, Hoischen, Clemens, Konno, Ruslan, Ohm, Stefan, Prokoph, Heike, Reichherzer, Patrick, Schüssler, Fabian, Arroyo, Monica Seglar, and Zhu, Sylvia J
Subjects: Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - High Energy Astrophysical Phenomena
Abstract: 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., Comment: Proceedings of the 37th International Cosmic Ray Conference (ICRC2021), 12-23 July 2021, Berlin, Germany - Online
Published: 2021
Full Text: View/download PDF

5. The young massive stellar cluster Westerlund 1 in $\gamma$ rays as seen with H.E.S.S

Author: Mohrmann, Lars, Specovius, Andreas, Rauth, Romed, Ohm, Stefan, and van Eldik, Christopher
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: Massive stellar clusters have recently been hypothesised as candidates for the acceleration of hadronic cosmic rays up to PeV energies. Previously, the H.E.S.S. Collaboration has reported about very extended $\gamma$-ray emission around Westerlund 1, a massive young stellar cluster in the Milky Way. In this contribution we present an updated analysis that employs a new analysis technique and is based on a much larger data set, allowing us to constrain better the morphology and the energy spectrum of the emission. The analysis technique used is a three-dimensional likelihood analysis, which is especially well suited for largely extended sources. The origin of the $\gamma$-ray emission will be discussed in light of multi-wavelength observations., Comment: 10 pages, 6 figures, ICRC 2021 conference proceedings
Published: 2021
Full Text: View/download PDF

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

Author: Zhu, Sylvia J., Holch, Tim Lukas, Murach, Thomas, Ohm, Stefan, Fuessling, Matthias, de Naurois, Mathieu, Krack, Fabian, Mosshammer, Klemens, and Lindemann, Rico
Subjects: Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - High Energy Astrophysical Phenomena
Abstract: 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., Comment: Proceedings of the 37th International Cosmic Ray Conference (ICRC2021)
Published: 2021

7. H.E.S.S. follow-up of BBH merger events

Author: Ashkar, Halim, Brun, Francois, Hoischen, Clemens, Konno, Ruslan, Ohm, Stefan, Prokoph, Heike, Schüssler, Fabian, Arroyo, Monica Seglar, and Zhu, Sylvia J
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: We present here, follow-up observations of four Binary black hole BBH events performed with the High Energy Stereoscopic System (H.E.S.S.) in the Very High Energy (VHE) gamma-ray domain during the second and third LIGO/Virgo observation runs. Detailed analyses of the obtained data did not show significant VHE emission. We derive integral upper limit maps considering a generic $E^{-2}$ source spectrum in the most sensitive H.E.S.S energy interval ranging from 1 to 10 TeV. We also consider Extragalactic Background Light absorption effects and derive integral upper limits over the full accessible energy range. We finally derive upper limits of the VHE luminosity for each event and compare them with the expected VHE emission from GRBs. These comparisons allow us to assess the H.E.S.S. gravitational wave follow-up strategies. For the fourth GW observing run O4, we do not expect to fundamentally alter our observing strategy, and will continue to prioritize sky coverage like for the previous runs, Comment: Proceedings of the 37th International Cosmic Ray Conference (ICRC2021), 12-23 July 2021, Berlin, Germany - Online
Published: 2021
Full Text: View/download PDF

8. Making cosmic particle accelerators visible and audible

Author: Ohm, Stefan, Rappaport, Konrad, Nicolai, Carsten, Mundzeck, Till, Taylor, Andrew, Zhu, Sylvia Jiechen, Füßling, Matthias, and Parsons, Robert Daniel
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: 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., Comment: Presented at the 37th International Cosmic Ray Conference (ICRC 2021)
Published: 2021

9. Deep observations of Kepler's SNR with H.E.S.S

Author: Prokhorov, Dmitry, Vink, Jacco, Simoni, Rachel, Komin, Nukri, Funk, Stefan, Malyshev, Denys, Mohrmann, Lars, Ohm, Stefan, Pühlhofer, Gerd, and Völk, Heinrich J.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: Kepler's supernova remnant (SNR) which is produced by the most recent naked-eye supernova in our Galaxy is one of the best studied SNRs, but its gamma-ray detection has eluded us so far. Observations with modern imaging atmospheric Cherenkov telescopes (IACT) have enlarged the knowledge about nearby SNRs with ages younger than 500 years by establishing Cassiopeia A and Tycho's SNRs as very high energy (VHE) gamma-ray sources and setting a lower limit on the distance to Kepler's SNR. This SNR is significantly more distant than the other two and expected to be one of the faintest gamma-ray sources within reach of the IACT arrays of this generation. We report strong evidence for a VHE signal from Kepler's SNR based on deep observations of the High Energy Stereoscopic System (H.E.S.S.) with an exposure of 152 hours, including 122 hours accumulated in 2017-2020. We further discuss implications of this result for cosmic-ray acceleration in young SNRs., Comment: Proceedings of the 37th International Cosmic Ray Conference (ICRC 2021)
Published: 2021

10. The H.E.S.S. Gravitational Wave Rapid Follow-up Program

Author: Ashkar, Halim, Brun, Francois, Füßling, Matthias, Hoischen, Clemens, Ohm, Stefan, Prokoph, Heike, Reichherzer, Patrick, Schüssler, Fabian, and Seglar-Arroyo, Monica
Subjects: Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Instrumentation and Methods for Astrophysics
Abstract: Gravitational Wave (GW) events are physical processes that significantly perturbate space-time, e.g. compact binary coalescenses, causing the production of GWs. The detection of GWs by a worldwide network of advanced interferometers offer unique opportunities for multi-messenger searches and electromagnetic counterpart associations. While carrying extremely useful information, searches for associated electromagnetic emission are challenging due to large sky localisation uncertainties provided by the current GW observatories LIGO and Virgo. Here we present the methods and procedures used within the High Energy Stereoscopic System (H.E.S.S.) in searches for very-high-energy (VHE) gamma-ray emission associated to the emission of GWs from extreme events. To do so we create several algorithms dedicated to schedule GW follow-up observations by creating optimized pointing paterns. We describe algorithms using 2-dimensional GW localisation information and algorithms correlating the galaxy distribution in the local universe, by using galaxy catalogs, with the 3-dimensional GW localisation information and evaluate their performances. The H.E.S.S. automatic GW follow-up chain, described in this paper, is optimized to initiate GW follow-up observations within less than 1 minute after the alert reception. These developements allowed H.E.S.S. observations of 6 GW events out of the 67 non-retracted GW events detected during the first three observation runs of LIGO and Virgo reaching VHE $\gamma$-ray coverages of up to 70% of the GW localisation., Comment: 27 pages, 15 figures
Published: 2020
Full Text: View/download PDF

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

Author: Ashton, Terry, Backes, Michael, Balzer, Arnim, Berge, David, Bolmont, Julien, Bonnefoy, Simon, Brun, Francois, Chaminade, Thomas, Delagnes, Eric, Fontaine, Gerard, Füßling, Matthias, Giavitto, Gianluca, Giebels, Berrie, Glicenstein, Jean-Francois, Gräber, Tobias, Hinton, Jim, Jahnke, Albert, Klepser, Stefan, Kossatz, Marko, Kretzschmann, Axel, Lefranc, Valentin, Leich, Holger, Lenain, Jean-Philippe, Lüdecke, Hartmut, Lypova, Iryna, Manigot, Pascal, Marandon, Vincent, Moulin, Emmanuel, Murach, Thomas, de Naurois, Mathieu, Nayman, Patrick, Ohm, Stefan, Penno, Marek, Ross, Duncan, Salek, David, Schade, Markus, Schwab, Thomas, Shiningayamwe, Kleopas, Stegmann, Christian, Steppa, Constantin, Tavernet, Jean-Paul, Thornhill, Julian, Toussnel, Francois, and Vincent, Pascal
Subjects: Astrophysics - Instrumentation and Methods for Astrophysics
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
Full Text: View/download PDF

12. Current status and operation of the H.E.S.S. array of imaging atmospheric Cherenkov telescopes

Author: Ohm, Stefan and Wagner, Stefan
Published: 2023
Full Text: View/download PDF

13. H.E.S.S. searches for TeV gamma rays associated to high-energy neutrinos

Author: Schüssler, Fabian, Ashkar, Halim, Backes, Michael, Egberts, Kathrin, Brun, Francois, Füßling, Matthias, Hoischen, Clemens, Lenain, Jean-Philippe, Lypova, Iryna, Ohm, Stefan, Parsons, Dan, Romoli, Carlo, Seglar-Arroyo, Monica, Zacharias, Michael, and Zech, Andreas
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: The detection of an astrophysical flux of high-energy neutrinos by IceCube is a major step forward in the search for the origin of cosmic rays, as this emission is expected to originate in hadronic interactions taking place in or near cosmic-ray accelerators. No neutrino point sources, or significant correlation with known astrophysical objects, have been identified in the IceCube data so far. The hadronic interactions responsible for the neutrino emission should also lead to the production of high-energy gamma rays. The search for neutrino sources can then be performed by studying the spatial and temporal correlations between neutrino events and very high energy (VHE, E > 100 GeV) gamma rays. We report here on the search for VHE gamma-ray emission with the H.E.S.S. imaging air Cherenkov telescopes (IACTs) at the reconstructed position of muon neutrino events detected by IceCube. We will provide an up-to-date summary of the extensive program to perform prompt IACT observations of realtime IceCube neutrino event positions. A recent highlight of this program are the H.E.S.S. observations during the broad multi-wavelength campaign that followed the detection of the neutrino event IceCube-170922A arriving from a direction consistent with the location of a flaring gamma-ray blazar TXS 0506+056 in September 2017. We'll present the H.E.S.S. observations obtained within ~4h hours of the neutrino detection as well as a complementary search for gamma-ray emission at longer timescales and put them into the multi-wavelength and multi-messenger context., Comment: Proceedings of the 36th International Cosmic Ray Conference, 2019, Madison, WI, USA
Published: 2019

14. Searches for counterparts of gravitational waves at very high energies with H.E.S.S

Author: Seglar-Arroyo, Monica, Ashkar, Halim, Bonnefoy, Simon, Brun, Francois, Egberts, Kathrin, Füßling, Matthias, Hoischen, Clemens, Murach, Thomas, Ohm, Stefan, Pühlhofer, Gerd, Rowell, Gavin, Schüssler, Fabian, and Taylor, Andrew
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: The recent milestones in multi-messenger astronomy have opened new ways to study the Unverse. The unprecedented gravitational wave (GW) follow-up campaigns established the power that the combination of different messengers has to identify and study the nature and evolution of astrophysical phenomena. Here we focus on the search for high-energy gamma ray emission as electromagnetic counterpart of compact binary coalescences with the H.E.S.S. Imaging Air Cherenkov Telescopes (IACTs). In this contribution, the optimized strategies developed specifically for the prompt follow-up of gravitational wave events with H.E.S.S are presented. As illustration, the successful observation campaigns up to this time will be described, including the ones during Observation Run O2 on the binary black hole (BH-BH) merger GW170814 and the binary neutron star (NS-NS) merger GW170817, and an update on recent events occurring during O3. Results of these searches are presented and the constraints that prompt observations can put on very-high-energy, non-thermal emission, are briefly discussed. Finally, an outlook on further improvements for the gravitational waves follow-up program with H.E.S.S. will be provided.
Published: 2019

15. Magnetic field estimates from the X-ray synchrotron emitting rims of the 30 Dor C superbubble and the implications for the nature of 30 Dor C's TeV emission

Author: Kavanagh, Patrick J., Vink, Jacco, Sasaki, Manami, Chu, You-Hua, Filipovic, Miroslav D., Ohm, Stefan, Haberl, Frank, Manojlovic, Perica, and Maggi, Pierre
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: The 30 Dor C superbubble is unique for its synchrotron X-ray shell, as well as being the first superbubble to be detected in TeV $\gamma$-rays, though the dominant TeV emission mechanism, i.e., leptonic or hadronic, is still unclear. We aim to use new Chandra observations of 30 Dor C to resolve the synchrotron shell in unprecedented detail and to estimate the magnetic ($B$) field in the postshock region, a key discriminator between TeV $\gamma$-ray emission mechanisms. We extracted radial profiles in the 1.5-8 keV range from various sectors around the synchrotron shell and fitted these with a projected and point spread function convolved postshock volumetric emissivity model to determine the filament widths. We then calculated the postshock magnetic field strength from these widths. We found that most of the sectors were well fitted with our postshock model and the determined $B$-field values were low, all with best fits $\lesssim 20~\mu$G. Upper limits on the confidence intervals of three sectors reached $\gtrsim 30~\mu$G though these were poorly constrained. The generally low $B$-field values suggests a leptonic-dominated origin for the TeV $\gamma$-rays. Our postshock model did not provide adequate fits to two sectors. We found that one sector simply did not provide a clean enough radial profile, while the other could be fitted with a modified model where the projected profile falls off abruptly below $\sim0.8$ times the shell radius, yielding a postshock $B$-field of 4.8 (3.7-11.8) $\mu$G which is again consistent with the leptonic TeV $\gamma$-ray mechanism. Alternatively, the observed profiles in these sectors could result from enhancements around a shock-cloud interaction as suggested in previous works. The average $B$-field determined around the X-ray synchrotron shell of 30 Dor C suggests the leptonic scenario as the dominant emission mechanism for the TeV $\gamma$-rays., Comment: 16 pages, 14 figures, accepted for publication in Astronomy & Astrophysics
Published: 2018
Full Text: View/download PDF

16. On the expected $\gamma$-ray emission from nearby flaring stars

Author: Ohm, Stefan and Hoischen, Clemens
Subjects: Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Solar and Stellar Astrophysics
Abstract: Stellar flares have been extensively studied in soft X-rays (SXR) by basically every X-ray mission. Hard X-ray (HXR) emission from stellar superflares, however, have only been detected from a handful of objects over the past years. One very extreme event was the superflare from the young M-dwarf DG CVn binary star system, which triggered Swift/BAT as if it was a $\gamma$-ray burst (GRB). In this work, we estimate the expected $\gamma$-ray emission from DG CVn and the most extreme stellar flares by extrapolating from solar flares based on measured solar energetic particles (SEPs), as well as thermal and non-thermal emission properties. We find that ions are plausibly accelerated in stellar superflares to 100 GeV energies, and possibly up to TeV energies in the associated coronal mass ejections. The corresponding $\pi^0$-decay $\gamma$-ray emission could be detectable from stellar superflares with ground-based $\gamma$-ray telescopes. On the other hand, the detection of $\gamma$-ray emission implies particle densities high enough that ions suffer significant losses due to inelastic proton-proton scattering. The next-generation Cherenkov Telescope Array (CTA) should be able to probe superflares from M-dwarfs in the solar neighbourhood and constrain the energy in interacting cosmic rays and/or their maximum energy. The detection of $\gamma$-ray emission from stellar flares would open a new window for the study of stellar physics, the underlying physical processes in flares and their impact on habitability of planetary systems., Comment: 8 pages, 3 figures, 2 tables
Published: 2017
Full Text: View/download PDF

17. Starburst galaxies as seen by gamma-ray telescopes

Author: Ohm, Stefan
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: Starburst galaxies have a highly increased star-formation rate compared to regular galaxies and inject huge amounts of kinetic power into the interstellar medium via supersonic stellar winds, and supernova explosions. Supernova remnants, which are considered to be the main source of cosmic rays (CRs), form an additional, significant energy and pressure component and might influence the star-formation process in a major way. Observations of starburst galaxies at \gamma-ray energies gives us the unique opportunity to study non-thermal phenomena associated with hadronic CRs and their relation to the star-formation process. In this work, recent observations of starburst galaxies with space and ground-based \gamma-ray telescopes are being reviewed and the current state of theoretical work on the \gamma-ray emission is discussed. A special emphasis is put on the prospects of the next-generation Cherenkov Telescope Array for the study of starburst galaxies in particular and star-forming galaxies in general., Comment: 10 pages, 3 figures. To be published in a topical review of Comptes Rendus Physique on "Gamma-ray Astronomy", Eds. B. Degrange & G. Fontaine
Published: 2016
Full Text: View/download PDF

18. The On-Site Analysis of the Cherenkov Telescope Array

Author: Bulgarelli, Andrea, Fioretti, Valentina, Zoli, Andrea, Aboudan, Alessio, Rodríguez-Vázquez, Juan José, De Cesare, Giovanni, De Rosa, Adriano, Maier, Gernot, Lyard, Etienne, Bastieri, Denis, Lombardi, Saverio, Tosti, Gino, Bergamaschi, Sonia, Beneventano, Domenico, Lamanna, Giovanni, Jacquemier, Jean, Kosack, Karl, Antonelli, Lucio Angelo, Boisson, Catherine, Borkowski, Jerzy, Buson, Sara, Carosi, Alessandro, Conforti, Vito, Colomé, Pep, Reyes, Raquel de los, Dumm, Jon, Evans, Phil, Fortson, Lucy, Fuessling, Matthias, Gotz, Diego, Graciani, Ricardo, Gianotti, Fulvio, Grandi, Paola, Hinton, Jim, Humensky, Brian, Inoue, Susumu, Knödlseder, Jürgen, Flour, Thierry Le, Lindemann, Rico, Malaguti, Giuseppe, Markoff, Sera, Marisaldi, Martino, Neyroud, Nadine, Nicastro, Luciano, Ohm, Stefan, Osborne, Julian, Oya, Igor, Rodriguez, Jerome, Rosen, Simon, Ribo, Marc, Tacchini, Alessandro, Schüssler, Fabian, Stolarczyk, Thierry, Torresi, Eleonora, Testa, Vincenzo, Wegner, Peter, and Weinstein, Amanda
Subjects: Astrophysics - Instrumentation and Methods for Astrophysics
Abstract: The Cherenkov Telescope Array (CTA) observatory will be one of the largest ground-based very high-energy gamma-ray observatories. The On-Site Analysis will be the first CTA scientific analysis of data acquired from the array of telescopes, in both northern and southern sites. The On-Site Analysis will have two pipelines: the Level-A pipeline (also known as Real-Time Analysis, RTA) and the level-B one. The RTA performs data quality monitoring and must be able to issue automated alerts on variable and transient astrophysical sources within 30 seconds from the last acquired Cherenkov event that contributes to the alert, with a sensitivity not worse than the one achieved by the final pipeline by more than a factor of 3. The Level-B Analysis has a better sensitivity (not be worse than the final one by a factor of 2) and the results should be available within 10 hours from the acquisition of the data: for this reason this analysis could be performed at the end of an observation or next morning. The latency (in particular for the RTA) and the sensitivity requirements are challenging because of the large data rate, a few GByte/s. The remote connection to the CTA candidate site with a rather limited network bandwidth makes the issue of the exported data size extremely critical and prevents any kind of processing in real-time of the data outside the site of the telescopes. For these reasons the analysis will be performed on-site with infrastructures co-located with the telescopes, with limited electrical power availability and with a reduced possibility of human intervention. This means, for example, that the on-site hardware infrastructure should have low-power consumption. A substantial effort towards the optimization of high-throughput computing service is envisioned to provide hardware and software solutions with high-throughput, low-power consumption at a low-cost., Comment: In Proceedings of the 34th International Cosmic Ray Conference (ICRC2015), The Hague, The Netherlands. All CTA contributions at arXiv:1508.05894
Published: 2015

19. The upgrade of the H.E.S.S. cameras

Author: Giavitto, Gianluca, Ashton, Terry, Balzer, Arnim, Berge, David, Brun, Francois, Chaminade, Thomas, Delagnes, Eric, Fontaine, Gerard, Füßling, Matthias, Giebels, Berrie, Glicenstein, Jean-Francois, Gräber, Tobias, Hinton, Jim, Jahnke, Albert, Klepser, Stefan, Kossatz, Marko, Kretzschmann, Axel, Lefranc, Valentin, Leich, Holger, Lüdecke, Hartmut, Lypova, Iryna, Manigot, Pascal, Marandon, Vincent, Moulin, Emmanuel, Naurois, Mathieu de, Nayman, Patrick, Ohm, Stefan, Penno, Marek, Ross, Duncan, Salek, David, Schade, Markus, Schwab, Thomas, Simoni, Rachel, Stegmann, Christian, Steppa, Constantin, Thornhill, Julian, and Toussnel, Francois
Published: 2017
Full Text: View/download PDF

20. The Eta Carinae 2020 periastron passage as seen by H.E.S.S.

Author: Steinmassl, Simon, primary, Marandon, Vincent, additional, Remy, Quentin, additional, Hinton, Jim, additional, Collaboration, H.E.S.S., additional, Aharonian, Felix, additional, Ait-Benkhali, Faical, additional, Alkan, Attila, additional, Aschersleben, Jann, additional, Ashkar, Halim, additional, Backes, Michael, additional, Baktash, Ali, additional, Barbosa Martins, Victor, additional, Barnacka, Anna, additional, Barnard, Joleen, additional, Batzofin, Rowan William, additional, Becherini, Yvonne, additional, Beck, Geoffrey, additional, Berge, David, additional, Bernloehr, Konrad, additional, Bi, Baiyang, additional, Boettcher, Markus, additional, Boisson, Catherine, additional, Bolmont, Julien, additional, Bony (de), Mathieu, additional, Borowska, Jowita, additional, Bouyahiaoui, Makarim, additional, Bradascio, Federica, additional, Breuhaus, Mischa, additional, Brose, Robert, additional, Brown, Anthony, additional, Brun, Francois, additional, Bruno, Benedetta, additional, Bulik, Tomasz, additional, Burger-Scheidlin, Christopher, additional, Bylund, Thomas, additional, Cangemi, Floriane, additional, Caroff, Sami, additional, Casanova, Sabrina, additional, Cecil, Rahul, additional, Celic, Jelena, additional, Cerruti, Matteo, additional, Chambéry, Pauline, additional, Chand, Tej Bahadur, additional, Chandra, Sunil, additional, Chen, Andrew, additional, Chibueze, James Okwe, additional, Chibueze, Ogochukwu, additional, Collins, Tiffany, additional, Cotter, Garret, additional, Cristofari, Pierre, additional, Damascene Mbarubucyeye, Jean, additional, Davids, Isak Delberth, additional, Davies, James, additional, de Jonge, Laenita, additional, Devin, Justine, additional, Djannati-Ataï, Arache, additional, Djuvsland, Julia Isabel, additional, Dmytriiev, Anton, additional, Doroshenko, Victor, additional, Dreyer, Lente, additional, Du Plessis, Louis, additional, Egberts, Kathrin, additional, Einecke, Sabrina, additional, ERNENWEIN, Jean-Pierre, additional, Fegan, Steven, additional, Feijen, Kirsty, additional, Fichet de Clairfontaine, Gaëtan, additional, Fontaine, Gerard, additional, Frans, Lott, additional, Fuessling, Matthias, additional, Funk, Stefan, additional, Gabici, Stefano, additional, Gallant, Yves, additional, Ghafourizadeh, Shahede, additional, Giavitto, Gianluca, additional, Giunti, Luca, additional, Glawion, Dorit, additional, Glicenstein, Jean-Francois, additional, Glombitza, Jonas, additional, Goswami, Pranjupriya, additional, Grolleron, Guillaume, additional, Grondin, Marie-Hélène, additional, Haerer, Lucia, additional, Hattingh, Sumari, additional, Haupt, Maria, additional, HERMANN, German, additional, Hofmann, Werner, additional, Holch, Tim, additional, Holler, Markus, additional, Horns, Dieter, additional, Huang, Zhiqiu, additional, Jaitly, Annanay, additional, Jamrozy, Marek, additional, Jankowsky, Felix, additional, Jardin-Blicq, Armelle, additional, Joshi, Vikas, additional, Jung-Richardt, Ira, additional, Kasai, Eli, additional, Katarzynski, Krzysztof, additional, Katjaita, Hiiko, additional, Khangulyan, Dmitry, additional, Khatoon, Rukaiya, additional, Khelifi, Bruno, additional, Klepser, Stefan, additional, Kluzniak, Wlodek, additional, Komin, Nukri, additional, Konno, Ruslan, additional, Kosack, Karl, additional, Kostunin, Dmitriy, additional, Kundu, Anu, additional, Lamanna, Giovanni, additional, Lang, Rodrigo Guedes, additional, Le Stum, Sebastien, additional, Lefranc, Valentin, additional, Leitl, Franziska, additional, Lemiere, Anne, additional, Lemoine-Goumard, Marianne, additional, Lenain, Jean-Philippe, additional, Leuschner, Fabian, additional, Luashvili, Anna, additional, Lypova, Iryna, additional, Mackey, Jonathan, additional, Malyshev, Denys, additional, Malyshev, Dmitry, additional, Marcowith, Alexandre, additional, Marinos, Peter David, additional, Marti'i-Devesa, Guillem, additional, Marx, Ramin, additional, Maurin, Gilles, additional, Mehta, Abhay, additional, Meintjes, Pieter, additional, Meyer, Manuel, additional, Mitchell, Alison, additional, Moderski, Rafal, additional, Mohrmann, Lars, additional, Montanari, Alessandro, additional, Moore, Chris, additional, Moulin, Emmanuel, additional, Murach, Thomas, additional, Nakashima, Kaori, additional, Naurois (de), Mathieu, additional, Ndiyavala, Hambeleleni, additional, Niemiec, Jacek, additional, Noel, Angel, additional, O'Brien, Paul, additional, Ohm, Stefan, additional, Olivera-Nieto, Laura, additional, Ona-Wilhelmi (de), Emma, additional, Ostrowski, Michal, additional, Oukacha, Enzo, additional, Panny, Sebastian, additional, Panter, Michael, additional, Parsons, Dan, additional, Pensec, Ugo, additional, Peron, Giada, additional, Pita, Santiago, additional, Poireau, Vincent, additional, Prokhorov, Dmitry, additional, Prokoph, Heike, additional, PUEHLHOFER, Gerd, additional, Punch, Michael, additional, Quirrenbach, Andreas, additional, Regeard, Maxime, additional, Reichherzer, Patrick, additional, Reimer, Anita, additional, Reimer, Olaf, additional, Reis, Igor, additional, Ren, Helena X., additional, Renaud, Matthieu, additional, Reville, Brian, additional, Rieger, Frank, additional, Roellinghoff, Gerrit, additional, Rol, Evert, additional, Rowell, Gavin P, additional, Rudak, Bronislaw, additional, Rueda Ricarte, Hector, additional, Ruiz Velasco, Edna, additional, Sabri, Karim, additional, Sahakian, Vardan, additional, Sailer, Simon, additional, Salzmann, Heiko, additional, Sanchez, David, additional, Santangelo, Andrea, additional, Sasaki, Manami, additional, Schaefer, Johannes, additional, Schuessler, Fabian, additional, Schutte, Hester, additional, Senniappan, Mohanraj, additional, Shapopi, Jimmy N.S., additional, Shilunga, Sigrid, additional, Shiningayamwe, Kleopas, additional, Sol, Helene, additional, Spackman, Hugh, additional, Specovius, Andreas, additional, Spencer, Samuel, additional, Stawarz, Lukasz, additional, Steenkamp, Riaan, additional, Stegmann, Christian, additional, Steppa, Constantin, additional, Streil, Katrin, additional, Sushch, Iurii, additional, Suzuki, Hiromasa, additional, Takahashi, Tadayuki, additional, Tanaka, Takaaki, additional, Tavernier, Thomas, additional, Taylor, Andrew, additional, Terrier, Regis, additional, Thakur, Adnaan, additional, Thiersen, Hannes, additional, Thorpe-Morgan, Charles, additional, Tluczykont, Martin, additional, Tsirou, Michelle, additional, Tsuji, Naomi, additional, Tuffs, Richard, additional, Uchiyama, Yasunobu, additional, Ullmo, Marion, additional, Unbehaun, Tim, additional, van der Merwe, Pieter, additional, van Eldik, Christopher, additional, van Soelen, Brian, additional, Vasileiadis, George, additional, Vecchi, Manuela, additional, Veh, Johannes, additional, Venter, Christo, additional, Vink, Jacco, additional, Voelk, Heinrich, additional, Vogel, Naomi, additional, Wach, Tina, additional, Wagner, Stefan, additional, Werner, Felix, additional, White, Richard, additional, Wierzcholska, Alicja, additional, Wong, Yu Wun, additional, Yassin, Hend Mahmoud, additional, Zacharias, Michael, additional, Zargaryan, Davit, additional, Zdziarski, Andrzej, additional, Zech, Andreas, additional, Zhu, Sylvia, additional, Zmija, Andreas, additional, Zouari, Samuel, additional, and Żywucka, Natalia, additional
Published: 2023
Full Text: View/download PDF

21. Probing VHE gamma-ray emission from GW events with H.E.S.S.

Author: Ashkar, Halim, primary, Brun, Francois, additional, Fegan, Stephen, additional, Konno, Ruslan, additional, Ohm, Stefan, additional, Prokoph, Heike, additional, Schüssler, Fabian, additional, and Zhu, Sylvia, additional
Published: 2023
Full Text: View/download PDF

22. Validation of Monte Carlo Simulations for an analysis chain in H.E.S.S.

Author: Leuschner, Fabian, primary, Schäfer, Johannes, additional, Steinmassl, Simon, additional, Holch, Tim Lukas, additional, Bernlöhr, Konrad, additional, Funk, Stefan, additional, Hinton, Jim, additional, Ohm, Stefan, additional, and Pühlhofer, Gerd, additional
Published: 2023
Full Text: View/download PDF

23. Search for VHE gamma-ray emission from the TDE candidate AT 2021uqv with H.E.S.S.

Author: Lypova, Iryna, primary, Ashkar, Halim, additional, Konno, Ruslan, additional, Kostunin, Dmitriy, additional, Lefranc, Valentin, additional, Ohm, Stefan, additional, Schüssler, Fabian, additional, Wagner, Stefan, additional, and Collaboration, H.E.S.S., additional
Published: 2023
Full Text: View/download PDF

24. Gain settings for the upgraded H.E.S.S. CT1-4 cameras under moonlight observations

Author: Tomankova, Lenka, Yusafzai, Anke, Kostunin, Dmitriy, Giavitto, Gianluca, Ohm, Stefan, Mitchell, Alison, de Naurois, Mathuie, Lenain, Jean-Philippe, and H. E. S. S. Collaboration
Subjects: instrumentation, very-high energy gamma-ray astronomy, cherenkov cameras, calibration
Abstract: Zenodo (2022). doi:10.5281/ZENODO.7400326 special issue: "HESS technical note", The purpose of this technical document is to assess the effect of a gain reduction on low- and high-level analysis results and to investigate the option of using a common lowered gain for both, dark and moonlight observations. Using a sequence of six Crab Nebula runs taken at alternating gain settings, it was shown that decreasing the gain factor from 80 to 60 Analog-to-digital counts per photo-electron (ADC/pe) has no significant effect on the telescope system sensitivity under dark-sky conditions. This result confirms expectations that such a change in gain has a comparatively small effect on the signal readout. In particular, the following results were obtained: 1. The trigger rates and event statistics are comparable for both gains. 2. The distributions of Hillas parameters are consistent for both gains. 3. The spectral analysis results are consistent within about 10%. The efficiency of detecting gamma rays is energy-independent and consistent for both gains, indicating no loss of performance at any energy., Published by Zenodo
Published: 2022
Full Text: View/download PDF

25. Gammablitz aus der kosmischen Nachbarschaft

Author: Taylor, Andrew M., primary, Zhu, Sylvia J., additional, Konno, Ruslan, additional, and Ohm, Stefan, additional
Published: 2022
Full Text: View/download PDF

26. Time-resolved hadronic particle acceleration in the recurrent nova RS Ophiuchi

Author: De Wolf, Stefaan, Aharonian, F., Berge, D., O'Brien, P., Ohm, Stefan, Olivera-Nieto, L., Wilhelmi, E. de Ona, Ostrowski, M., Panny, S., Panter, M., Parsons, R. D., Peron, G., Pita, S., Bernlöhr, K., Poireau, V., Prokhorov, D. A., Prokoph, H., Pühlhofer, G., Punch, M., Quirrenbach, A., Reichherzer, P., Reimer, A., Reimer, O., Renaud, M., Bi, B., Reville, B., Rieger, F., Rowell, G., Rudak, B., Ricarte, H. Rueda, Ruiz-Velasco, E., Sahakian, V., Sailer, S., Salzmann, H., Sanchez, D. A., Böttcher, M., Santangelo, A., Sasaki, M., Schäfer, J., Schüssler, F., Schutte, H. M., Schwanke, U., Senniappan, M., Shapopi, J. N. S., Simoni, R., Sinha, A., Boisson, C., Sol, H., Specovius, A., Spencer, S., Stawarz, Ł., Steinmassl, S., Steppa, C., Takahashi, T., Tanaka, T., Taylor, A. M., Terrier, R., Bolmont, J., Thorpe-Morgan, C., Tsirou, M., Tsuji, N., Tuffs, R., Uchiyama, Y., Unbehaun, T., van Eldik, C., van Soelen, B., Veh, J., Venter, C., de Bony de Lavergne, M., Vink, J., Wagner, S. J., Werner, F., White, R., Wierzcholska, A., Wong, Yu Wun, Yusafzai, A., Zacharias, M., Zargaryan, D., Zdziarski, A. A., Breuhaus, M., Zech, A., Zhu, S. J., Zouari, S., Żywucka, N., H. E. S. S. Collaboration, Brose, R., Brun, F., Benkhali, F. Ait, Caroff, S., Casanova, S., Cerruti, M., Chand, T., Chen, A., Cotter, G., Mbarubucyeye, J. Damascene, Djannati-Ataï, A., Dmytriiev, A., Doroshenko, V., Angüner, E. O., Duffy, C., Egberts, K., Ernenwein, J.-P., Fegan, S., Feijen, K., Fiasson, A., de Clairfontaine, G. Fichet, Fontaine, G., Füßling, M., Funk, S., Ashkar, H., Gabici, S., Gallant, Y. A., Ghafourizadeh, S., Giavitto, G., Giunti, L., Glawion, D., Glicenstein, J. F., Grondin, M.-H., Hermann, G., Hinton, J. A., Backes, M., Hörbe, M., Hofmann, W., Hoischen, C., Holch, T. L., Holler, M., Horns, D., Huang, Zhiqiu, Jamrozy, M., Jankowsky, F., Jung-Richardt, I., Baghmanyan, V., Kasai, E., Katarzyński, K., Katz, U., Khangulyan, D., Khélifi, B., Klepser, S., Kluźniak, W., Komin, Nu., Konno, R., Kosack, K., Martins, V. Barbosa, Kostunin, D., Stum, S. Le, Lemière, A., Lemoine-Goumard, M., Lenain, J.-P., Leuschner, F., Lohse, T., Luashvili, A., Lypova, I., Mackey, J., Batzofin, R., Malyshev, D., Marandon, V., Marchegiani, P., Marcowith, A., Martí-Devesa, G., Marx, R., Maurin, G., Meyer, M., Mitchell, Alison, Moderski, R., Becherini, Y., Mohrmann, L., Montanari, A., Moulin, E., Muller, J., Murach, T., Nakashima, K., de Naurois, M., Nayerhoda, A., Niemiec, J., Noel, A. Priyana, High Energy Astrophys. & Astropart. Phys (API, FNWI), Gravitation and Astroparticle Physics Amsterdam, H.E.S.S. Collaboration, 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), 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), 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, 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 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), 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 Particules de Montpellier (LUPM), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM), Laboratoire de Physique des Deux Infinis Bordeaux (LP2I - Bordeaux), Université de Bordeaux (UB)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), and H.E.S.S.
Subjects: High Energy Astrophysical Phenomena (astro-ph.HE), Multidisciplinary, Astrophysics::High Energy Astrophysical Phenomena, ddc:320, FOS: Physical sciences, HESS - Abteilung Hinton, Astrophysics::Solar and Stellar Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Astrophysics - High Energy Astrophysical Phenomena, Astrophysics::Galaxy Astrophysics
Abstract: Science / Science now 376(6588), 77 - 80 (2022). doi:10.1126/science.abn0567, Recurrent novae are repeating thermonuclear explosions in the outer layers of white dwarfs, due to the accretion of fresh material from a binary companion. The shock generated when ejected material slams into the companion star’s wind can accelerate particles. We report very-high-energy (VHE; ≳100 giga–electron volts≳100 giga–electron volts) gamma rays from the recurrent nova RS Ophiuchi, up to 1 month after its 2021 outburst, observed using the High Energy Stereoscopic System (H.E.S.S.). The temporal profile of VHE emission is similar to that of lower-energy giga–electron volt emission, indicating a common origin, with a 2-day delay in peak flux. These observations constrain models of time-dependent particle energization, favoring a hadronic emission scenario over the leptonic alternative. Shocks in dense winds provide favorable environments for efficient acceleration of cosmic rays to very high energies., Published by Assoc., Washington, DC
Published: 2022
Full Text: View/download PDF

27. Evidence of 100 TeV γ-ray emission from HESS J1702-420

Author: Abdalla, H., Aharonian, F., Barbosa Martins, Victor, Lemoine-Goumard, M., Lenain, J.-P., Leuschner, F., Levy, C., Lohse, T., Lypova, Iryna, Mackey, J., Majumdar, Jhilik, Malyshev, D., Barnacka, A., Marandon, V., Marchegiani, P., Marcowith, A., Mares, A., Martí-Devesa, G., Marx, R., Maurin, G., Meintjes, P. J., Meyer, M., Mitchell, A., Barnard, M., Moderski, R., Mohrmann, L., Montanari, A., Moore, C., Morris, P., Moulin, E., Muller, J., Murach, Thomas, Nakashima, K., Nayerhoda, A., Becherini, Y., de Naurois, M., Ndiyavala, H., Niemiec, J., Oakes, L., O'Brien, P., Odaka, H., Ohm, Stefan, Olivera-Nieto, L., de Ona Wilhelmi, Emma Maria, Ostrowski, M., Berge, D., Panny, S., Panter, M., Parsons, R. D., Peron, G., Peyaud, B., Piel, Q., Pita, S., Poireau, V., Noel, A. Priyana, Prokhorov, D. A., Bernlöhr, K., Prokoph, Heike, Pühlhofer, G., Punch, M., Quirrenbach, A., Raab, S., Rauth, R., Reichherzer, P., Reimer, A., Reimer, O., Remy, Q., Bi, B., Renaud, M., Rieger, F., Rinchiuso, L., Romoli, C., Rowell, G., Rudak, B., Ruiz-Velasco, E., Sahakian, V., Sailer, S., Salzmann, H., Böttcher, M., Sanchez, D. A., Santangelo, A., Sasaki, M., Scalici, M., Schäfer, J., Schüssler, F., Schutte, H. M., Schwanke, U., Seglar-Arroyo, M., Senniappan, M., Boisson, C., Seyffert, A. S., Shafi, N., Shapopi, J. N. S., Shiningayamwe, K., Simoni, R., Sinha, A., Sol, H., Specovius, A., Spencer, S., Spir-Jacob, M., Bolmont, J., Stawarz, L., Sun, L., Steenkamp, R., Stegmann, Christian, Steinmassl, S., Steppa, C., Takahashi, T., Tavernier, T., Taylor, Andrew, Terrier, R., Benkhali, F. Ait, de Bony de Lavergne, M., Thiersen, J. H. E., Tiziani, D., Tluczykont, M., Tomankova, L., Trichard, C., Tsirou, M., Tuffs, R., Uchiyama, Y., van der Walt, D. J., van Eldik, C., Breuhaus, M., van Rensburg, C., van Soelen, B., Vasileiadis, G., Veh, J., Venter, C., Vincent, P., Vink, J., Völk, H. J., Wadiasingh, Z., Wagner, S. J., Brun, F., Watson, J., Werner, F., White, R., Wierzcholska, A., Wong, Yu Wun, Yusafzai, A., Zacharias, M., Zanin, R., Zargaryan, D., Zdziarski, A. A., Brun, P., Zech, A., Zhu, Sylvia Jiechen, Zorn, J., Zouari, S., Żywucka, N., Acero, F., H. E. S. S. Collaboration, Bryan, M., Büchele, M., Bulik, T., Bylund, T., Caroff, S., Carosi, A., Angüner, E. O., Casanova, S., Chand, T., Chandra, S., Chen, A., Cotter, G., Curyło, M., Mbarubucyeye, Jean Damascene, Davids, I. D., Davies, J., Deil, C., Arcaro, C., Devin, J., Dirson, L., Djannati-Ataï, A., Dmytriiev, A., Donath, A., Doroshenko, V., Dreyer, L., Duffy, C., Dyks, J., Egberts, K., Armand, C., Eichhorn, F., Einecke, S., Emery, G., Ernenwein, J.-P., Feijen, K., Fegan, S., Fiasson, A., Fichet de Clairfontaine, G., Fontaine, G., Funk, S., Armstrong, T., Füssling, Matthias, Gabici, S., Gallant, Y. A., Giavitto, Gianluca, Giunti, L., Glawion, D., Glicenstein, J. F., Grondin, M.-H., Hahn, J., Haupt, Maria, Ashkar, H., Hermann, G., Hinton, J. A., Hofmann, W., Hoischen, C., Holch, Tim Lukas, Holler, M., Hörbe, M., Horns, D., Huber, D., Jamrozy, M., Backes, M., Jankowsky, D., Jankowsky, F., Jardin-Blicq, A., Joshi, V., Jung-Richardt, I., Kasai, E., Kastendieck, M. A., Katarzyński, K., Katz, U., Khangulyan, D., Baghmanyan, V., Khélifi, B., Klepser, S., Kluźniak, W., Komin, Nu., Konno, Ruslan, Kosack, K., Kostunin, D., Kreter, M., Lamanna, G., Lemière, A., 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), 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, 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)-Université Paris Diderot - Paris 7 (UPD7)-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), 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 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 Univers et Particules de Montpellier (LUPM), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Montpellier (UM)-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), H.E.S.S., 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 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), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-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), 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), 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), 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), Gravitation and Astroparticle Physics Amsterdam, and High Energy Astrophys. & Astropart. Phys (API, FNWI)
Subjects: Photon, dimension: 3, Hadron, Astrophysics, GeV, 01 natural sciences, law.invention, law, HESS, Spectral slope, site, High Energy Stereoscopic System, Ultra-high-energy cosmic ray, 010303 astronomy & astrophysics, energy spectrum [gamma ray], Physics, energy: high, cosmic radiation: spectrum, Gamma ray, non-thermal [radiation mechanisms], 3. Good health, curvature, 3 [dimension], high [energy], Astrophysics - High Energy Astrophysical Phenomena, Astrophysics::High Energy Astrophysical Phenomena, UHE [cosmic radiation], Context (language use), Cosmic ray, gamma ray: energy spectrum, GLAST, energy [p], solids, cosmic rays, 5/3, 0103 physical sciences, data analysis [methods], TeV, spectrum [cosmic radiation], cosmic radiation: UHE, 010308 nuclear & particles physics, Astronomy and Astrophysics, Particle accelerator, acceleration, Galaxy, p: energy, Space and Planetary Science, ddc:520, spectral, galaxy, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], general [gamma rays], Energy (signal processing), Fermi Gamma-ray Space Telescope
Abstract: The identification of PeVatrons, hadronic particle accelerators reaching the knee of the cosmic ray spectrum (few $10^{15}$ eV), is crucial to understand the origin of cosmic rays in the Galaxy. We provide an update on the unidentified source HESS J1702-420, a promising PeVatron candidate. We present new observations of HESS J1702-420 made with the High Energy Stereoscopic System (H.E.S.S.), and processed using improved analysis techniques. The analysis configuration was optimized to enhance the collection area at the highest energies. We applied a three-dimensional (3D) likelihood analysis to model the source region and adjust non thermal radiative spectral models to the $\gamma$-ray data. We also analyzed archival data from the Fermi Large Area Telescope (LAT) to constrain the source spectrum at $\gamma$-ray energies >10 GeV. We report the detection of a new source component called HESS J1702-420A, that was separated from the bulk of TeV emission at a $5.4\sigma$ confidence level. The power law $\gamma$-ray spectrum of HESS J1702-420A extends with an index of $\Gamma=1.53\pm0.19_\text{stat}\pm0.20_\text{sys}$ and without curvature up to the energy band 64-113 TeV, in which it was detected by H.E.S.S. at a $4.0\sigma$ confidence level. This brings evidence for the source emission up to $100\,\text{TeV}$, which makes HESS J1702-420A a compelling candidate site for the presence of extremely high energy cosmic rays. Remarkably, in a hadronic scenario, the cut-off energy of the proton distribution powering HESS J1702-420A is found to be higher than 0.5 PeV at a 95% confidence level. HESS J1702-420A becomes therefore one of the most solid PeVatron candidates detected so far in H.E.S.S. data, altough a leptonic origin of its emission could not be ruled out either., Comment: Accepted for publication in the 2. Astrophysical processes section of Astronomy & Astrophysics
Published: 2021
Full Text: View/download PDF

28. Revisiting the PeVatron candidate MGRO J1908+06 with an updated H.E.S.S. analysis

Author: Abdalla, Hassan, Aharonian, Felix, Barbosa Martins, Victor, Lohse, Thomas, Luashvili, Anna, Lypova, Iryna, Mackey, Jonathan, Majumdar, Jhilik, Malyshev, Denys, MALYSHEV, Dmitry, Marandon, Vincent, Marchegiani, Paolo, Marcowith, Alexandre, Barnacka, Anna, Mares, Arnaud, Marti'i-Devesa, Guillem, Marx, Ramin, Maurin, Gilles, Meintjes, Pieter, Meyer, Manuel, Moderski, Rafal, Mohrmann, Lars, de Ona Wilhelmi, E., Joshi, Vikas, Barnard, Monica, Mitchell, Alison, Montanari, Alessandro, Moore, Chris, Morris, Paul, Moulin, Emmanuel, Muller, Jacques, Murach, Thomas, Nakashima, Kaori, Naurois , Mathieu, Nayerhoda, Amid, Batzofin, Rowan, Ndiyavala, Hambeleleni, Niemiec, Jacek, Noel, Angel, O'Brien, Paul, Oberholzer, Laenita Lorraine, Ohm, Stefan, Khelifi, Bruno, Giunti, Luca, Olivera-Nieto, Laura, de Ona Wilhelmi, Emma Maria, Becherini, Yvonne, Ostrowski, Michal, Panny, Sebastian, Panter, Michael, Parsons, Dan, Peron, Giada, Pita, Santiago, Poireau, Vincent, Prokhorov, Dmitry, Prokoph, Heike, PUEHLHOFER, Gerd, Berge, David, Punch, Michael, Quirrenbach, Andreas, Reichherzer, Patrick, Reimer, Anita, Reimer, Olaf, Remy, Quentin, Renaud, Matthieu, Reville, Brian, Rieger, Frank, Romoli, Carlo, Bernloehr, Konrad, Rowell, Gavin, Rudak, Bronislaw, Rueda Ricarte, Hector, Ruiz Velasco, Edna, Sahakian, Vardan, Sailer, Simon, Salzmann, Heiko, Sanchez, David, Santangelo, Andrea, Sasaki, Manami, Bi, Baiyang, Schaefer, Johannes, Schutte, Hester, Schwanke, Ullrich, Schüssler, Fabian, Senniappan, Mohanraj, Seyffert, Albert, Shapopi, Jimmy N. S., Shiningayamwe, Kleopas, Simoni, Rachel, Sinha, Atreyee, Boettcher, Markus, Sol, Helene, Spackman, Hugh, Specovius, Andreas, Spencer, Samuel Timothy, Spir-Jacob, Marion, Stawarz, Lukasz, Steenkamp, Riaan, Stegmann, Christian, Steinmassl, Simon, Steppa, Constantin, Boisson, Catherine, Sun, Lei, Takahashi, Tadayuki, Tanaka, Takaaki, Tavernier, Thomas, Taylor, Andrew, Terrier, Regis, Thiersen, Hannes, Thorpe-Morgan, Charles, Tluczykont, Martin, Tomankova, Lenka, Ait-Benkhali, Faical, Bolmont, Julien, Tsirou, Michelle, Tsuji, Naomi, Tuffs, Richard, Uchiyama, Yasunobu, van der Walt, Johann, van Eldik, Christopher, van Rensburg, Carlo, van Soelen, Brian, Vasileiadis, George, Veh, Johannes, Bony , Mathieu, Venter, Christo, Vincent, Pascal, Vink, Jacco, Völk, Heinrich J., Wagner, Stefan, Watson, Jason John, Werner, Felix, White, Richard, Wierzcholska, Alicja, Wong, Yu Wun, Breuhaus, Mischa, Yassin, Hend, Yusafzai, Anke, Zacharias, Michael, Zanin, Roberta, Zargaryan, Davit, Zdziarski, Andrzej, Zech, Andreas, Zhu, Sylvia Jiechen, Zmija, Andreas, Zouari, Samuel, Brose, Robert, Zywucka, Natalia, H. E. S. S. Collaboration, Brun, Francois, Bulik, Tomasz, Bylund, Thomas, Cangemi, Floriane, Caroff, Sami, Casanova, Sabrina, Anguener, Oguzhan, Catalano, Jaqueline, Chambery, Pauline, Chand, Tej Bahadur, Chen, Andrew, Cotter, Garret, Curlo, Malgorzata, Dalgleish, Hannah, Mbarubucyeye, Jean Damascene, Davids, Isak Delberth, Davies, James, Arcaro, Cornelia, Devin, Justine, Djannati-Ataï, Arache, Dmytriiev, Anton, Donath, Axel, Doroshenko, Victor, Dreyer, Lente, Du Plessis, Louis, Duffy, Connor, Egberts, Kathrin, Einecke, Sabrina, Armand, Celine, ERNENWEIN, Jean-Pierre, Fegan, Steven, Feijen, Kirsty, Fiasson, Armand, Fichet de Clairfontaine, Gaëtan, Fontaine, Gerard, Frans, Lott, Füssling, Matthias, Funk, Stefan, Gabici, Stefano, Armstrong, Tom, Gallant, Yves, Giavitto, Gianluca, Glawion, Dorit, Glicenstein, Jean-Francois, Grondin, Marie-Hélène, Hattingh, Sumari, Haupt, Maria, HERMANN, German, Hinton, Jim, Hofmann, Werner, Ashkar, Halim, Hoischen, Clemens, Holch, Tim Lukas, Holler, Markus, Horns, Dieter, Huang, Zhiqiu, Huber, David, Hörbe, Mario, Jamrozy, Marek, Jankowsky, Felix, JUNG, Ira, Backes, Michael, Kasai, Eli, Katarzynski, Krzysztof, Katz, Ulì, Khangulyan, Dmitry, Klepser, Stefan, Kluzniak, Wlodek, Komin, Nukri, Konno, Ruslan, Kosack, Karl, Kostiunin, Dmitriy, Baghmanyan, Vardan, Kreter, Michael, Kukec Mezek, Gašper, Kundu, Anu, Lamanna, Giovanni, Le Stum, Sébastien, Lemiere, Anne, Lemoine-Goumard, Marianne, Lenain, Jean-Philippe, Leuschner, Fabian, Levy, Christelle, 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 de Paris (UP), 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 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), H.E.S.S., Naurois , Mathieu, Bony , Mathieu, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), and Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Photon, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Cosmic ray, Astrophysics, emission [photon], Acceleration, Pulsar, photon: emission, emission [gamma ray], Angular resolution, ddc:530, galaxy [gamma ray], Supernova remnant, Physics, High Energy Astrophysical Phenomena (astro-ph.HE), gamma ray: galaxy, energy: high, cosmic radiation: propagation, Molecular cloud, gamma ray: emission, 13. Climate action, cosmic radiation: galaxy, Milagro, HESS - Abteilung Hinton, high [energy], galaxy [cosmic radiation], propagation [cosmic radiation], Astrophysics - High Energy Astrophysical Phenomena, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract: 37th International Cosmic Ray Conference, ICRC 2021, Berlin, Germany - Online, 12 Jul 2021 - 23 Jul 2021; Proceedings of Science / International School for Advanced Studies (ICRC2021), 779 (2021). doi:10.22323/1.395.0779, Detecting and studying galactic gamma-ray sources emitting very-high energy photons sheds light on the acceleration and propagation of cosmic rays presumably created in these sources. Currently, there are few sources emitting photons with energies exceeding 100 TeV. In this work we revisit the unidentified source MGRO J1908+06, initially detected by Milagro, using an updated H.E.S.S. dataset and analysis pipeline. The vicinity of the source contains a supernova remnant and pulsars as well as molecular clouds. This makes the identification of the primary source(s) of galactic cosmic rays as well as the nature of the gamma-ray emission challenging, especially in light of the recent HAWC and LHAASO detection of the high energy tail of its spectrum. Exploiting the better angular resolution as compared to particle detectors, we investigate the morphology of the source as well as its spectral properties., Published by SISSA, Trieste
Published: 2021
Full Text: View/download PDF

29. A Major Upgrade of the H.E.S.S. Cherenkov Cameras

Author: Lypova Iryna, Giavitto Gianluca, Ashton Terry, Balzer Arnim, Berge David, Brun Francois, Chaminade Thomas, Delagnes Eric, Fontaine Gerard, Füßling Matthias, Giebels Berrie, Glicenstein Jean-Francois, Gräber Tobias, Hinton Jim, Jahnke Albert, Klepser Stefan, Kossatz Marko, Kretzschmann Axel, Lefranc Valentin, Leich Holger, Lüdecke Hartmut, Manigot Pascal, Marandon Vincent, Moulin Emmanuel, de Naurois Mathieu, Nayman Patrick, Ohm Stefan, Penno Marek, Ross Duncan, Salek David, Schade Markus, Schwab Thomas, Simoni Rachel, Stegmann Christian, Steppa Constantin, Thornhill Julian, and Toussnel Francois
Subjects: Physics, QC1-999
Abstract: The High Energy Stereoscopic System (H.E.S.S.) is an array of imaging atmospheric Cherenkov telescopes (IACTs) located in Namibia. It was built to detect Very High Energy (VHE, >100 GeV) cosmic gamma rays, and consists of four 12 m diameter Cherenkov telescopes (CT1-4), built in 2003, and a larger 28 m telescope (CT5), built in 2012. The larger mirror surface of CT5 permits to lower the energy threshold of the array down to 30 GeV. The cameras of CT1-4 are currently undergoing an extensive upgrade, with the goals of reducing their failure rate, reducing their readout dead time and improving the overall performance of the array. The entire camera electronics has been renewed from ground-up, as well as the power, ventilation and pneumatics systems, and the control and data acquisition software. Technical solutions forseen for the next-generation Cherenkov Telescope Array (CTA) observatory have been introduced, most notably the readout is based on the NECTAr analog memory chip. The camera control subsystems and the control software framework also pursue an innovative design, increasing the camera performance, robustness and flexibility. The CT1 camera has been upgraded in July 2015 and is currently taking data; CT2-4 will upgraded in Fall 2016. Together they will assure continuous operation of H.E.S.S at its full sensitivity until and possibly beyond the advent of CTA. This contribution describes the design, the testing and the in-lab and on-site performance of all components of the newly upgraded H.E.S.S. camera.
Published: 2017
Full Text: View/download PDF

30. Observation of burst activity from SGR1935+2154 associated to first galactic FRB with H.E.S.S

Author: Abdalla, Hassan, Aharonian, Felix, Barbosa Martins, Victor, Lenain, Jean-Philippe, Leuschner, Fabian, Levy, Christelle, Lohse, Thomas, Luashvili, Anna, Lypova, Iryna, Mackey, Jonathan, Majumdar, Jhilik, Malyshev, Denys, Malyshev, Dmitry, Barnacka, Anna, Marandon, Vincent, Marchegiani, Paolo, Marcowith, Alexandre, Mares, Arnaud, Martí-Devesa, Guillem, Marx, Ramin, Maurin, Gilles, Meintjes, Pieter, Meyer, Manuel, Mitchell, Alison, Barnard, Monica, Moderski, Rafal, Mohrmann, Lars, Montanari, Alessandro, Moore, Chris, Morris, Paul, Moulin, Emmanuel, Muller, Jacques, Murach, Thomas, Nakashima, Kaori, Naurois , Mathieu, Batzofin, Rowan, Nayerhoda, Amid, Davids, Hambeleleni, Niemiec, Jacek, Noel, Angel, O'Brien, Paul, Oberholzer, Laenita Lorraine, Ohm, Stefan, Olivera-Nieto, Laura, Ona-Wilhelmi , Emma, Ostrowski, Michal, Becherini, Yvonne, Panny, Sebastian, Panter, Michael, Parsons, Dan, Peron, Giada, Pita, Santiago, Poireau, Vincent, Prokhorov, Dmitry, Prokoph, Heike, PUEHLHOFER, Gerd, Punch, Michael, Berge, David, Quirrenbach, Andreas, Reichherzer, Patrick, Reimer, Anita, Reimer, Olaf, Remy, Quentin, Renaud, Matthieu, Reville, Brian, Rieger, Frank, Romoli, Carlo, Rowell, Gavin, Bernloehr, Konrad, Rudak, Bronislaw, Rueda Ricarte, Hector, Ruiz Velasco, Edna, Sahakian, Vardan, Sailer, Simon, Salzmann, Heiko, Sanchez, David, Santangelo, Andrea, Sasaki, Manami, Schaefer, Johannes, Bi, Baiyang, Schutte, Hester, Schwanke, Ullrich, Schüssler, Fabian, Senniappan, Mohanraj, Seyffert, Albert, Shapopi, Jimmy N. S., Shiningayamwe, Kleopas, Simoni, Rachel, Sinha, Atreyee, Sol, Helene, Böttcher, Markus, Spackman, Hugh, Specovius, Andreas, Spencer, Samuel Timothy, Spir-Jacob, Marion, Stawarz, Lukasz, Steenkamp, Riaan, Stegmann, Christian, Steinmassl, Simon, Steppa, Constantin, Sun, Lei, Boisson, Catherine, Takahashi, Tadayuki, Tanaka, Takaaki, Tavernier, Thomas, Taylor, Andrew, Terrier, Regis, Thiersen, Hannes, Thorpe-Morgan, Charles, Tluczykont, Martin, Tomankova, Lenka, Tsirou, Michelle, Ait-Benkhali, Faical, Bolmont, Julien, Tsuji, Naomi, Tuffs, Richard, Uchiyama, Yasunobu, van der Walt, Johann, van Eldik, Christopher, van Rensburg, Carlo, van Soelen, Brian, Vasileiadis, George, Veh, Johannes, Venter, Christo, Bony , Mathieu, Vincent, Pascal, Vink, Jacco, Völk, Heinrich J., Wagner, Stefan, Watson, Jason John, Werner, Felix, White, Richard, Wierzcholska, Alicja, Wong, Yu Wun, Yassin, Hend Mahmoud, Breuhaus, Mischa, Yusafzai, Anke, Zacharias, Michael, Zanin, Roberta, Zargaryan, Davit, Zdziarski, Andrzej, Zech, Andreas, Zhu, Sylvia, Zmija, Andreas, Zouari, Samuel, Żywucka, Natalia, Brose, Robert, H. E. S. S. Collaboration, Brun, Francois, Bulik, Tomasz, Bylund, Thomas, Cangemi, Floriane, Caroff, Sami, Casanova, Sabrina, Anguener, Oguzhan, Catalano, Jaqueline, Chambery, Pauline, Chand, Tej Bahadur, Chen, Andrew, Cotter, Garret, Curlo, Malgorzata, Dalgleish, Hannah, Damascene Mbarubucyeye, Jean, Davids, Isak Delberth, Davies, James, Arcaro, Cornelia, Devin, Justine, Djannati-Ataï, Arache, Dmytriev, Anton, Donath, Axel, Doroshenko, Victor, Dreyer, Lente, Du Plessis, Louis, Duffy, Connor, Egberts, Kathrin, Einecke, Sabrina, Armand, Celine, ERNENWEIN, Jean-Pierre, Fegan, Steven, Feijen, Kirsty, Fiasson, Armand, Fichet de Clairfontaine, Gaëtan, Fontaine, Gerard, Frans, Lott, Fuessling, Matthias, Funk, Stefan, Gabici, Stefano, Armstrong, Tom, Gallant, Yves, Giavitto, Gianluca, Giunti, Luca, Glawion, Dorit, Glicenstein, Jean-Francois, Grondin, Marie-Hélène, Hattingh, Sumari, Haupt, Maria, HERMANN, German, Hinton, Jim, Ashkar, Halim, Hofmann, Werner, Hoischen, Clemens, Holch, Tim, Holler, Markus, Horns, Dieter, Huang, Zhi-Qiu, Huber, David, Hörbe, Mario, Jamrozy, Marek, Jankowsky, Felix, Backes, Michael, Joshi, Vikas, JUNG, Ira, Kasai, Eli, Katarzynski, Krzysztof, Katz, Ulì, Khangulyan, Dmitry, Khelifi, Bruno, Klepser, Stefan, Kluzniak, Wlodek, Komin, Nukri, Baghmanyan, Vardan, Konno, Ruslan, Kosack, Karl, Kostiunin, Dmitriy, Kreter, Michael, Kukec Mezek, Gašper, Kundu, Anu, Lamanna, Giovanni, Le Stum, Sébastien, Lemiere, Anne, Lemoine-Goumard, Marianne, Naurois , Mathieu, Bony , Mathieu, Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, and H.E.S.S.
Subjects: Physics, High Energy Astrophysical Phenomena (astro-ph.HE), Brightness, Astrophysics::High Energy Astrophysical Phenomena, atmosphere [Cherenkov counter], Soft gamma repeater, FOS: Physical sciences, burst [gamma ray], X-ray: burst, Astrophysics, gamma ray: burst, Cherenkov counter: atmosphere, Magnetar, Radio spectrum, Observational evidence, Pulsar, ddc:530, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Astrophysics - High Energy Astrophysical Phenomena, Cherenkov radiation, burst [X-ray]
Abstract: 37th International Cosmic Ray Conference, ICRC2021, Berlin, Germany - Online, 12 Jul 2021 - 23 Jul 2021; Proceedings of Science / International School for Advanced Studies (ICRC2021), 777 (2021). doi:10.22323/1.395.0777, Fast radio bursts (FRB) are enigmatic powerful single radio pulses with durations of several milliseconds and high brightness temperatures suggesting coherent emission mechanism. For the time being a number of extragalactic FRBs have been detected in the high-frequency radio band including repeating ones. The most plausible explanation for these phenomena is magnetar hyperflares. The first observational evidence of this scenario was obtained in April 2020 when an FRB was detected from the direction of the Galactic magnetar and soft gamma repeater SGR1935+2154. The FRB was preceded with a number of soft gamma-ray bursts observed by Swift-BAT satellite, which triggered the follow-up program of the H.E.S.S. imaging atmospheric Cherenkov telescopes (IACTs). H.E.S.S. has observed SGR1935+2154 over a 2 hour window few hours prior to the FRB detection by STARE2 and CHIME. The observations overlapped with other X-ray bursts from the magnetar detected by INTEGRAL and Swift-BAT, thus providing first observations of a magnetar in a flaring state in the very-high energy domain. We present the analysis of these observations, discuss the obtained results and prospects of the H.E.S.S. follow-up program for soft gamma repeaters and anomalous X-ray pulsars., Published by SISSA, Trieste
Published: 2021
Full Text: View/download PDF

31. Search for dark matter annihilation in the Wolf-Lundmark-Melotte dwarf irregular galaxy with H.E.S.S

Author: Abdallah, H., Adam, R., Baghmanyan, V., Lamanna, G., Lemière, A., Lemoine-Goumard, M., Lenain, J.-P., Levy, C., Lohse, T., Lypova, Iryna, Mackey, J., Majumdar, Jhilik, Malyshev, D., Barbosa Martins, Victor, Marandon, V., Marchegiani, P., Marcowith, A., Mares, A., Martì-Devesa, G., Marx, R., Maurin, G., Meintjes, P. J., Meyer, M., Barnacka, A., Moderski, R., Mohamed, M., Mohrmann, L., Montanari, A., Moore, C., Morris, P., Moulin, Jean-Francois, Muller, J., Murach, Thomas, Nakashima, K., Barnard, M., Nayerhoda, A., de Naurois, M., Ndiyavala, H., Niederwanger, F., Niemiec, J., Oakes, L., O'Brien, P., Odaka, H., Ohm, Stefan, Olivera-Nieto, L., Becherini, Y., de Ona Wilhelmi, Emma Maria, Ostrowski, M., Panter, M., Panny, S., Parsons, R. D., Peron, G., Peyaud, B., Piel, Q., Pita, S., Poireau, V., Berge, D., Noel, A. Priyana, Prokhorov, D. A., Prokoph, Heike, Pühlhofer, G., Punch, M., Quirrenbach, A., Raab, S., Rauth, R., Reichherzer, P., Reimer, A., Bernlöhr, K., Reimer, O., Remy, Q., Renaud, M., Rieger, F., Rinchiuso, L., Romoli, C., Rowell, G., Rudak, B., Ruiz-Velasco, E., Sahakian, V., Bi, B., Sailer, S., Sanchez, D. A., Santangelo, A., Sasaki, M., Scalici, M., Schüssler, F., Schutte, H. M., Schwanke, U., Schwemmer, S., Seglar-Arroyo, M., Böttcher, M., Senniappan, M., Seyffert, A. S., Shafi, N., Shiningayamwe, K., Simoni, R., Sinha, A., Sol, H., Specovius, A., Spencer, S., Spir-Jacob, M., Boisson, C., Stawarz, Ł., Sun, L., Steenkamp, R., Stegmann, Christian, Steinmassl, S., Steppa, C., Takahashi, T., Tavernier, T., Taylor, Andrew, Terrier, R., Aharonian, F., Bolmont, J., Tiziani, D., Tluczykont, M., Tomankova, L., Trichard, C., Tsirou, M., Tuffs, R., Uchiyama, Y., van der Walt, D. J., van Eldik, C., van Rensburg, C., de Bony de Lavergne, M., van Soelen, B., Vasileiadis, G., Veh, J., Venter, C., Vincent, P., Vink, J., Völk, H. J., Vuillaume, T., Wadiasingh, Z., Wagner, S. J., Breuhaus, M., Watson, J., Werner, F., White, R., Wierzcholska, A., Wong, Yu Wun, Yusafzai, A., Zacharias, M., Zanin, R., Zargaryan, D., Zdziarski, A. A., Brun, F., Zech, A., Zhu, Sylvia Jiechen, Zorn, J., Zouari, S., Z̀ywucka, N., H. E. S. S. Collaboration, Brun, P., Bryan, M., Büchele, M., Bulik, T., Bylund, T., Caroff, S., Benkhali, F. Ait, Carosi, A., Casanova, S., Chand, T., Chandra, S., Chen, A., Cotter, G., Curyło, M., Mbarubucyeye, Jean Damascene, Davids, I. D., Davies, J., Angüner, E. O., Deil, C., Devin, J., deWilt, P., Dirson, L., Djannati-Ataï, A., Dmytriiev, A., Donath, A., Doroshenko, V., Duffy, C., Dyks, J., Arcaro, C., Egberts, K., Eichhorn, F., Einecke, S., Emery, G., Ernenwein, J.-P., Feijen, K., Fegan, S., Fiasson, A., de Clairfontaine, G. Fichet, Fontaine, G., Armand, C., Funk, S., Füssling, Matthias, Gabici, S., Gallant, Y. A., Giavitto, Gianluca, Giunti, L., Glawion, D., Glicenstein, J. F., Gottschall, D., Grondin, M.-H., Armstrong, T., Hahn, J., Haupt, Maria, Hermann, G., Hinton, J. A., Hofmann, W., Hoischen, C., Holch, T. L., Holler, M., Hörbe, M., Horns, D., Ashkar, H., Huber, D., Jamrozy, M., Jankowsky, D., Jankowsky, F., Jardin-Blicq, A., Joshi, V., Jung-Richardt, I., Kasai, E., Kastendieck, M. A., Katarzyński, K., Backes, M., Katz, U., Khangulyan, D., Khélifi, B., Klepser, S., Kluźniak, W., Komin, Nu., Konno, Ruslan, Kosack, K., Kostunin, D., Kreter, M., 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), 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), 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, 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 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)-Université de Paris (UP), 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)), 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 de Paris (UP), 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), H.E.S.S., Collaboration, H.E.S.S., 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), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Sorbonne Université (SU)-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 Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), 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), Gravitation and Astroparticle Physics Amsterdam, and High Energy Astrophys. & Astropart. Phys (API, FNWI)
Subjects: atmosphere [Cherenkov counter], Astrophysics::High Energy Astrophysical Phenomena, Dark matter, VHE [gamma ray], Cosmic ray, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, GeV, Cherenkov counter: atmosphere, 01 natural sciences, Cosmology, annihilation [dark matter], S030DMA, cosmic rays, S046PHB, HESS, 0103 physical sciences, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], TeV, Experiments in gravity, ddc:530, photon photon, High Energy Stereoscopic System, high energy physics - experiment, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Dwarf galaxy, Physics, Experiments in gravity, cosmology, cosmic rays, astrophysics - high energy astrophysical phenomena, Annihilation, 010308 nuclear & particles physics, imaging, dark matter: annihilation, Galaxy, gamma ray: VHE, kinematics, galaxy, Irregular galaxy, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], cosmology
Abstract: Physical review / D 103(10), 102002 (2021). doi:10.1103/PhysRevD.103.102002, We search for an indirect signal of dark matter through very high-energy γ rays from the Wolf-Lundmark-Melotte (WLM) dwarf irregular galaxy. The pair annihilation of dark matter particles would produce Standard Model particles in the final state such as γ rays, which might be detected by ground-based Cherenkov telescopes. Dwarf irregular galaxies represent promising targets as they are dark matter dominated objects with well-measured kinematics and small uncertainties on their dark matter distribution profiles. In 2018, the five-telescopes of the high energy stereoscopic system observed the dwarf irregular galaxy WLM for 18 hours. We present the first analysis based on data obtained from an imaging atmospheric Cherenkov telescope for this subclass of dwarf galaxy. As we do not observe any significant excess in the direction of WLM, we interpret the result in terms of constraints on the velocity-weighted cross section for dark matter pair annihilation ⟨σv⟩ as a function of the dark matter particle mass for various continuum channels, as well as the prompt γγ emission. For the τ+τ- channel, the limits reach a ⟨σv⟩ value of about 4×10-22 cm3 s-1 for a dark matter particle mass of 1 TeV. For the prompt γγ channel, the upper limit reaches a ⟨σv⟩ value of about 5×10-24 cm3 s-1 for a mass of 370 GeV. These limits represent an improvement of up to a factor 200, with respect to previous results for the dwarf irregular galaxies for TeV dark matter search., Published by Inst., Melville, NY
Published: 2021
Full Text: View/download PDF

32. Astronomy outreach in Namibia: H.E.S.S. and beyond

Author: Dalgleish, Hannah, primary, Prokoph, Heike, additional, Zhu, Sylvia, additional, Backes, Michael, additional, Cotter, Garret, additional, Catalano, Jacqueline, additional, Ruiz Velasco, Edna, additional, Kasai, Eli, additional, Abdalla, Hassan, additional, Aharonian, Felix, additional, Ait-Benkhali, Faical, additional, Anguener, Oguzhan, additional, Arcaro, Cornelia, additional, Armand, Celine, additional, Armstrong, Tom, additional, Ashkar, Halim, additional, Baghmanyan, Vardan, additional, Barbosa Martins, Victor, additional, Barnacka, Anna, additional, Barnard, Monica, additional, Batzofin, Rowan William, additional, Becherini, Yvonne, additional, Berge, David, additional, Bernloehr, Konrad, additional, Bi, Baiyang, additional, Böttcher, Markus, additional, Boisson, Catherine, additional, Bolmont, Julien, additional, Bony (de), Mathieu, additional, Breuhaus, Mischa, additional, Brose, Robert, additional, Brun, Francois, additional, Bulik, Tomasz, additional, Bylund, Thomas, additional, Cangemi, Floriane, additional, Caroff, Sami, additional, Casanova, Sabrina, additional, Catalano, Jaqueline, additional, Chambery, Pauline, additional, Chand, Tej Bahadur, additional, Chen, Andrew, additional, Curlo, Malgorzata, additional, Damascene Mbarubucyeye, Jean, additional, Davids, Isak Delberth, additional, Davies, James, additional, Devin, Justine, additional, Djannati-Ataï, Arache, additional, Dmytriiev, Anton, additional, Donath, Axel, additional, Doroshenko, Victor, additional, Dreyer, Lente, additional, Du Plessis, Louis, additional, Duffy, Connor, additional, Egberts, Kathrin, additional, Einecke, Sabrina, additional, ERNENWEIN, Jean-Pierre, additional, Fegan, Steven, additional, Feijen, Kirsty, additional, Fiasson, Armand, additional, Fichet de Clairfontaine, Gaëtan, additional, Fontaine, Gerard, additional, Frans, Lott, additional, Fuessling, Matthias, additional, Funk, Stefan, additional, Gabici, Stefano, additional, Gallant, Yves, additional, Giavitto, Gianluca, additional, Giunti, Luca, additional, Glawion, Dorit, additional, Glicenstein, Jean-Francois, additional, Grondin, Marie-Hélène, additional, Hattingh, Sumari, additional, Haupt, Maria, additional, HERMANN, German, additional, Hinton, Jim, additional, Hofmann, Werner, additional, Hoischen, Clemens, additional, Holch, Tim, additional, Holler, Markus, additional, Horns, Dieter, additional, Huang, Zhi-Qiu, additional, Huber, David, additional, Hörbe, Mario, additional, Jamrozy, Marek, additional, Jankowsky, Felix, additional, Joshi, Vikas, additional, JUNG, Ira, additional, Katarzynski, Krzysztof, additional, Katz, Ulì, additional, Khangulyan, Dmitry, additional, Khelifi, Bruno, additional, Klepser, Stefan, additional, Kluzniak, Wlodek, additional, Komin, Nukri, additional, Konno, Ruslan, additional, Kosack, Karl, additional, Kostunin, Dmitriy, additional, Kreter, Michael, additional, Kukec Mezek, Gašper, additional, Kundu, Anu, additional, Lamanna, Giovanni, additional, Le Stum, Sebastien, additional, Lemiere, Anne, additional, Lemoine-Goumard, Marianne, additional, Lenain, Jean-Philippe, additional, Leuschner, Fabian, additional, Levy, Christelle, additional, Lohse, Thomas, additional, Luashvili, Anna, additional, Lypova, Iryna, additional, Mackey, Jonathan, additional, Majumdar, Jhilik, additional, Malyshev, Denys, additional, Malyshev, Dmitry, additional, Marandon, Vincent, additional, Marchegiani, Paolo, additional, Marcowith, Alexandre, additional, Mares, Arnaud, additional, Martí-Devesa, Guillem, additional, Marx, Ramin, additional, Maurin, Gilles, additional, Meintjes, Pieter, additional, Meyer, Manuel, additional, Mitchell, Alison, additional, Moderski, Rafal, additional, Mohrmann, Lars, additional, Montanari, Alessandro, additional, Moore, Chris, additional, Morris, Paul, additional, Moulin, Emmanuel, additional, Muller, Jacques, additional, Murach, Thomas, additional, Nakashima, Kaori, additional, Naurois (de), Mathieu, additional, Nayerhoda, Amid, additional, Davids, Hambeleleni, additional, Niemiec, Jacek, additional, Noel, Angel, additional, O'Brien, Paul, additional, Oberholzer, Laenita Lorraine, additional, Ohm, Stefan, additional, Olivera-Nieto, Laura, additional, Ona-Wilhelmi (de), Emma, additional, Ostrowski, Michal, additional, Panny, Sebastian, additional, Panter, Michael, additional, Parsons, Dan, additional, Peron, Giada, additional, Pita, Santiago, additional, Poireau, Vincent, additional, Prokhorov, Dmitry A, additional, PUEHLHOFER, Gerd, additional, Punch, Michael, additional, Quirrenbach, Andreas, additional, Reichherzer, Patrick, additional, Reimer, Anita, additional, Reimer, Olaf, additional, Remy, Quentin, additional, Renaud, Matthieu, additional, Reville, Brian, additional, Rieger, Frank, additional, Romoli, Carlo, additional, Rowell, Gavin P, additional, Rudak, Bronislaw, additional, Rueda Ricarte, Hector, additional, Sahakian, Vardan, additional, Sailer, Simon, additional, Salzmann, Heiko, additional, Sanchez, David, additional, Santangelo, Andrea, additional, Sasaki, Manami, additional, Schaefer, Johannes, additional, Schutte, Hester, additional, Schwanke, Ullrich, additional, Schüssler, Fabian, additional, Senniappan, Mohanraj, additional, Seyffert, Albert, additional, Shapopi, Jimmy N.S., additional, Shiningayamwe, Kleopas, additional, Simoni, Rachel, additional, Sinha, Atreyee, additional, Sol, Helene, additional, Spackman, Hugh, additional, Specovius, Andreas, additional, Spencer, Samuel Timothy, additional, Spir-Jacob, Marion, additional, Stawarz, Lukasz, additional, Steenkamp, Riaan, additional, Stegmann, Christian, additional, Steinmassl, Simon, additional, Steppa, Constantin, additional, Sun, Lei, additional, Takahashi, Tadayuki, additional, Tanaka, Takaaki, additional, Tavernier, Thomas, additional, Taylor, Andrew, additional, Terrier, Regis, additional, Thiersen, Hannes, additional, Thorpe-Morgan, Charles, additional, Tluczykont, Martin, additional, Tomankova, Lenka, additional, Tsirou, Michelle, additional, Tsuji, Naomi, additional, Tuffs, Richard, additional, Uchiyama, Yasunobu, additional, van der Walt, Johann, additional, van Eldik, Christopher, additional, van Rensburg, Carlo, additional, van Soelen, Brian, additional, Vasileiadis, George, additional, Veh, Johannes, additional, Venter, Christo, additional, Vincent, Pascal, additional, Vink, Jacco, additional, Völk, Heinrich J., additional, Wagner, Stefan, additional, Watson, Jason John, additional, Werner, Felix, additional, White, Richard, additional, Wierzcholska, Alicja, additional, Wong, Yu Wun, additional, Yassin, Hend Mahmoud, additional, Yusafzai, Anke, additional, Zacharias, Michael, additional, Zanin, Roberta, additional, Zargaryan, Davit, additional, Zdziarski, Andrzej, additional, Zech, Andreas, additional, Zmija, Andreas, additional, Zouari, Samuel, additional, and Żywucka, Natalia, additional
Published: 2021
Full Text: View/download PDF

33. The young massive stellar cluster Westerlund 1 in gamma rays as seen with H.E.S.S.

Author: Mohrmann, Lars, primary, Abdalla, Hassan, additional, Aharonian, Felix, additional, Ait-Benkhali, Faical, additional, Anguener, Oguzhan, additional, Arcaro, Cornelia, additional, Armand, Celine, additional, Armstrong, Tom, additional, Ashkar, Halim, additional, Backes, Michael, additional, Baghmanyan, Vardan, additional, Barbosa Martins, Victor, additional, Barnacka, Anna, additional, Barnard, Monica, additional, Batzofin, Rowan William, additional, Becherini, Yvonne, additional, Berge, David, additional, Bernloehr, Konrad, additional, Bi, Baiyang, additional, Böttcher, Markus, additional, Boisson, Catherine, additional, Bolmont, Julien, additional, Bony (de), Mathieu, additional, Breuhaus, Mischa, additional, Brose, Robert, additional, Brun, Francois, additional, Bulik, Tomasz, additional, Bylund, Thomas, additional, Cangemi, Floriane, additional, Caroff, Sami, additional, Casanova, Sabrina, additional, Catalano, Jaqueline, additional, Chambery, Pauline, additional, Chand, Tej Bahadur, additional, Chen, Andrew, additional, Cotter, Garret, additional, Curlo, Malgorzata, additional, Dalgleish, Hannah, additional, Damascene Mbarubucyeye, Jean, additional, Davids, Isak Delberth, additional, Davies, James, additional, Devin, Justine, additional, Djannati-Ataï, Arache, additional, Dmytriiev, Anton, additional, Donath, Axel, additional, Doroshenko, Victor, additional, Dreyer, Lente, additional, Du Plessis, Louis, additional, Duffy, Connor, additional, Egberts, Kathrin, additional, Einecke, Sabrina, additional, ERNENWEIN, Jean-Pierre, additional, Fegan, Steven, additional, Feijen, Kirsty, additional, Fiasson, Armand, additional, Fichet de Clairfontaine, Gaëtan, additional, Fontaine, Gerard, additional, Frans, Lott, additional, Fuessling, Matthias, additional, Funk, Stefan, additional, Gabici, Stefano, additional, Gallant, Yves, additional, Giavitto, Gianluca, additional, Giunti, Luca, additional, Glawion, Dorit, additional, Glicenstein, Jean-Francois, additional, Grondin, Marie-Hélène, additional, Hattingh, Sumari, additional, Haupt, Maria, additional, HERMANN, German, additional, Hinton, Jim, additional, Hofmann, Werner, additional, Hoischen, Clemens, additional, Holch, Tim, additional, Holler, Markus, additional, Horns, Dieter, additional, Huang, Zhi-Qiu, additional, Huber, David, additional, Hörbe, Mario, additional, Jamrozy, Marek, additional, Jankowsky, Felix, additional, Joshi, Vikas, additional, JUNG, Ira, additional, Kasai, Eli, additional, Katarzynski, Krzysztof, additional, Katz, Ulì, additional, Khangulyan, Dmitry, additional, Khelifi, Bruno, additional, Klepser, Stefan, additional, Kluzniak, Wlodek, additional, Komin, Nukri, additional, Konno, Ruslan, additional, Kosack, Karl, additional, Kostunin, Dmitriy, additional, Kreter, Michael, additional, Kukec Mezek, Gašper, additional, Kundu, Anu, additional, Lamanna, Giovanni, additional, Le Stum, Sebastien, additional, Lemiere, Anne, additional, Lemoine-Goumard, Marianne, additional, Lenain, Jean-Philippe, additional, Leuschner, Fabian, additional, Levy, Christelle, additional, Lohse, Thomas, additional, Luashvili, Anna, additional, Lypova, Iryna, additional, Mackey, Jonathan, additional, Majumdar, Jhilik, additional, Malyshev, Denys, additional, Malyshev, Dmitry, additional, Marandon, Vincent, additional, Marchegiani, Paolo, additional, Marcowith, Alexandre, additional, Mares, Arnaud, additional, Martí-Devesa, Guillem, additional, Marx, Ramin, additional, Maurin, Gilles, additional, Meintjes, Pieter, additional, Meyer, Manuel, additional, Mitchell, Alison, additional, Moderski, Rafal, additional, Montanari, Alessandro, additional, Moore, Chris, additional, Morris, Paul, additional, Moulin, Emmanuel, additional, Muller, Jacques, additional, Murach, Thomas, additional, Nakashima, Kaori, additional, Naurois (de), Mathieu, additional, Nayerhoda, Amid, additional, Davids, Hambeleleni, additional, Niemiec, Jacek, additional, Noel, Angel, additional, O'Brien, Paul, additional, Oberholzer, Laenita Lorraine, additional, Ohm, Stefan, additional, Olivera-Nieto, Laura, additional, Ona-Wilhelmi (de), Emma, additional, Ostrowski, Michal, additional, Panny, Sebastian, additional, Panter, Michael, additional, Parsons, Dan, additional, Peron, Giada, additional, Pita, Santiago, additional, Poireau, Vincent, additional, Prokhorov, Dmitry A, additional, Prokoph, Heike, additional, PUEHLHOFER, Gerd, additional, Punch, Michael, additional, Quirrenbach, Andreas, additional, Rauth, Romed, additional, Reichherzer, Patrick, additional, Reimer, Anita, additional, Reimer, Olaf, additional, Remy, Quentin, additional, Renaud, Matthieu, additional, Reville, Brian, additional, Rieger, Frank, additional, Romoli, Carlo, additional, Rowell, Gavin P, additional, Rudak, Bronislaw, additional, Rueda Ricarte, Hector, additional, Ruiz Velasco, Edna, additional, Sahakian, Vardan, additional, Sailer, Simon, additional, Salzmann, Heiko, additional, Sanchez, David, additional, Santangelo, Andrea, additional, Sasaki, Manami, additional, Schaefer, Johannes, additional, Schutte, Hester, additional, Schwanke, Ullrich, additional, Schüssler, Fabian, additional, Senniappan, Mohanraj, additional, Seyffert, Albert, additional, Shapopi, Jimmy N.S., additional, Shiningayamwe, Kleopas, additional, Simoni, Rachel, additional, Sinha, Atreyee, additional, Sol, Helene, additional, Spackman, Hugh, additional, Specovius, Andreas, additional, Spencer, Samuel Timothy, additional, Spir-Jacob, Marion, additional, Stawarz, Lukasz, additional, Steenkamp, Riaan, additional, Stegmann, Christian, additional, Steinmassl, Simon, additional, Steppa, Constantin, additional, Sun, Lei, additional, Takahashi, Tadayuki, additional, Tanaka, Takaaki, additional, Tavernier, Thomas, additional, Taylor, Andrew, additional, Terrier, Regis, additional, Thiersen, Hannes, additional, Thorpe-Morgan, Charles, additional, Tluczykont, Martin, additional, Tomankova, Lenka, additional, Tsirou, Michelle, additional, Tsuji, Naomi, additional, Tuffs, Richard, additional, Uchiyama, Yasunobu, additional, van der Walt, Johann, additional, van Eldik, Christopher, additional, van Rensburg, Carlo, additional, van Soelen, Brian, additional, Vasileiadis, George, additional, Veh, Johannes, additional, Venter, Christo, additional, Vincent, Pascal, additional, Vink, Jacco, additional, Völk, Heinrich J., additional, Wagner, Stefan, additional, Watson, Jason John, additional, Werner, Felix, additional, White, Richard, additional, Wierzcholska, Alicja, additional, Wong, Yu Wun, additional, Yassin, Hend Mahmoud, additional, Yusafzai, Anke, additional, Zacharias, Michael, additional, Zanin, Roberta, additional, Zargaryan, Davit, additional, Zdziarski, Andrzej, additional, Zech, Andreas, additional, Zhu, Sylvia, additional, Zmija, Andreas, additional, Zouari, Samuel, additional, and Żywucka, Natalia, additional
Published: 2021
Full Text: View/download PDF

34. Analysis optimisation for more than 10 TeV gamma-ray astronomy with IACTs

Author: Lypova, Iryna, primary, Berge, David, additional, Klepser, Stefan, additional, Kostunin, Dmitriy, additional, Ohm, Stefan, additional, and Wagner, Stefan, additional
Published: 2021
Full Text: View/download PDF

35. Making cosmic particle accelerators visible and audible

Author: Ohm, Stefan, primary, Rappaport, Konrad, additional, Nicolai, Carsten, additional, Mundzeck, Till, additional, Taylor, Andrew, additional, Füßling, Matthias, additional, Zhu, Sylvia Jiechen, additional, and Parsons, Robert Daniel, additional
Published: 2021
Full Text: View/download PDF

36. Detection of new Extreme BL Lac objects with H.E.S.S. and Swift XRT

Author: Noel, Angel Priyana, primary, Abdalla, Hassan, additional, Aharonian, Felix, additional, Ait-Benkhali, Faical, additional, Anguener, Oguzhan, additional, Arcaro, Cornelia, additional, Armand, Celine, additional, Armstrong, Tom, additional, Ashkar, Halim, additional, Backes, Michael, additional, Baghmanyan, Vardan, additional, Barbosa Martins, Victor, additional, Barnacka, Anna, additional, Barnard, Monica, additional, Batzofin, Rowan William, additional, Becherini, Yvonne, additional, Berge, David, additional, Bernloehr, Konrad, additional, Bi, Baiyang, additional, Böttcher, Markus, additional, Boisson, Catherine, additional, Bolmont, Julien, additional, Bony (de), Mathieu, additional, Breuhaus, Mischa, additional, Brose, Robert, additional, Brun, Francois, additional, Bulik, Tomasz, additional, Bylund, Thomas, additional, Cangemi, Floriane, additional, Caroff, Sami, additional, Casanova, Sabrina, additional, Catalano, Jaqueline, additional, Chambery, Pauline, additional, Chand, Tej Bahadur, additional, Chen, Andrew, additional, Cotter, Garret, additional, Curlo, Malgorzata, additional, Dalgleish, Hannah, additional, Damascene Mbarubucyeye, Jean, additional, Davids, Isak Delberth, additional, Davies, James, additional, Devin, Justine, additional, Djannati-Ataï, Arache, additional, Dmytriiev, Anton, additional, Donath, Axel, additional, Doroshenko, Victor, additional, Dreyer, Lente, additional, Du Plessis, Louis, additional, Duffy, Connor, additional, Egberts, Kathrin, additional, Einecke, Sabrina, additional, ERNENWEIN, Jean-Pierre, additional, Fegan, Steven, additional, Feijen, Kirsty, additional, Fiasson, Armand, additional, Fichet de Clairfontaine, Gaëtan, additional, Fontaine, Gerard, additional, Frans, Lott, additional, Fuessling, Matthias, additional, Funk, Stefan, additional, Gabici, Stefano, additional, Gallant, Yves, additional, Giavitto, Gianluca, additional, Giunti, Luca, additional, Glawion, Dorit, additional, Glicenstein, Jean-Francois, additional, Grondin, Marie-Hélène, additional, Hattingh, Sumari, additional, Haupt, Maria, additional, HERMANN, German, additional, Hinton, Jim, additional, Hofmann, Werner, additional, Hoischen, Clemens, additional, Holch, Tim, additional, Holler, Markus, additional, Horns, Dieter, additional, Huang, Zhi-Qiu, additional, Huber, David, additional, Hörbe, Mario, additional, Jamrozy, Marek, additional, Jankowsky, Felix, additional, Joshi, Vikas, additional, JUNG, Ira, additional, Kasai, Eli, additional, Katarzynski, Krzysztof, additional, Katz, Ulì, additional, Khangulyan, Dmitry, additional, Khelifi, Bruno, additional, Klepser, Stefan, additional, Kluzniak, Wlodek, additional, Komin, Nukri, additional, Konno, Ruslan, additional, Kosack, Karl, additional, Kostunin, Dmitriy, additional, Kreter, Michael, additional, Kukec Mezek, Gašper, additional, Kundu, Anu, additional, Lamanna, Giovanni, additional, Le Stum, Sebastien, additional, Lemiere, Anne, additional, Lemoine-Goumard, Marianne, additional, Lenain, Jean-Philippe, additional, Leuschner, Fabian, additional, Levy, Christelle, additional, Lohse, Thomas, additional, Luashvili, Anna, additional, Lypova, Iryna, additional, Mackey, Jonathan, additional, Majumdar, Jhilik, additional, Malyshev, Denys, additional, Malyshev, Dmitry, additional, Marandon, Vincent, additional, Marchegiani, Paolo, additional, Marcowith, Alexandre, additional, Mares, Arnaud, additional, Martí-Devesa, Guillem, additional, Marx, Ramin, additional, Maurin, Gilles, additional, Meintjes, Pieter, additional, Meyer, Manuel, additional, Mitchell, Alison, additional, Moderski, Rafal, additional, Mohrmann, Lars, additional, Montanari, Alessandro, additional, Moore, Chris, additional, Morris, Paul, additional, Moulin, Emmanuel, additional, Muller, Jacques, additional, Murach, Thomas, additional, Nakashima, Kaori, additional, Naurois (de), Mathieu, additional, Nayerhoda, Amid, additional, Davids, Hambeleleni, additional, Niemiec, Jacek, additional, O'Brien, Paul, additional, Oberholzer, Laenita Lorraine, additional, Ohm, Stefan, additional, Olivera-Nieto, Laura, additional, Ona-Wilhelmi (de), Emma, additional, Ostrowski, Michal, additional, Panny, Sebastian, additional, Panter, Michael, additional, Parsons, Dan, additional, Peron, Giada, additional, Pita, Santiago, additional, Poireau, Vincent, additional, Prokhorov, Dmitry A, additional, Prokoph, Heike, additional, PUEHLHOFER, Gerd, additional, Punch, Michael, additional, Quirrenbach, Andreas, additional, Reichherzer, Patrick, additional, Reimer, Anita, additional, Reimer, Olaf, additional, Remy, Quentin, additional, Renaud, Matthieu, additional, Reville, Brian, additional, Rieger, Frank, additional, Romoli, Carlo, additional, Rowell, Gavin P, additional, Rudak, Bronislaw, additional, Rueda Ricarte, Hector, additional, Ruiz Velasco, Edna, additional, Sahakian, Vardan, additional, Sailer, Simon, additional, Salzmann, Heiko, additional, Sanchez, David, additional, Santangelo, Andrea, additional, Sasaki, Manami, additional, Schaefer, Johannes, additional, Schutte, Hester, additional, Schwanke, Ullrich, additional, Schüssler, Fabian, additional, Senniappan, Mohanraj, additional, Seyffert, Albert, additional, Shapopi, Jimmy N.S., additional, Shiningayamwe, Kleopas, additional, Simoni, Rachel, additional, Sinha, Atreyee, additional, Sol, Helene, additional, Spackman, Hugh, additional, Specovius, Andreas, additional, Spencer, Samuel Timothy, additional, Spir-Jacob, Marion, additional, Stawarz, Lukasz, additional, Steenkamp, Riaan, additional, Stegmann, Christian, additional, Steinmassl, Simon, additional, Steppa, Constantin, additional, Sun, Lei, additional, Takahashi, Tadayuki, additional, Tanaka, Takaaki, additional, Tavernier, Thomas, additional, Taylor, Andrew, additional, Terrier, Regis, additional, Thiersen, Hannes, additional, Thorpe-Morgan, Charles, additional, Tluczykont, Martin, additional, Tomankova, Lenka, additional, Tsirou, Michelle, additional, Tsuji, Naomi, additional, Tuffs, Richard, additional, Uchiyama, Yasunobu, additional, van der Walt, Johann, additional, van Eldik, Christopher, additional, van Rensburg, Carlo, additional, van Soelen, Brian, additional, Vasileiadis, George, additional, Veh, Johannes, additional, Venter, Christo, additional, Vincent, Pascal, additional, Vink, Jacco, additional, Völk, Heinrich J., additional, Wagner, Stefan, additional, Watson, Jason John, additional, Werner, Felix, additional, White, Richard, additional, Wierzcholska, Alicja, additional, Wong, Yu Wun, additional, Yassin, Hend Mahmoud, additional, Yusafzai, Anke, additional, Zacharias, Michael, additional, Zanin, Roberta, additional, Zargaryan, Davit, additional, Zdziarski, Andrzej, additional, Zech, Andreas, additional, Zhu, Sylvia, additional, Zmija, Andreas, additional, Zouari, Samuel, additional, and Żywucka, Natalia, additional
Published: 2021
Full Text: View/download PDF

37. Science verification of the new FlashCam-based camera in the 28m telescope of H.E.S.S.

Author: Puehlhofer, Gerd, primary, Bernlöhr, Konrad, additional, Bi, Baiyang, additional, HERMANN, German, additional, Hinton, Jim, additional, Jung-Richardt, Ira, additional, Leuschner, Fabian, additional, Marandon, Vincent, additional, Mitchell, Alison, additional, Mohrmann, Lars, additional, Parsons, Robert Daniel, additional, Sailer, Simon, additional, Salzmann, Heiko, additional, Steinmassl, Simon, additional, Werner, Felix, additional, Abdalla, Hassan, additional, Aharonian, Felix, additional, Ait-Benkhali, Faical, additional, Anguener, Oguzhan, additional, Arcaro, Cornelia, additional, Armand, Celine, additional, Armstrong, Tom, additional, Ashkar, Halim, additional, Backes, Michael, additional, Baghmanyan, Vardan, additional, Barbosa Martins, Victor, additional, Barnacka, Anna, additional, Barnard, Monica, additional, Batzofin, Rowan, additional, Becherini, Yvonne, additional, Berge, David, additional, Bernloehr, Konrad, additional, Böttcher, Markus, additional, Boisson, Catherine, additional, Bolmont, Julien, additional, Bony (de), Mathieu, additional, Breuhaus, Mischa, additional, Brose, Robert, additional, Brun, Francois, additional, Bulik, Tomasz, additional, Bylund, Thomas, additional, Cangemi, Floriane, additional, Caroff, Sami, additional, Casanova, Sabrina, additional, Catalano, Jaqueline, additional, Chambery, Pauline, additional, Chand, Tej Bahadur, additional, Chen, Andrew, additional, Cotter, Garret, additional, Curlo, Malgorzata, additional, Dalgleish, Hannah, additional, Damascene Mbarubucyeye, Jean, additional, Davids, Isak Delberth, additional, Davies, James, additional, Devin, Justine, additional, Djannati-Ataï, Arache, additional, Dmytriev, Anton, additional, Donath, Axel, additional, Doroshenko, Victor, additional, Dreyer, Lente, additional, Du Plessis, Louis, additional, Duffy, Connor, additional, Egberts, Kathrin, additional, Einecke, Sabrina, additional, ERNENWEIN, Jean-Pierre, additional, Fegan, Steven, additional, Feijen, Kirsty, additional, Fiasson, Armand, additional, Fichet de Clairfontaine, Gaëtan, additional, Fontaine, Gerard, additional, Frans, Lott, additional, Fuessling, Matthias, additional, Funk, Stefan, additional, Gabici, Stefano, additional, Gallant, Yves, additional, Giavitto, Gianluca, additional, Giunti, Luca, additional, Glawion, Dorit, additional, Glicenstein, Jean-Francois, additional, Grondin, Marie-Hélène, additional, Hattingh, Sumari, additional, Haupt, Maria, additional, Hörbe, Mario, additional, Hofmann, Werner, additional, Hoischen, Clemens, additional, Holch, Tim, additional, Holler, Markus, additional, Horns, Dieter, additional, Huang, Zhi-Qiu, additional, Huber, David, additional, Jamrozy, Marek, additional, Jankowsky, Felix, additional, Joshi, Vikas, additional, Kasai, Eli, additional, Katarzynski, Krzysztof, additional, Katz, Ulì, additional, Khangulyan, Dmitry, additional, Khelifi, Bruno, additional, Klepser, Stefan, additional, Kluzniak, Wlodek, additional, Komin, Nukri, additional, Konno, Ruslan, additional, Kosack, Karl, additional, Kostunin, Dmitriy, additional, Kreter, Michael, additional, Kukec Mezek, Gašper, additional, Kundu, Anu, additional, Lamanna, Giovanni, additional, Le Stum, Sébastien, additional, Lemiere, Anne, additional, Lemoine-Goumard, Marianne, additional, Lenain, Jean-Philippe, additional, Levy, Christelle, additional, Lohse, Thomas, additional, Luashvili, Anna, additional, Lypova, Iryna, additional, Mackey, Jonathan, additional, Majumdar, Jhilik, additional, Malyshev, Denys, additional, Malyshev, Dmitry, additional, Marchegiani, Paolo, additional, Marcowith, Alexandre, additional, Mares, Arnaud, additional, Martí-Devesa, Guillem, additional, Marx, Ramin, additional, Maurin, Gilles, additional, Meintjes, Pieter, additional, Meyer, Manuel, additional, Moderski, Rafal, additional, Montanari, Alessandro, additional, Moore, Chris, additional, Morris, Paul, additional, Moulin, Emmanuel, additional, Muller, Jacques, additional, Murach, Thomas, additional, Nakashima, Kaori, additional, Naurois (de), Mathieu, additional, Nayerhoda, Amid, additional, Davids, Hambeleleni, additional, Niemiec, Jacek, additional, Noel, Angel, additional, O'Brien, Paul, additional, Oberholzer, Laenita Lorraine, additional, Ohm, Stefan, additional, Olivera-Nieto, Laura, additional, Ona-Wilhelmi (de), Emma, additional, Ostrowski, Michal, additional, Panny, Sebastian, additional, Panter, Michael, additional, Parsons, Dan, additional, Peron, Giada, additional, Pita, Santiago, additional, Poireau, Vincent, additional, Prokhorov, Dmitry, additional, Prokoph, Heike, additional, Punch, Michael, additional, Quirrenbach, Andreas, additional, Reichherzer, Patrick, additional, Reimer, Anita, additional, Reimer, Olaf, additional, Remy, Quentin, additional, Renaud, Matthieu, additional, Reville, Brian, additional, Rieger, Frank, additional, Romoli, Carlo, additional, Rowell, Gavin, additional, Rudak, Bronislaw, additional, Rueda Ricarte, Hector, additional, Ruiz Velasco, Edna, additional, Sahakian, Vardan, additional, Sanchez, David, additional, Santangelo, Andrea, additional, Sasaki, Manami, additional, Schaefer, Johannes, additional, Schüssler, Fabian, additional, Schutte, Hester, additional, Schwanke, Ullrich, additional, Senniappan, Mohanraj, additional, Seyffert, Albert, additional, Shapopi, Jimmy N.S., additional, Shiningayamwe, Kleopas, additional, Simoni, Rachel, additional, Sinha, Atreyee, additional, Sol, Helene, additional, Spackman, Hugh, additional, Specovius, Andreas, additional, Spencer, Samuel Timothy, additional, Spir-Jacob, Marion, additional, Stawarz, Lukasz, additional, Steenkamp, Riaan, additional, Stegmann, Christian, additional, Steppa, Constantin, additional, Sun, Lei, additional, Takahashi, Tadayuki, additional, Tanaka, Takaaki, additional, Tavernier, Thomas, additional, Taylor, Andrew, additional, Terrier, Regis, additional, Thiersen, Hannes, additional, Thorpe-Morgan, Charles, additional, Tluczykont, Martin, additional, Tomankova, Lenka, additional, Tsirou, Michelle, additional, Tsuji, Naomi, additional, Tuffs, Richard, additional, Uchiyama, Yasunobu, additional, van der Walt, Johann, additional, van Eldik, Christopher, additional, van Rensburg, Carlo, additional, van Soelen, Brian, additional, Vasileiadis, George, additional, Veh, Johannes, additional, Venter, Christo, additional, Vincent, Pascal, additional, Vink, Jacco, additional, Völk, Heinrich J., additional, Wagner, Stefan, additional, Watson, Jason John, additional, White, Richard, additional, Wierzcholska, Alicja, additional, Wong, Yu Wun, additional, Yassin, Hend Mahmoud, additional, Yusafzai, Anke, additional, Zacharias, Michael, additional, Zanin, Roberta, additional, Zargaryan, Davit, additional, Zdziarski, Andrzej, additional, Zech, Andreas, additional, Zhu, Sylvia, additional, Zmija, Andreas, additional, Zouari, Samuel, additional, and Żywucka, Natalia, additional
Published: 2021
Full Text: View/download PDF

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

Author: Zhu, Sylvia Jiechen, primary, Murach, Thomas, additional, Ohm, Stefan, additional, Fuessling, Matthias, additional, Krack, Fabian, additional, Mosshammer, Klemens, additional, lindemann, rico, additional, Lukas Holch, Tim, additional, and De Naurois, Mathieu, additional
Published: 2021
Full Text: View/download PDF

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

Author: Ashkar, Halim, primary, Zhu, Sylvia, additional, Brun, Francois, additional, Füßling, Matthias, additional, Hoischen, Clemens, additional, Konno, Ruslan, additional, Ohm, Stefan, additional, Prokoph, Heike, additional, Reichherzer, Patrick, additional, Schüssler, Fabian, additional, Seglar Arroyo, Monica, additional, and J Zhu, Sylvia, additional
Published: 2021
Full Text: View/download PDF

40. The H.E.S.S. gravitational wave rapid follow-up program

Author: Ashkar, Halim, primary, Brun, Francois, additional, Füßling, Matthias, additional, Hoischen, Clemens, additional, Ohm, Stefan, additional, Prokoph, Heike, additional, Reichherzer, Patrick, additional, Schüssler, Fabian, additional, and Seglar-Arroyo, Monica, additional
Published: 2021
Full Text: View/download PDF

41. Constraining the magnetic field in the EM170817 ejecta with H.E.S.S. observations

Author: Ohm, Stefan and HESS
Subjects: Physics, Neutron star, Jet (fluid), Astrophysics::High Energy Astrophysical Phenomena, r-process, Context (language use), Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Kilonova, Light curve, Ejecta, Astrophysics::Galaxy Astrophysics, Magnetic field
Abstract: 36th International Cosmic Ray Conference, Madison, USA, 24 Jul 2019 - 1 Aug 2019; PoS(ICRC2019)756 (2019)., The detection of the first electromagnetic counterpart to the binaryneutron star merger remnant GW170817 established the connectionbetween short gamma-ray bursts and binary neutron star mergers aswell as it confirmed the forging of heavy elements in the ejecta (a socalledkilonova) via the r process. The brightening of non-thermal radioand X-ray emission, however, came with some surprise and lastedmore than 100 days. Current theoretical models attempt to explain thelight curve as either originating from a relativistic off-axis jet, or akilonova-like outflow. Combining the VLA and Chandra measurementswith observations in the GeV - TeV domain, can help to break theambiguity between energy in non-thermal electrons and magnetic fieldof the emission region, almost independent of the assumed origin ofthe emission. Here we report for the first time on deep H.E.S.S.observations of EM170817 between 120 and 270 days after the binaryneutron star merger with the full H.E.S.S. array of telescopes as wellas on updated prompt (
Published: 2019
Full Text: View/download PDF

42. Towards a 3D likelihood analysis invery-high-energyγ-ray astronomy:the case of H.E.S.S

Author: Mohrmann∗, Lars, Nakashima, Kaori, Specovius, Andreas, Tiziani, Domenico, StefanFunk, Eldik, Christopher Van, and Ohm, Stefan
Abstract: 36th International Cosmic Ray Conference, Madison, USA, 24 Jul 2019 - 1 Aug 2019; PoS(ICRC2019)747 (2019)., The estimation of the residual background due to cosmic ray-induced air showers represents akey element of every analysis of Imaging Atmospheric Cherenkov Telescope (IACT) data. Inthe past, most techniques have relied on a measurement of the background in supposedly sourcefreeregions within the observed field of view. However, this approach is problematic in regionswith many (potentially overlapping) g-ray sources or large-scale diffuse g-ray emission, like e.g.the Galactic Plane. For these cases, a template-based 3D likelihood analysis might be superior.In this approach, a spectro-morphological model template, consisting of one or multiple sourcecomponents and a background component, is fit to the data, resulting in a complete spectral andspatial description of the field of view. In this contribution, we present our efforts to establish a3D likelihood analysis for data taken with the H.E.S.S. system of IACTs, using the open-sourceanalysis packages ctools and Gammapy. In particular, we focus on the development of a templatemodel for the cosmic ray-induced background – a major challenge in such an approach – fromarchival H.E.S.S. data. We characterise the obtained model and demonstrate its application usingpublicly available H.E.S.S. data. The validation of this analysis approach on experimental dataalso constitutes an important step towards the analysis of data from the upcoming CherenkovTelescope Array (CTA).
Published: 2019
Full Text: View/download PDF

43. Towards a 3D likelihood analysis in very-high-energy $\gamma$-ray astronomy: the case of H.E.S.S.

Author: Mohrmann, Lars, primary, Nakashima, Kaori, additional, Specovius, Andreas, additional, Tiziani, Domenico, additional, Funk, Stefan, additional, van Eldik, Christopher, additional, and Ohm, Stefan, additional
Published: 2019
Full Text: View/download PDF

44. Magnetic field estimates from the X-ray synchrotron emitting rims of the 30 Dor C superbubble and the implications for the nature of 30 Dor C’s TeV emission

Author: Kavanagh, Patrick J., primary, Vink, Jacco, additional, Sasaki, Manami, additional, Chu, You-Hua, additional, Filipović, Miroslav D., additional, Ohm, Stefan, additional, Haberl, Frank, additional, Manojlovic, Perica, additional, and Maggi, Pierre, additional
Published: 2019
Full Text: View/download PDF

45. Performance of the upgraded H.E.S.S. cameras

Author: Giavitto, Gianluca, primary, Bonnefoy, Simon, additional, Ashton, Terry, additional, Backes, Michael, additional, Balzer, Arnim, additional, Berge, David, additional, Brun, Francois, additional, Chaminade, Thomas, additional, Delagnes, Eric, additional, Fontaine, Gerard, additional, Fuessling, Matthias, additional, Giebels, Berrie, additional, Glicenstein, Jean-Francois, additional, Gräber, Tobias, additional, Hinton, Jim, additional, Jahnke, Albert, additional, Klepser, Stefan, additional, Kossatz, Marko, additional, Kretzschmann, Axel, additional, Lefranc, Valentin, additional, Leich, Holger, additional, Lenain, Jean-Philippe, additional, Lüdecke, Hartmut, additional, Lypova, Iryna, additional, Manigot, Pascal, additional, Marandon, Vincent, additional, Moulin, Emmanuel, additional, de Naurois, Mathieu, additional, Nayman, Patrick, additional, Ohm, Stefan, additional, Penno, Marek, additional, Ross, Duncan, additional, Salek, David, additional, Schade, Markus, additional, Schwab, Thomas, additional, Shiningayamwe, Kleopas, additional, Stegmann, Christian, additional, Steppa, Constantin, additional, Thornhill, Julian, additional, and Toussnel, Francois, additional
Published: 2018
Full Text: View/download PDF

46. A search for very high energy flares from the microquasars GRS 1915+105, Circinus X-1, and V4641 Sgr using contemporaneous H.E.S.S. and RXTE observations

Author: Abdallah, H., Abramowski, A., Aharonian, F., Ait Benkhali, F., Dickinson, H., Schüssler, F., Giavitto, Gianluca, Fuessling, Matthias, Haupt, Maria, Klepser, Stefan, Lypova, Iryna, Ohm, Stefan, Schulz, Anneli, Stycz, Kornelia, and Stegmann, Christian
Abstract: Astronomy and astrophysics 612, A10 (2016). doi:10.1051/0004-6361/201527773, Context. Microquasars are potential γ-$\gamma$ray emitters. Indications of transient episodes of $\gamma$-ray emission were recently reported in at least two systems: Cyg X-1 and Cyg X-3. The identification of additional $\gamma$-ray-emitting microquasars is required to better understand how $\gamma$-ray emission can be produced in these systems.Aim. Theoretical models have predicted very high-energy (VHE) $\gamma$-ray emission from microquasars during periods of transient outburst. Observations reported herein were undertaken with the objective of observing a broadband flaring event in the $\gamma$-ray and X-ray bands.Methods. Contemporaneous observations of three microquasars, GRS 1915+105, Circinus X-1, and V4641 Sgr, were obtained using the High Energy Spectroscopic System (H.E.S.S.) telescope array and the Rossi X-ray Timing Explorer (RXTE) satellite. X-ray analyses for each microquasar were performed and VHE $\gamma$-ray upper limits from contemporaneous H.E.S.S. observations were derived.Results. No significant $\gamma$-ray signal has been detected in any of the three systems. The integral $\gamma$-ray photon flux at the observational epochs is constrained to be $I$(>560 GeV) < 7.3 × $10^{−13} cm^{−2} s^{−1}$, $I$(>560 GeV ) < 1.2 × $10^{−12} cm^{−2} s^{−1}$, and $I$(>240 GeV) < 4.5 × $10^{−12} cm^{−2} s^{−1}$ for GRS 1915+105, Circinus X-1, and V4641 Sgr, respectively.Conclusions. The $\gamma$-ray upper limits obtained using H.E.S.S. are examined in the context of previous Cherenkov telescope observations of microquasars. The effect of intrinsic absorption is modelled for each target and found to have negligible impact on the flux of escaping $\gamma$-rays. When combined with the X-ray behaviour observed using RXTE, the derived results indicate that if detectable VHE $\gamma$-ray emission from microquasars is commonplace, then it is likely to be highly transient., Published by EDP Sciences, Les Ulis
Published: 2016
Full Text: View/download PDF

47. Recent results from the H.E.S.S. experiment

Author: Ohm, Stefan
Abstract: Winter School on Astroparticle Physics, Ooty, India, 21 Dec 2016 - 29 Dec 2016
Published: 2016
Full Text: View/download PDF

48. Hardware and software architecture of the upgraded H.E.S.S. cameras

Author: Klepser, Stefan, primary, Ashton, Terry, additional, Backes, Michael, additional, Balzer, Arnim, additional, Berge, David, additional, Bonnefoy, Simon, additional, Brun, Francois, additional, Chaminade, Thomas, additional, Delagnes, Eric, additional, Fontaine, Gerard, additional, Fuessling, Matthias, additional, Giavitto, Gianluca, additional, Giebels, Berrie, additional, Glicenstein, Jean-Francois, additional, Gräber, Tobias, additional, Hinton, Jim, additional, Jahnke, Albert, additional, Kossatz, Marko, additional, Kretzschmann, Axel, additional, Lefranc, Valentin, additional, Leich, Holger, additional, Lenain, Jean-Philippe, additional, Lüdecke, Hartmut, additional, Lypova, Iryna, additional, Manigot, Pascal, additional, Marandon, Vincent, additional, Moulin, Emmanuel, additional, De Naurois, Mathieu, additional, Nayman, Patrick, additional, Ohm, Stefan, additional, Penno, Marek, additional, Ross, Duncan, additional, Salek, David, additional, Schade, Markus, additional, Schwab, Thomas, additional, Shiningayamwe, Kleopas, additional, Stegmann, Christian, additional, Steppa, Constantin, additional, Thornhill, Julian, additional, and Toussnel, Francois, additional
Published: 2017
Full Text: View/download PDF

49. Statistical biases of spectral analysis with the ON-OFF likelihood statistic

Author: Jouvin, L., Lemièr, A., Terrier, R., Ohm, Stefan, Oya, I., van Eldik, C., H.E.S.S. Collaboration, AstroParticule et Cosmologie (APC (UMR_7164)), Observatoire de Paris, 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), H.E.S.S., 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), 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), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP)
Subjects: Astrophysics::High Energy Astrophysical Phenomena, Statistics, ddc:530, Spectral analysis, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Statistic, ComputingMilieux_MISCELLANEOUS, Mathematics, Statistical Biases
Abstract: International audience; Spectral extraction in data from ground-based gamma-ray observations is usually performed using the on-off likelihood statistic which is based on the profile likelihood technique. The latter is known to lead to inconsistent estimators in some situations. We present here a systematic Monte Carlo study of the distribution of fitted spectral parameters for typical observations with VHE (very high energy; >100GeV) observatories and show that in some conditions spectral extraction yields inconsistent estimators. We discuss some techniques to alleviate this effect and the impact on the search for spectral cutoffs in the very low statistic regime.
Published: 2015
Full Text: View/download PDF

50. The upgrade of the H.E.S.S. cameras

Author: Giavitto, Gianluca, primary, Ashton, Terry, additional, Balzer, Arnim, additional, Berge, David, additional, Brun, Francois, additional, Chaminade, Thomas, additional, Delagnes, Eric, additional, Fontaine, Gerard, additional, Füßling, Matthias, additional, Giebels, Berrie, additional, Glicenstein, Jean-Francois, additional, Gräber, Tobias, additional, Hinton, Jim, additional, Jahnke, Albert, additional, Klepser, Stefan, additional, Kossatz, Marko, additional, Kretzschmann, Axel, additional, Lefranc, Valentin, additional, Leich, Holger, additional, Lüdecke, Hartmut, additional, Lypova, Iryna, additional, Manigot, Pascal, additional, Marandon, Vincent, additional, Moulin, Emmanuel, additional, de Naurois, Mathieu, additional, Nayman, Patrick, additional, Ohm, Stefan, additional, Penno, Marek, additional, Ross, Duncan, additional, Salek, David, additional, Schade, Markus, additional, Schwab, Thomas, additional, Simoni, Rachel, additional, Stegmann, Christian, additional, Steppa, Constantin, additional, Thornhill, Julian, additional, and Toussnel, Francois, additional
Published: 2017
Full Text: View/download PDF

Catalog

Books, media, physical & digital resources

See catalog results

Searchworks

Select search scope, currently: Articles Catalog books, media & more in Jio Institute collections Articles journal articles & other e-resources

Search

Search Constraints

Refine your results

Search Limiters

Topic

Publication Year Range

Language

Publication Type

Journal

Database

Publisher

108 results on '"Ohm, Stefan"'

Search Results

Catalog

Select search scope, currently: Articles

Catalog

books, media & more in Jio Institute collections

Articles

journal articles & other e-resources