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1. Rapid Variability of Mrk 421 During Extreme Flaring as Seen Through the Eyes of XMM-Newton

Author

Gokus, A., Wilms, J., Kadler, M., Dorner, D., Nowak, M. A., Kreikenbohm, A., Leiter, K., Bretz, T., Schleicher, B., Markowitz, A. G., Pottschmidt, K., Mannheim, K., Kreykenbohm, I., Langejahn, M., McBride, F., Beuchert, T., Dauser, T., Kreter, M., Abhir, J., Baack, D., Balbo, M., Biland, A., Brand, K., Buss, J., Eisenberger, L., Elsaesser, D., Guenther, P., Hildebrand, D., Linhoff, M., Paravac, A., Rhode, W., Sliusar, V., Hasan, S., and Walter, R.

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

By studying the variability of blazars across the electromagnetic spectrum, it is possible to resolve the underlying processes responsible for rapid flux increases, so-called flares. We report on an extremely bright X-ray flare in the high-peaked BL Lacertae object Mrk 421 that occurred simultaneously with enhanced $\gamma$-ray activity detected at very high energies (VHE) by FACT on 2019 June 9. We triggered an observation with XMM-Newton, which observed the source quasi-continuously for 25 hours. We find that the source was in the brightest state ever observed using XMM-Newton, reaching a flux of $2.8\times10^{-9}$ erg cm$^{-2}$ s$^{-1}$ over an energy range of 0.3 - 10 keV. We perform a spectral and timing analysis to reveal the mechanisms of particle acceleration and to search for the shortest source-intrinsic time scales. Mrk 421 exhibits the typical harder-when-brighter behaviour throughout the observation and shows a clock-wise hysteresis pattern, which indicates that the cooling dominates over the acceleration process. While the X-ray emission in different sub-bands is highly correlated, we can exclude large time lags as the computed zDCFs are consistent with a zero lag. We find rapid variability on time scales of 1 ks for the 0.3 - 10 keV band and down to 300s in the hard X-ray band (4 - 10 keV). Taking these time scales into account, we discuss different models to explain the observed X-ray flare, and find that a plasmoid-dominated magnetic reconnection process is able to describe our observation best., Comment: 13 pages, 7 figures, accepted for publication in MNRAS

Published
2024

2. Multi-wavelength study of Mrk 421 during a TeV flare

Author

Gokus, A., Kreikenbohm, A., Leiter, K., Bretz, T., Dauser, T., Dorner, D., Elsaesser, D., Eppel, F., Hessdoerfer, J., Kadler, M., Kraus, A., Kreter, M., Kreykenbohm, I., Langejahn, M., Mannheim, K., Thalhammer, P., Wilms, J., Arbet-Engels, A., Baack, D., Balbo, M., Biland, A., Buss, J., Eisenberger, L., Hildebrand, D., Iotov, R., Kalenski, A., Mitchell, A., Neise, D., Noethe, M., Paravac, A., Rhode, W., Schleicher, B., Sliusar, V., and Walter, R.

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

The blazar Mrk 421 shows frequent, short flares in the TeV energy regime. Due to the fast nature of such episodes, we often fail to obtain sufficient simultaneous information about flux variations in several energy bands. To overcome this lack of multi-wavelength (MWL) coverage, especially for the pre- and post-flare periods, we have set up a monitoring program with the FACT telescope (TeV energies) and the Neil Gehrels Swift Observatory (X-rays). On 2019 June 9, Mrk 421 showed a TeV outburst reaching a flux level of more than two times the flux of the Crab Nebula at TeV energies. We acquired simultaneous data in the X-rays with additional observations by XMM-Newton and INTEGRAL. For the first time, we can study a TeV blazar in outburst taking advantage of highly sensitive X-ray data from XMM-Newton and INTEGRAL combined. Our dataset is complemented by pointed radio observations by Effelsberg at GHz frequencies. We present our first results, including the {\gamma}-ray and X-ray light curves, a timing analysis of the X-ray data obtained with XMM-Newton , as well as the radio spectra before, during and after the flare., Comment: 8 pages, 4 figures; Proceedings of the 37th International Cosmic Ray Conference (ICRC2021). 12-23 July, 2021. Berlin, Germany. Online at https://pos.sissa.it/395/

Published
2021
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3. Extended X-ray emission in PKS 1718$-$649

Author

Beuchert, T., Rodríguez-Ardila, A., Moss, V. A., Schulz, R., Kadler, M., Wilms, J., Angioni, R., Callingham, J. R., Gräfe, C., Krauß, F., Kreikenbohm, A., Langejahn, M., Leiter, K., Maccagni, F. M., Müller, C., Ojha, R., Ros, E., and Tingay, S. J.

Subjects
Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Astrophysics of Galaxies
Abstract

PKS 1718$-$649 is one of the closest and most comprehensively studied candidates of a young active galactic nucleus (AGN) that is still embedded in its optical host galaxy. The compact radio structure, with a maximal extent of a few parsecs, makes it a member of the group of compact symmetric objects (CSO). Its environment imposes a turnover of the radio synchrotron spectrum towards lower frequencies, also classifying PKS 1718$-$649 as gigahertz-peaked radio spectrum (GPS) source. Its close proximity has allowed the first detection of extended X-ray emission in a GPS/CSO source with Chandra that is for the most part unrelated to nuclear feedback. However, not much is known about the nature of this emission. By co-adding all archival Chandra data and complementing these datasets with the large effective area of XMM-Newton, we are able to study the detailed physics of the environment of PKS 1718$-$649. Not only can we confirm that the bulk of the $\lesssim$kiloparsec-scale environment emits in the soft X-rays, but we also identify the emitting gas to form a hot, collisionally ionized medium. While the feedback of the central AGN still seems to be constrained to the inner few parsecs, we argue that supernovae are capable of producing the observed large-scale X-ray emission at a rate inferred from its estimated star formation rate., Comment: 5 pages, 2 figures, 2 tables, accepted for publication by A&A

Published
2018
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4. Coincidence of a high-fluence blazar outburst with a PeV-energy neutrino event

Author

Kadler, M., Krauß, F., Mannheim, K., Ojha, R., Müller, C., Schulz, R., Anton, G., Baumgartner, W., Beuchert, T., Buson, S., Carpenter, B., Eberl, T., Edwards, P. G., Glawion, D. Eisenacher, Elsässer, D., Gehrels, N., Gräfe, C., Hase, H., Horiuchi, S., James, C. W., Kappes, A., Katz, U., Kreikenbohm, A., Kreter, M., Kreykenbohm, I., Langejahn, M., Leiter, K., Litzinger, E., Longo, F., Lovell, J. E. J., McEnery, J., Phillips, C., Plötz, C., Quick, J., Ros, E., Stecker, F. W., Steinbring, T., Stevens, J., Thompson, D. J., Trüstedt, J., Tzioumis, A. K., Wilms, J., and Zensus, J. A.

Subjects
Astrophysics - High Energy Astrophysical Phenomena, High Energy Physics - Phenomenology
Abstract

The discovery of extraterrestrial very-high-energy neutrinos by the IceCube collaboration has launched a quest for the identification of their astrophysical sources. Gamma-ray blazars have been predicted to yield a cumulative neutrino signal exceeding the atmospheric background above energies of 100 TeV, assuming that both the neutrinos and the gamma-ray photons are produced by accelerated protons in relativistic jets. Since the background spectrum falls steeply with increasing energy, the individual events with the clearest signature of being of an extraterrestrial origin are those at PeV energies. Inside the large positional-uncertainty fields of the first two PeV neutrinos detected by IceCube, the integrated emission of the blazar population has a sufficiently high electromagnetic flux to explain the detected IceCube events, but fluences of individual objects are too low to make an unambiguous source association. Here, we report that a major outburst of the blazar PKS B1424-418 occurred in temporal and positional coincidence with the third PeV-energy neutrino event (IC35) detected by IceCube. Based on an analysis of the full sample of gamma-ray blazars in the IC35 field and assuming a photo-hadronic emission model, we show that the long-term average gamma-ray emission of blazars as a class is in agreement with both the measured all-sky flux of PeV neutrinos and the spectral slope of the IceCube signal. The outburst of PKS B1424-418 has provided an energy output high enough to explain the observed PeV event, indicative of a direct physical association., Comment: Accepted for publication in Nature Physics on Mar 3rd, 2016 (arXiv version is the original submitted manuscript as per NatPhys regulations), 38 pages (including 10 pages of supplementary material), 3 figures

Published
2016
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5. ANTARES Constrains a Blazar Origin of Two IceCube PeV Neutrino Events

Author

ANTARES Collaboration, Adrián-Martínez, S., Albert, A., André, M., Anton, G., Ardid, M., Aubert, J. -J., Baret, B., Barrios, J., Basa, S., Bertin, V., Biagi, S., Bogazzi, C., Bormuth, R., Bou-Cabo, M., Bouwhuis, M. C., Bruijn, R., Brunner, J., Busto, J., Capone, A., Caramete, L., Carr, J., Chiarusi, T., Circella, M., Coniglione, R., Costantini, H., Coyle, P., Creusot, A., De Rosa, G., Dekeyser, I., Deschamps, A., De Bonis, G., Distefano, C., Donzaud, C., Dornic, D., Dorosti, Q., Drouhin, D., Dumas, A., Eberl, T., Enzenhöfer, A., Escoffier, S., Fehn, K., Felis, I., Fermani, P., Folger, F., Fusco, L. A., Galatà, S., Gay, P., Geißelsöder, S., Geyer, K., Giordano, V., Gleixner, A., Gómez-González, J. P., Gracia-Ruiz, R., Graf, K., Guillard, G., van Haren, H., Heijboer, A. J., Hello, Y., Hernández-Rey, J. J., Herrero, A., Hößl, J., Hofestädt, J., Hugon, C., James, C. W, de Jong, M., Kalekin, O., Katz, U., Kießling, D., Kooijman, P., Kouchner, A., Kulikovskiy, V., Lahmann, R., Lefèvre, D., Leonora, E., Loehner, H., Loucatos, S., Mangano, S., Marcelin, M., Margiotta, A., Martínez-Mora, J. A., Martini, S., Mathieu, A., Michael, T., Migliozzi, P., Neff, M., Nezri, E., Palioselitis, D., Păvălaş, G. E., Pellegrino, C., Perrina, C., Piattelli, P., Popa, V., Pradier, T., Racca, C., Riccobene, G., Richter, R., Roensch, K., Rostovtsev, A., Saldaña, M., Samtleben, D. F. E., Sánchez-Losa, A., Sanguineti, M., Sapienza, P., Schmid, J., Schnabel, J., Schulte, S., Schüssler, F., Seitz, T., Sieger, C., Spies, A., Spurio, M., Steijger, J. J. M., Stolarczyk, Th., Taiuti, M., Tamburini, C., Tayalati, Y., Trovato, A., Tselengidou, M., Tönnis, C., Vallage, B., Vallée, C., Van Elewyck, V., Visser, E., Vivolo, D., Wagner, S., de Wolf, E., Yepes, H., Zornoza, J. D., Zúñiga, J., Collaboration, TANAMI, Krauß, F., Kadler, M., Mannheim, K., Schulz, R., Trüstedt, J., Wilms, J., Ojha, R., Ros, E., Baumgartner, W., Beuchert, T., Blanchard, J., Bürkel, C., Carpenter, B., Edwards, P. G., Glawion, D. Eisenacher, Elsässer, D., Fritsch, U., Gehrels, N., Gräfe, C., Großberger, C., Hase, H., Horiuchi, S., Kappes, A., Kreikenbohm, A., Kreykenbohm, I., Langejahn, M., Leiter, K., Litzinger, E., Lovell, J. E. J., Müller, C., Phillips, C., Plötz, C., Quick, J., Steinbring, T., Stevens, J., Thompson, D. J., and Tzioumis, A. K.

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

The source(s) of the neutrino excess reported by the IceCube Collaboration is unknown. The TANAMI Collaboration recently reported on the multiwavelength emission of six bright, variable blazars which are positionally coincident with two of the most energetic IceCube events. Objects like these are prime candidates to be the source of the highest-energy cosmic rays, and thus of associated neutrino emission. We present an analysis of neutrino emission from the six blazars using observations with the ANTARES neutrino telescope.The standard methods of the ANTARES candidate list search are applied to six years of data to search for an excess of muons --- and hence their neutrino progenitors --- from the directions of the six blazars described by the TANAMI Collaboration, and which are possibly associated with two IceCube events. Monte Carlo simulations of the detector response to both signal and background particle fluxes are used to estimate the sensitivity of this analysis for different possible source neutrino spectra. A maximum-likelihood approach, using the reconstructed energies and arrival directions of through-going muons, is used to identify events with properties consistent with a blazar origin.Both blazars predicted to be the most neutrino-bright in the TANAMI sample (1653$-$329 and 1714$-$336) have a signal flux fitted by the likelihood analysis corresponding to approximately one event. This observation is consistent with the blazar-origin hypothesis of the IceCube event IC14 for a broad range of blazar spectra, although an atmospheric origin cannot be excluded. No ANTARES events are observed from any of the other four blazars, including the three associated with IceCube event IC20. This excludes at a 90\% confidence level the possibility that this event was produced by these blazars unless the neutrino spectrum is flatter than $-2.4$., Comment: 15 pages, 3 figures, 2 tables

Published
2015
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6. Rapid variability of Markarian 421 during extreme flaring as seen through the eyes of XMM–Newton

Author

Gokus, A, primary, Wilms, J, additional, Kadler, M, additional, Dorner, D, additional, Nowak, M A, additional, Kreikenbohm, A, additional, Leiter, K, additional, Bretz, T, additional, Schleicher, B, additional, Markowitz, A G, additional, Pottschmidt, K, additional, Mannheim, K, additional, Kreykenbohm, I, additional, Langejahn, M, additional, McBride, F, additional, Beuchert, T, additional, Dauser, T, additional, Kreter, M, additional, Abhir, J, additional, Baack, D, additional, Balbo, M, additional, Biland, A, additional, Brand, K, additional, Buss, J, additional, Eisenberger, L, additional, Elsaesser, D, additional, Günther, P, additional, Hildebrand, D, additional, Linhoff, M, additional, Paravac, A, additional, Rhode, W, additional, Sliusar, V, additional, Hasan, S, additional, and Walter, R, additional

Published
2024
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7. TANAMI Blazars in the IceCube PeV Neutrino Fields

Author

Krauß, F., Kadler, M., Mannheim, K., Schulz, R., Trüstedt, J, Wilms, J., Ojha, R., Ros, E., Anton, G., Baumgartner, W., Beuchert, T., Blanchard, J., Bürkel, C., Carpenter, B., Eberl, T., Edwards, P. G., Eisenacher, D., Elsässer, D., Fehn, K., Fritsch, U., Gehrels, N., Gräfe, C., Großberger, C., Hase, H., Horiuchi, S., James, C., Kappes, A., Katz, U., Kreikenbohm, A., Kreykenbohm, I., Langejahn, M., Leiter, K., Litzinger, E., Lovell, J. E. J., Müller, C., Phillips, C., Plötz, C., Quick, J., Steinbring, T., Stevens, J., Thompson, D. J., and Tzioumis, A. K.

Subjects
Astrophysics - High Energy Astrophysical Phenomena, High Energy Physics - Experiment, High Energy Physics - Phenomenology
Abstract

The IceCube Collaboration has announced the discovery of a neutrino flux in excess of the atmospheric background. Due to the steeply falling atmospheric background spectrum, events at PeV energies are most likely of extraterrestrial origin. We present the multiwavelength properties of the six radio brightest blazars positionally coincident with these events using contemporaneous data of the TANAMI blazar sample, including high-resolution images and spectral energy distributions. Assuming the X-ray to {\gamma}-ray emission originates in the photoproduction of pions by accelerated protons, the integrated predicted neutrino luminosity of these sources is large enough to explain the two detected PeV events., Comment: accepted to A&A, 2 June

Published
2014
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11. A robust variant of block Jacobi-Davidson for extracting a large number of eigenpairs: Application to grid-based real-space density functional theory.

Author

Lee, M., Leiter, K., Eisner, C., Breuer, A., and Wang, X.

Subjects
*JACOBI-Davidson method, *EIGENVALUES, *DENSITY functional theory, *FERMI-Dirac distribution, *EIGENVECTORS
Abstract

In this work, we investigate a block Jacobi-Davidson (J-D) variant suitable for sparse symmetric eigenproblems where a substantial number of extremal eigenvalues are desired (e.g., ground-state real-space quantum chemistry). Most J-D algorithm variations tend to slow down as the number of desired eigenpairs increases due to frequent orthogonalization against a growing list of solved eigenvectors. In our specification of block J-D, all of the steps of the algorithm are performed in clusters, including the linear solves, which allows us to greatly reduce computational effort with blocked matrix-vector multiplies. In addition, we move orthogonalization against locked eigenvectors and working eigenvectors outside of the inner loop but retain the single Ritz vector projection corresponding to the index of the correction vector. Furthermore, we minimize the computational effort by constraining the working subspace to the current vectors being updated and the latest set of corresponding correction vectors. Finally, we incorporate accuracy thresholds based on the precision required by the Fermi-Dirac distribution. The net result is a significant reduction in the computational effort against most previous block J-D implementations, especially as the number of wanted eigenpairs grows. We compare our approach with another robust implementation of block J-D (JDQMR) and the state-of-the-art Chebyshev filter subspace (CheFSI) method for various real-space density functional theory systems. Versus CheFSI, for first-row elements, our method yields competitive timings for valence-only systems and 4-6X speedups for all-electron systems with up to 10x reduced matrix-vector multiplies. For all-electron calculations on larger elements (e.g., gold) where thewanted spectrum is quite narrow compared to the full spectrum, we observe 60X speedup with 200X fewer matrix-vector multiples vs. [ABSTRACT FROM AUTHOR]

Published
2017
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12. ANTARES constrains a blazar origin of two IceCube PeV neutrino events

Author

Adrián Martínez, S., Albert, A., André, M., Anton, G., Ardid, M., Aubert, J. J., Baret, B., Barrios, J., Basa, S., Bertin, V., Biagi, S., Bogazzi, C., Bormuth, R., Bou Cabo, M., Bouwhuis, M. C., Bruijn, R., Brunner, J., Busto, J., Capone, Antonio, Caramete, L., Carr, J., Chiarusi, T., Circella, M., Coniglione, R., Core, L., Costantini, H., Coyle, P., Creusot, A., De Rosa, G., Dekeyser, I., Deschamps, A., DE BONIS, Giulia, Distefano, C., Donzaud, C., Dornic, D., Dorosti, Q., Drouhin, D., Dumas, A., Eberl, T., Enzenhöfer, A., Escoffier, S., Fehn, K., Felis, I., Fermani, Paolo, Folger, F., Fusco, L. A., Galatà, S., Gay, P., Geißelsöder, S., Geyer, K., Giordano, V., Gleixner, A., Gřómez González, J. P., Graf, K., Guillard, G., van Haren, H., Heijboer, A. J., Hello, Y., Hernández Rey, J. J., Herold, B., Herrero, A., Hößl, J., Hofestädt, J., Hugon, C., James, C. W., de Jong, M., Kalekin, O., Katz, U., Kießling, D., Kooijman, P., Kouchner, A., Kulikovskiy, V., Lahmann, R., Lambard, E., Lambard, G., Lefèvre, D., Leonora, E., Loehner, H., Loucatos, S., Mangano, S., Marcelin, M., Margiotta, A., Martínez Mora, J. A., Martini, S., Mathieu, A., Michael, T., Migliozzi, P., Neff, M., Nezri, E., Palioselitis, D., Păvăląs, G. E., Pellegrino, C., Perrina, Chiara, Piattelli, P., Popa, V., Pradier, T., Racca, C., Riccobene, G., Richter, R., Roensch, K., Rostovtsev, A., Saldaña, M., Samtleben, D. F. E., Sánchez Losa, . A., Sanguineti, M., Sapienza, P., Schmid, J., Schnabel, J., Schulte, S., Schüssler, F., Seitz, T., Sieger, C., Spies, A., Spurio, M., Steijger, J. J. M., Stolarczyk, T. h., Taiuti, M., Tamburini, C., Tayalati, Y., Trovato, A., Vallage, B., Vallée, C., Van Elewyck, V., Visser, E., Vivolo, D., Wagner, S., de Wolf, E., Yatkin, K., Yepes, H., Zornoza, J. D., Zúñiga, J., Krauß, F., Kadler, M., Mannheim, . K., Schulz, R., Trüstedt, J., Wilms, J., Ojha, R., Ros, E., Baumgartner, W., Beuchert, T., Blanchard, J., Bürkel, C., Carpenter, B., Edwards, P. G., Eisenacher Glawion, D., Elsässer, D., Fritsch, U., Gehrels, N., Gräfe, C., Großberger, C., Hase, H., Horiuchi, S., Kappes, A., Kreikenbohm, A., Kreykenbohm, I., Langejahn, M., Leiter, K., Litzinger, E., Lovell, J. E. J., Müller, C., Phillips, C., Plötz, C., Quick, J., Steinbring, T., Stevens, J., Thompson, D. J., Tzioumis, A. K., Research unit Nuclear & Hadron Physics, Institut d’Investigació per a la Gestió Integrada de Zones Costaneres (IGIC), Universitat Politècnica de València (UPV), Groupe de Recherche en Physique des Hautes Energies (GRPHE), Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut Universitaire de Technologie de Colmar, Laboratory of Applied Bioacoustics (LAB-UPC), Universidad Polytecnica de Cataluña (UPC), Erlangen Centre for Astroparticle Physics (ECAP), Friedrich-Alexander Universität Erlangen-Nürnberg (FAU), Centre de Physique des Particules de Marseille (CPPM), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Aix Marseille Université (AMU), AstroParticule et Cosmologie (APC (UMR_7164)), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7), Laboratoire d'Astrophysique de Marseille (LAM), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), Laboratoire de Physique Corpusculaire - Clermont-Ferrand (LPC), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut méditerranéen d'océanologie (MIO), Centre National de la Recherche Scientifique (CNRS)-Université de Toulon (UTLN)-Aix Marseille Université (AMU)-Institut de Recherche pour le Développement (IRD), Géoazur (GEOAZUR 7329), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud]), Université Paris-Sud - Paris 11 (UP11), Département de Physique des Particules (ex SPP) (DPP), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Institut Pluridisciplinaire Hubert Curien (IPHC), Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA), The ANTARES Collaboration, The TANAMI Collaboration, Institut Universitaire de Technologie de Colmar-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA)), 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), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS), Institut national des sciences de l'Univers (INSU - CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Centre National de la Recherche Scientifique (CNRS)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), KM3NeT (IHEF, IoP, FNWI), Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-IUT de Colmar, Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA)), Aix Marseille Université (AMU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, 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 de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud]), Département de Physique des Particules (ex SPP) (DPhP), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Adrián Martínez, S., Albert, A., André, M., Anton, G., Ardid, M., Aubert, J. J., Baret, B., Barrios, J., Basa, S., Bertin, V., Biagi, S., Bogazzi, C., Bormuth, R., Bou Cabo, M., Bouwhuis, M. C., Bruijn, R., Brunner, J., Busto, J., Capone, A., Caramete, L., Carr, J., Chiarusi, T., Circella, M., Coniglione, R., Costantini, H., Coyle, P., Creusot, A., DE ROSA, Gianfranca, Dekeyser, I., Deschamps, A., De Bonis, G., Distefano, C., Donzaud, C., Dornic, D., Dorosti, Q., Drouhin, D., Dumas, A., Eberl, T., Enzenhöfer, A., Escoffier, S., Fehn, K., Felis, I., Fermani, P., Folger, F., Fusco, L. A., Galatà, S., Gay, P., Geißelsöder, S., Geyer, K., Giordano, V., Gleixner, A., Gómez González, J. P., Gracia Ruiz, R., Graf, K., van Haren, H., Heijboer, A. J., Hello, Y., Hernández Rey, J. J., Herrero, A., Hößl, J., Hofestädt, J., Hugon, C., W. James, C., de Jong, M., Kalekin, O., Katz, U., Kießling, D., Kooijman, P., Kouchner, A., Kulikovskiy, V., Lahmann, R., Lattuada, D., Lefèvre, D., Leonora, E., Loehner, H., Loucatos, S., Mangano, S., Marcelin, M., Margiotta, A., Martínez Mora, J. A., Martini, S., Mathieu, A., Michael, T., Migliozzi, P., Neff, M., Nezri, E., Palioselitis, D., Păvălaş, G. E., Perrina, C., Piattelli, P., Popa, V., Pradier, T., Racca, C., Riccobene, G., Richter, R., Roensch, K., Rostovtsev, A., Saldaña, M., Samtleben, D. F. E., Sánchez Losa, A., Sanguineti, M., Sapienza, P., Schmid, J., Schnabel, J., Schulte, S., Schüssler, F., Seitz, T., Sieger, C., Spies, A., Spurio, M., Steijger, J. J. M., Stolarczyk, T. h., Taiuti, M., Tamburini, C., Tayalati, Y., Trovato, A., Tselengidou, M., Tönnis, C., Vallage, B., Vallée, C., Van Elewyck, V., Visser, E., Vivolo, Daniele, Wagner, S., de Wolf, E., Yepes, H., Zornoza, J. D., Zúñiga, J., Krauß, F., Kadler, M., Mannheim, K., Schulz, R., Trüstedt, J., Wilms, J., Ojha, R., Ros, E., Baumgartner, W., Beuchert, T., Blanchard, J., Bürkel, C., Carpenter, B., Edwards, P. G., Eisenacher Glawion, D., Elsässer, D., Fritsch, U., Gehrels, N., Gräfe, C., Großberger, C., Hase, H., Horiuchi, S., Kappes, A., Kreikenbohm, A., Kreykenbohm, I., Langejahn, M., Leiter, K., Litzinger, E., Lovell, J. E. J., Müller, C., Phillips, C., Plötz, C., Quick, J., Steinbring, T., Stevens, J., Thompson, D. J., Tzioumis, A. K., Adrian-Martinez, S, Albert, A, Andre, M, Anton, G, Ardid, M, Aubert, Jj, Baret, B, Barrios, J, Basa, S, Bertin, V, Biagi, S, Bogazzi, C, Bormuth, R, Bou-Cabo, M, Bouwhuis, Mc, Brujin, R, Brunner, J, Busto, J, Capone, A, Caramete, L, Cane, J, Chiarusim, T, Circella, M, Coniglione, R, Costantini, H, Coyle, P, Creusot, A, De Rosa, G, Dekeyser, I, Deschamps, A, De Bonis, G, Distefano, C, Donzaud, C, Dornic, D, Dorosti, Q, Drouhin, D, Dumas, A, Eberl, T, Enzenhofer, A, Escoffier, S, Fehn, K, Felis, I, Fermani, P, Folger, F, Fusco, La, Galata, S, Gay, P, Geisselsoder, S, Geyer, K, Giordano, V, Gleixner, A, Gomez-Gonzalez, Jp, Gracia-Ruiz, R, Graf, K, van Haren, H, Heijboer, Aj, Hello, Y, Hernandez-Rey, Jj, Herrero, A, Hossl, J, Hofestadt, J, Hugon, C, James, Cw, de Jong, M, Kalekin, O, Katz, U, Kiessling, D, Kooijman, P, Kouchner, A, Kulikovskiy, V, Lahmann, R, Lattuada, D, Lefevre, D, Leonora, E, Loehner, H, Loucatos, S, Mangano, S, Marcelin, M, Margiotta, A, Martinez-Mora, Ja, Martini, S, Mathieu, A, Michael, T, Migliozzi, P, Neff, M, Nezri, E, Palioselitis, D, Pavalas, Ge, Perrina, C, Piattelli, P, Popa, V, Pradier, T, Racca, C, Riccobene, G, Richter, R, Roensch, K, Rostovtsev, A, Saldana, M, Samtleben, Dfe, Sanchez-Losa, A, Sanguineti, M, Sapienza, P, Schmid, J, Schnabel, J, Schulte, S, Schussler, F, Seitz, T, Sieger, C, Spies, A, Spurio, M, Steijger, Jjm, Stolarczyk, T, Taiuti, M, Tamburini, C, Tayalati, Y, Trovato, A, Tselengidou, M, Tonnis, C, Vallage, B, Vallee, C, Van Elewyck, V, Visser, E, Vivolo, D, Wagner, S, de Wolf, E, Yepes, H, Zornoza, Jd, Zuniga, J, Krauss, F, Kadler, M, Mannheim, K, Schulz, R, Trustedt, J, Wilms, J, Ojha, R, Ros, E, Baumgartner, W, Beuchert, T, Blanchard, J, Burke, C, Carpenter, B, Edwards, Pg, Glawion, De, Elsasser, D, Fritsch, U, Gehrels, N, Grafe, C, Grossberger, C, Hase, H, Horiuchi, S, Kappes, A, Kreikenbohm, A, Kreykenbohm, I, Langejahn, M, Leiter, K, Litzinger, E, Lovell, Jej, Muller, C, Phillips, C, Plotz, C, Quick, J, Steinbring, T, Stevens, J, Thompson, Dj, Tzioumis, Ak, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Université de Strasbourg (UNISTRA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Adrián-Martínez, S, Aubert, J.-J., Bou-Cabo, M., Bouwhuis, M.C., De Rosa, G., Fusco, L.A., Gómez-González, J.P., Gracia-Ruiz, R., Van Haren, H., Heijboer, A.J., Hernández-Rey, J.J., James, C.W., De Jong, M., Martínez-Mora, J.A., Pəvəlaş, G.E., Samtleben, D.F.E., Sánchez-Losa, A., Steijger, J.J.M., Stolarczyk, Th., Vivolo, D., De Wolf, E., Zornoza, J.D., Edwards, P.G., Lovell, J.E.J., Thompson, D.J., Tzioumis, A.K., Centre Tecnològic de Vilanova i la Geltrú, Universitat Politècnica de Catalunya. LAB - Laboratori d'Aplicacions Bioacústiques, Adrian-Martinez, S., Andre, M., Aubert, J. -J., Enzenhofer, A., Galata, S., Geisselsoder, S., Gomez-Gonzalez, J. P., Hernandez-Rey, J. J., Hossl, J., Hofestadt, J., James, C. W., Kiessling, D., Lefevre, D., Martinez-Mora, J. A., Pevelas, G. E., Saldana, M., Sanchez-Losa, A., Schussler, F., Tonnis, C., Vallee, C., Zuniga, J., Krauss, F., Trustedt, J., Burkel, C., Elsasser, D., Grafe, C., Grossberger, C., Muller, C., and Plotz, C.

Subjects
Astrofísica, active [Galaxies], Astrophysics::High Energy Astrophysical Phenomena, Monte Carlo method, Flux, FOS: Physical sciences, Cosmic ray, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 7. Clean energy, 01 natural sciences, Spectral line, 0103 physical sciences, Neutrino, Galaxies: active, Neutrinos, Quasars: general, Neutrins, Blazar, 010303 astronomy & astrophysics, Physics, High Energy Astrophysical Phenomena (astro-ph.HE), Muon, Cosmologia, 010308 nuclear & particles physics, Física, Astronomy and Astrophysics, general [Quasars], Astronomy and Astrophysic, Neutrino astrophysics, Quasars general, Cosmology, neutrinos – galaxies: active – quasars: general, Space and Planetary Science, Galaxies active, Col·lisions (Física nuclear), Física::Astronomia i astrofísica [Àrees temàtiques de la UPC], FISICA APLICADA, Física nuclear, Astrophysics - High Energy Astrophysical Phenomena, MATEMATICA APLICADA, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Event (particle physics)
Abstract

Context. The source(s) of the neutrino excess reported by the IceCube Collaboration is unknown. The TANAMI Collaboration recently reported on the multiwavelength emission of six bright, variable blazars which are positionally coincident with two of the most energetic IceCube events. Objects like these are prime candidates to be the source of the highest-energy cosmic rays, and thus of associated neutrino emission. Aims. We present an analysis of neutrino emission from the six blazars using observations with the ANTARES neutrino telescope. Methods. The standard methods of the ANTARES candidate list search are applied to six years of data to search for an excess of muons and hence their neutrino progenitors from the directions of the six blazars described by the TANAMI Collaboration, and which are possibly associated with two IceCube events. Monte Carlo simulations of the detector response to both signal and background particle fluxes are used to estimate the sensitivity of this analysis for different possible source neutrino spectra. A maximum-likelihood approach, using the reconstructed energies and arrival directions of through-going muons, is used to identify events with properties consistent with a blazar origin. Results. Both blazars predicted to be the most neutrino-bright in the TANAMI sample (1653-329 and 1714-336) have a signal flux fitted by the likelihood analysis corresponding to approximately one event. This observation is consistent with the blazar-origin hypothesis of the IceCube event IC 14 for a broad range of blazar spectra, although an atmospheric origin cannot be excluded. No ANTARES events are observed from any of the other four blazars, including the three associated with IceCube event IC20. This excludes at a 90% confidence level the possibility that this event was produced by these blazars unless the neutrino spectrum is flatter than -2.4., The authors would like to thank A. Kappes for helpful discussions regarding the IceCube analysis. The ANTARES authors acknowledge the financial support of the funding agencies: Centre National de la Recherche Scientifique (CNRS), Commissariat a l'enegie atomique et aux energies alternatives (CEA), Commission Europeenne (FEDER fund and Marie Curie Program), Region Alsace (contrat CPER), Region Provence-Alpes-Cote d'Azur, Departement du Var and Ville de La Seyne-sur-Mer, France; Bundesministerium fur Bildung und Forschung (BMBF), Germany; Istituto Nazionale di Fisica Nucleare (INFN), Italy; Stichting voor Fundamenteel Onderzoek der Materie (FOM), Nederlandse organisatie voor Wetenschappelijk Onderzoek (NWO), the Netherlands; Council of the President of the Russian Federation for young scientists and leading scientific schools supporting grants, Russia; National Authority for Scientific Research (ANCS), Romania; Ministerio de Ciencia e Innovacion (MICINN), Prometeo of Generalitat Valenciana and MultiDark, Spain; Agence de l'Oriental and CNRST, Morocco. We also acknowledge the technical support of Ifremer, AIM and Foselev Marine for the sea operation and the CC-IN2P3 for the computing facilities. The TANAMI authors acknowledge support and partial funding by the Deutsche Forschungsgemeinschaft grant WI 1860-10/1 (TANAMI) and GRK 1147, Deutsches Zentrum fur Luft- und Raumfahrt grant 50 OR1311/50 OR1303/50 OR1401, the Spanish MINECO project AYA2012-38491-C02-01, the Generalitat Valenciana project PROMETEOII/2014/057, the COST MP0905 action "Black Holes in a Violent Universe" and the Helmholtz Alliance for Astroparticle Physics (HAP).

Published
2015
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13. Extended X-ray emission in PKS 1718−649

Author

Beuchert, T., primary, Rodríguez-Ardila, A., additional, Moss, V. A., additional, Schulz, R., additional, Kadler, M., additional, Wilms, J., additional, Angioni, R., additional, Callingham, J. R., additional, Gräfe, C., additional, Krauß, F., additional, Kreikenbohm, A., additional, Langejahn, M., additional, Leiter, K., additional, Maccagni, F. M., additional, Müller, C., additional, Ojha, R., additional, Ros, E., additional, and Tingay, S. J., additional

Published
2018
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14. Extended X-ray emission in PKS 1718-649

Author

Beuchert, T., Rodríguez-Ardila, A., Moss, V., Schulz, R., Kadler, M., Wilms, J., Angioni, R., Callingham, J., Gräfe, C., Krauß, F., Kreikenbohm, A., Langejahn, M., Leiter, K., Maccagni, F., Müller, C., Ojha, R., Ros, E., Tingay, Steven, Beuchert, T., Rodríguez-Ardila, A., Moss, V., Schulz, R., Kadler, M., Wilms, J., Angioni, R., Callingham, J., Gräfe, C., Krauß, F., Kreikenbohm, A., Langejahn, M., Leiter, K., Maccagni, F., Müller, C., Ojha, R., Ros, E., and Tingay, Steven

Abstract

© ESO 2018. PKS 1718-649 is one of the closest and most comprehensively studied candidates of a young active galactic nucleus (AGN) that is still embedded in its optical host galaxy. The compact radio structure, with a maximal extent of a few parsecs, makes it a member of the group of compact symmetric objects (CSO). Its environment imposes a turnover of the radio synchrotron spectrum towards lower frequencies, also classifying PKS 1718-649 as gigahertz-peaked radio spectrum (GPS) source. Its close proximity has allowed the first detection of extended X-ray emission in a GPS/CSO source with Chandra that is for the most part unrelated to nuclear feedback. However, not much is known about the nature of this emission. By co-adding all archival Chandra data and complementing these datasets with the large effective area of XMM-Newton, we are able to study the detailed physics of the environment of PKS 1718-649. Not only can we confirm that the bulk of the kiloparsec-scale environment emits in the soft X-rays, but we also identify the emitting gas to form a hot, collisionally ionized medium. While the feedback of the central AGN still seems to be constrained to the inner few parsecs, we argue that supernovae are capable of producing the observed large-scale X-ray emission at a rate inferred from its estimated star formation rate.

Published
2018

16. A computational framework for scale-bridging in multi-scale simulations

Author

Knap, J., Spear, C., Leiter, K., Becker, R., Powell, D., Laboratoire de Mathématiques et de leurs Applications [Pau] (LMAP), and Université de Pau et des Pays de l'Adour (UPPA)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[MATH.MATH-PR]Mathematics [math]/Probability [math.PR], surgical procedures, operative, TheoryofComputation_LOGICSANDMEANINGSOFPROGRAMS, [MATH.MATH-GT]Mathematics [math]/Geometric Topology [math.GT], education, [MATH.MATH-AP]Mathematics [math]/Analysis of PDEs [math.AP], [MATH]Mathematics [math], musculoskeletal system, ComputingMethodologies_ARTIFICIALINTELLIGENCE, human activities, ComputingMilieux_MISCELLANEOUS, health care economics and organizations, [MATH.MATH-NA]Mathematics [math]/Numerical Analysis [math.NA]
Abstract

ACL; International audience; no abstract

Published
2016
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17. X-Ray Characteristics of Water Megamaser Galaxies

Author

Leiter, K., primary, Kadler, M., additional, Wilms, J., additional, Braatz, J., additional, Grossberger, C., additional, Krauß, F., additional, Kreikenbohm, A., additional, Langejahn, M., additional, Litzinger, E., additional, Markowitz, A., additional, and Müller, C., additional

Published
2017
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18. Electron attachment to carbon dioxide clusters at very low electron energies.

Author

Stamatovic, A., Leiter, K., Ritter, W., Stephan, K., and Märk, T. D.

Subjects
*CARBON dioxide, *MOLECULAR beams, *MASS spectrometry, *COMPLEX ions
Abstract

Electron attachment to CO2 clusters formed by nozzle expansion was investigated in a crossed molecular-beam–electron-impact–mass spectrometer system. In addition to cluster ions previously observed at 3–4 eV electron energy we observe presently cluster ions produced at around zero electron energy. Some of these ions are likely produced by a less dissociative production mechanism allowing the probing of cluster beams with better reliability than previously. [ABSTRACT FROM AUTHOR]

Published
1985
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19. X-Ray Characteristics of Water Megamaser Galaxies

Author

Leiter, K., Kadler, M., Wilms, J., Braatz, J., Grossberger, C., Krauß, F., Kreikenbohm, A., Langejahn, M., Litzinger, E., Markowitz, A., Müller, C., Leiter, K., Kadler, M., Wilms, J., Braatz, J., Grossberger, C., Krauß, F., Kreikenbohm, A., Langejahn, M., Litzinger, E., Markowitz, A., and Müller, C.

Abstract

Contains fulltext : 197457.pdf (publisher's version ) (Closed access)

Published
2017

20. Welfare reform: advocacy and intervention in the health care setting

Author

Smith L, Todd J, Lawton E, and Leiter K

Subjects
Adult, medicine.medical_specialty, Economic growth, media_common.quotation_subject, Child Welfare, Patient Advocacy, Health Services Accessibility, Welfare reform, Hospitals, Urban, Health care, medicine, Humans, Child, Poverty, Socioeconomic status, health care economics and organizations, media_common, business.industry, Public health, Public Health, Environmental and Occupational Health, Public Assistance, Intervention (law), Health Care Reform, business, Welfare, Medicaid, Social Welfare, Research Article, Boston
Abstract

Welfare reform has drastically altered the lives of poor families in the US. In its wake, many former recipients are not receiving whatever transitional benefits and other safeguards to which they remain entitled under federal and state laws. Families are losing access to Medicaid and are not receiving the child care assistance or Food Stamps for which they continue to be eligible. Ill-served by stringent time limits and work requirements, lack of child care assistance, and lack of training and educational opportunities for the development of skills that will lead to better jobs, families need help to navigate the complexities of the new welfare system. Boston Medical Center's Department of Pediatrics has instituted a welfare screening project to educate families about their rights under welfare reform and assist them in advocating for themselves and their children.

Published
1999
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21. The TANAMI Multiwavelength Program: Dynamic spectral energy distributions of southern blazars⋆

Author

Krauß, F., Wilms, J., Kadler, M., Ojha, R., Schulz, R., Trüstedt, J., Edwards, P.G., Stevens, J., Ros, E., Baumgartner, W., Beuchert, T., Blanchard, J., Buson, S., Carpenter, B., Dauser, T., Falkner, S., Gehrels, N., Gräfe, C., Gulyaev, S., Hase, H., Horiuchi, S., Kreikenbohm, A., Kreykenbohm, I., Langejahn, M., Leiter, K., Lovell, J.E.J., Müller, C., Natusch, T., Nesci, R., Pursimo, T., Phillips, C., Plötz, C., Quick, J., Tzioumis, A.K., Weston, S., Krauß, F., Wilms, J., Kadler, M., Ojha, R., Schulz, R., Trüstedt, J., Edwards, P.G., Stevens, J., Ros, E., Baumgartner, W., Beuchert, T., Blanchard, J., Buson, S., Carpenter, B., Dauser, T., Falkner, S., Gehrels, N., Gräfe, C., Gulyaev, S., Hase, H., Horiuchi, S., Kreikenbohm, A., Kreykenbohm, I., Langejahn, M., Leiter, K., Lovell, J.E.J., Müller, C., Natusch, T., Nesci, R., Pursimo, T., Phillips, C., Plötz, C., Quick, J., Tzioumis, A.K., and Weston, S.

Abstract

Contains fulltext : 159678.pdf (preprint version ) (Open Access)

Published
2016

22. The TANAMI Multiwavelength Program: Dynamic spectral energy distributions of southern blazars

Author

Krauß, F., primary, Wilms, J., additional, Kadler, M., additional, Ojha, R., additional, Schulz, R., additional, Trüstedt, J., additional, Edwards, P. G., additional, Stevens, J., additional, Ros, E., additional, Baumgartner, W., additional, Beuchert, T., additional, Blanchard, J., additional, Buson, S., additional, Carpenter, B., additional, Dauser, T., additional, Falkner, S., additional, Gehrels, N., additional, Gräfe, C., additional, Gulyaev, S., additional, Hase, H., additional, Horiuchi, S., additional, Kreikenbohm, A., additional, Kreykenbohm, I., additional, Langejahn, M., additional, Leiter, K., additional, Lovell, J. E. J., additional, Müller, C., additional, Natusch, T., additional, Nesci, R., additional, Pursimo, T., additional, Phillips, C., additional, Plötz, C., additional, Quick, J., additional, Tzioumis, A. K., additional, and Weston, S., additional

Published
2016
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23. Coincidence of a high-fluence blazar outburst with a PeV-energy neutrino event

Author

Kadler, M., primary, Krauß, F., additional, Mannheim, K., additional, Ojha, R., additional, Müller, C., additional, Schulz, R., additional, Anton, G., additional, Baumgartner, W., additional, Beuchert, T., additional, Buson, S., additional, Carpenter, B., additional, Eberl, T., additional, Edwards, P. G., additional, Eisenacher Glawion, D., additional, Elsässer, D., additional, Gehrels, N., additional, Gräfe, C., additional, Gulyaev, S., additional, Hase, H., additional, Horiuchi, S., additional, James, C. W., additional, Kappes, A., additional, Katz, U., additional, Kreikenbohm, A., additional, Kreter, M., additional, Kreykenbohm, I., additional, Langejahn, M., additional, Leiter, K., additional, Litzinger, E., additional, Longo, F., additional, Lovell, J. E. J., additional, McEnery, J., additional, Natusch, T., additional, Phillips, C., additional, Plötz, C., additional, Quick, J., additional, Ros, E., additional, Stecker, F. W., additional, Steinbring, T., additional, Stevens, J., additional, Thompson, D. J., additional, Trüstedt, J., additional, Tzioumis, A. K., additional, Weston, S., additional, Wilms, J., additional, and Zensus, J. A., additional

Published
2016
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25. ANTARES constrains a blazar origin of two IceCube PeV neutrino events

Author

Adrian-Martinez, S., Albert, A., Andre, M., Anton, G., Ardid, M., Aubert, J., Baret, B., Barrios, J., Basa, S., Bertin, V., Biagi, S., Bogazzi, C., Bormuth, R., Bou-Cabo, M., Bouwhuis, M., Brujin, R., Brunner, J., Busto, J., Capone, A., Caramete, L., Cane, J., Chiarusim, T., Circella, M., Coniglione, R., Costantini, H., Coyle, P., Creusot, A., De Rosa, G., Dekeyser, I., Deschamps, A., De Bonis, G., Distefano, C., Donzaud, C., Dornic, D., Dorosti, Q., Drouhin, D., Dumas, A., Eberl, T., Enzenhoefer, A., Escoffier, S., Fehn, K., Felis, I., Fermani, P., Folger, F., Fusco, L., Galata, S., Gay, P., Geisselsoeder, S., Geyer, K., Giordano, V., Gleixner, A., Gomez-Gonzalez, J., Gracia-Ruiz, R., Graf, K., van Haren, H., Heijboer, A., Hello, Y., Hernandez-Rey, J., Herrero, A., Hoessl, J., Hofestaedt, J., Hugon, C., James, Clancy, de Jong, M., Kalekin, O., Katz, U., Kiessling, D., Kooijman, P., Kouchner, A., Kulikovskiy, V., Lahmann, R., Lattuada, D., Lefevre, D., Leonora, E., Loehner, H., Loucatos, S., Mangano, S., Marcelin, M., Margiotta, A., Martinez-Mora, J., Martini, S., Mathieu, A., Michael, T., Migliozzi, P., Neff, M., Nezri, E., Palioselitis, D., Pavalas, G., Perrina, C., Piattelli, P., Popa, V., Pradier, T., Racca, C., Riccobene, G., Richter, R., Roensch, K., Rostovtsev, A., Saldana, M., Samtleben, D., Sanchez-Losa, A., Sanguineti, M., Sapienza, P., Schmid, J., Schnabel, J., Schulte, S., Schuessler, F., Seitz, T., Sieger, C., Spies, A., Spurio, M., Steijger, J., Stolarczyk, T., Taiuti, M., Tamburini, C., Tayalati, Y., Trovato, A., Tselengidou, M., Toennis, C., Vallage, B., Vallee, C., Van Elewyck, V., Visser, E., Vivolo, D., Wagner, S., de Wolf, E., Yepes, H., Zornoza, J., Zuniga, J., Krauss, F., Kadler, M., Mannheim, K., Schulz, R., Truestedt, J., Wilms, J., Ojha, R., Ros, E., Baumgartner, W., Beuchert, T., Blanchard, J., Buerke, C., Carpenter, B., Edwards, P., Glawion, D., Elsaesser, D., Fritsch, U., Gehrels, N., Graefe, C., Grossberger, C., Hase, H., Horiuchi, S., Kappes, A., Kreikenbohm, A., Kreykenbohm, I., Langejahn, M., Leiter, K., Litzinger, E., Lovell, J., Mueller, C., Phillips, C., Ploetz, C., Quick, J., Steinbring, T., Stevens, J., Thompson, D., Tzioumis, A., Adrian-Martinez, S., Albert, A., Andre, M., Anton, G., Ardid, M., Aubert, J., Baret, B., Barrios, J., Basa, S., Bertin, V., Biagi, S., Bogazzi, C., Bormuth, R., Bou-Cabo, M., Bouwhuis, M., Brujin, R., Brunner, J., Busto, J., Capone, A., Caramete, L., Cane, J., Chiarusim, T., Circella, M., Coniglione, R., Costantini, H., Coyle, P., Creusot, A., De Rosa, G., Dekeyser, I., Deschamps, A., De Bonis, G., Distefano, C., Donzaud, C., Dornic, D., Dorosti, Q., Drouhin, D., Dumas, A., Eberl, T., Enzenhoefer, A., Escoffier, S., Fehn, K., Felis, I., Fermani, P., Folger, F., Fusco, L., Galata, S., Gay, P., Geisselsoeder, S., Geyer, K., Giordano, V., Gleixner, A., Gomez-Gonzalez, J., Gracia-Ruiz, R., Graf, K., van Haren, H., Heijboer, A., Hello, Y., Hernandez-Rey, J., Herrero, A., Hoessl, J., Hofestaedt, J., Hugon, C., James, Clancy, de Jong, M., Kalekin, O., Katz, U., Kiessling, D., Kooijman, P., Kouchner, A., Kulikovskiy, V., Lahmann, R., Lattuada, D., Lefevre, D., Leonora, E., Loehner, H., Loucatos, S., Mangano, S., Marcelin, M., Margiotta, A., Martinez-Mora, J., Martini, S., Mathieu, A., Michael, T., Migliozzi, P., Neff, M., Nezri, E., Palioselitis, D., Pavalas, G., Perrina, C., Piattelli, P., Popa, V., Pradier, T., Racca, C., Riccobene, G., Richter, R., Roensch, K., Rostovtsev, A., Saldana, M., Samtleben, D., Sanchez-Losa, A., Sanguineti, M., Sapienza, P., Schmid, J., Schnabel, J., Schulte, S., Schuessler, F., Seitz, T., Sieger, C., Spies, A., Spurio, M., Steijger, J., Stolarczyk, T., Taiuti, M., Tamburini, C., Tayalati, Y., Trovato, A., Tselengidou, M., Toennis, C., Vallage, B., Vallee, C., Van Elewyck, V., Visser, E., Vivolo, D., Wagner, S., de Wolf, E., Yepes, H., Zornoza, J., Zuniga, J., Krauss, F., Kadler, M., Mannheim, K., Schulz, R., Truestedt, J., Wilms, J., Ojha, R., Ros, E., Baumgartner, W., Beuchert, T., Blanchard, J., Buerke, C., Carpenter, B., Edwards, P., Glawion, D., Elsaesser, D., Fritsch, U., Gehrels, N., Graefe, C., Grossberger, C., Hase, H., Horiuchi, S., Kappes, A., Kreikenbohm, A., Kreykenbohm, I., Langejahn, M., Leiter, K., Litzinger, E., Lovell, J., Mueller, C., Phillips, C., Ploetz, C., Quick, J., Steinbring, T., Stevens, J., Thompson, D., and Tzioumis, A.

Published
2015

27. TANAMI blazars in the IceCube PeV-neutrino fields

Author

Krauss, F., Kadler, M., Mannheim, K., Schulz, R., Truestedt, J., Wilms, J., Ojha, R., Ros, E., Anton, G., Baumgartner, W., Beuchert, T., Blanchard, J., Buerkel, C., Carpenter, B., Eberl, T., Edwards, P., Eisenacher, D., Elsaesser, D., Fehn, K., Fritsch, U., Gehrels, N., Graefe, C., Grossberger, C., Hase, H., Horiuchi, S., James, Clancy, Kappes, A., Katz, U., Kreikenbohm, A., Kreykenbohm, I., Langejahn, M., Leiter, K., Litzinger, E., Lovell, J., Mueller, C., Phillips, C., Ploetz, C., Quick, J., Steinbring, T., Stevens, J., Thompson, D., Tzioumis, A., Krauss, F., Kadler, M., Mannheim, K., Schulz, R., Truestedt, J., Wilms, J., Ojha, R., Ros, E., Anton, G., Baumgartner, W., Beuchert, T., Blanchard, J., Buerkel, C., Carpenter, B., Eberl, T., Edwards, P., Eisenacher, D., Elsaesser, D., Fehn, K., Fritsch, U., Gehrels, N., Graefe, C., Grossberger, C., Hase, H., Horiuchi, S., James, Clancy, Kappes, A., Katz, U., Kreikenbohm, A., Kreykenbohm, I., Langejahn, M., Leiter, K., Litzinger, E., Lovell, J., Mueller, C., Phillips, C., Ploetz, C., Quick, J., Steinbring, T., Stevens, J., Thompson, D., and Tzioumis, A.

Published
2014

28. TANAMI blazars in the IceCube PeV-neutrino fields

Author

Krauß, F., primary, Kadler, M., additional, Mannheim, K., additional, Schulz, R., additional, Trüstedt, J., additional, Wilms, J., additional, Ojha, R., additional, Ros, E., additional, Anton, G., additional, Baumgartner, W., additional, Beuchert, T., additional, Blanchard, J., additional, Bürkel, C., additional, Carpenter, B., additional, Eberl, T., additional, Edwards, P. G., additional, Eisenacher, D., additional, Elsässer, D., additional, Fehn, K., additional, Fritsch, U., additional, Gehrels, N., additional, Gräfe, C., additional, Großberger, C., additional, Hase, H., additional, Horiuchi, S., additional, James, C., additional, Kappes, A., additional, Katz, U., additional, Kreikenbohm, A., additional, Kreykenbohm, I., additional, Langejahn, M., additional, Leiter, K., additional, Litzinger, E., additional, Lovell, J. E. J., additional, Müller, C., additional, Phillips, C., additional, Plötz, C., additional, Quick, J., additional, Steinbring, T., additional, Stevens, J., additional, Thompson, D. J., additional, and Tzioumis, A. K., additional

Published
2014
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29. Higher-Order Adaptive Finite-Element Methods for Kohn-Sham Density Functional Theory

Author

ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD, Motamarri, P, Nowak, M R, Leiter, K, Knap, J, Gavini, V, ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD, Motamarri, P, Nowak, M R, Leiter, K, Knap, J, and Gavini, V

Abstract

We present an efficient computational approach to perform real-space electronic structure calculations using an adaptive higher-order finite-element discretization of Kohn-Sham density-functional theory (DFT). To this end, we develop an a priori mesh adaption technique to construct a close to optimal finite-element discretization of the problem. We further propose an efficient solution strategy for solving the discrete eigenvalue problem by using spectral finite-elements in conjunction with Gauss-Lobatto quadrature, and a Chebyshev acceleration technique for computing the occupied eigenspace. Using the proposed solution procedure, we investigate the computational efficiency afforded by higher-order finite-element discretizations of the Kohn-Sham DFT problem. Our studies suggest that staggering computational savings--of the order of 1000-fold--can be realized, for both all-electron and pseudopotential calculations, by using higher-order finite-element discretizations. On all the benchmark systems studied, we observe diminishing returns in computational savings beyond the sixth-order for accuracies commensurate with chemical accuracy, suggesting that the hexic spectral-element may be an optimal choice for the finite-element discretization of the Kohn-Sham DFT problem. A comparative study of the computational efficiency of the proposed higher-order finite-element discretizations suggests that the performance of finite-element basis is competing with the plane-wave discretization for non-periodic pseudopotential calculations, and is comparable to the Gaussian basis for all-electron calculations. Further, we demonstrate the capability of the proposed approach to compute the electronic structure of materials systems containing a few thousand atoms using modest computational resources, and good scalability of the present implementation up to a few hundred processors., Preprint. Journal to be determined. Prepared in collaboration with Department of Mechanical Engineering, University of Michigan, Ann Arbor. Sponsored in part by AFOSR. The original document contains color images.

Published
2012

31. Applying Virtual Reality and Human Figure Modeling Tools to Explore Crew Manning Configurations of the U.S. Navy DDG Class Bridge

Author

ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD, Kozycki, R. W., Faughn, J. A., Leiter, K. L., Lockett, J. F., ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD, Kozycki, R. W., Faughn, J. A., Leiter, K. L., and Lockett, J. F.

Abstract

This report describes a portion of the modeling and simulation work performed by the Human Research and Engineering Directorate (HRED) of the U.S. Army Research Laboratory (ARL) in support of the manpower assessment technologies (MAT) project. For this effort, virtual reality (VR) technology and human figure modeling tools were applied to achieve some of the objectives of the MAT project. The discussion that follows in this report focuses on two software tools in particular, Jack(TM) and the Naval Postgraduate School Networking Software (NPSNET), and how each was used to demonstrate a proof of concept capability for examining crew manning configurations on U.S. Navy ships. In the future, U.S. Navy ships will need to be automated to a sufficient degree in order to realize significant manpower reductions in engineering, combat systems, ship support and Condition 3 watch-standing requirements. The use of VR technology and human figure modeling tools to graphically visualize concepts for Navy ships on the computer and to examine manning requirements before building physical prototypes, shows great promise in the future for saving time and reducing development cost.

Published
1997

34. Absolute partial and total electron ionization cross sections for CCl4 from threshold up to 180 eV

Author

Leiter, K., Stephan, K., Märk, E., and Märk, T. D.

Abstract

Electron impact ionization of carbon tetrachloride was studied as a function of electron energy from threshold up to 180 eV. A double-focusing mass spectrometer system in combination with an improved electron impact ion source was used, alleviating the problems of ion extraction from the source and the transmission of the extracted ions through the mass spectrometer system. Absolute partial ionization cross sections for the occurrence of CCl3+, CCl2+, CCl+, Cl2+, Cl+, C+, CCl32+, and CCl22+ have been determined. In addition, the total ionization cross-section function of CCl4 is reported and compared with theoretical predictions based on a classical binary encounter approximation. Using nth root extrapolation the following ionization energies of the doubly ionized fragment ions have been derived: AE(CCl32+)=30.4±0.3 eV; and AE (CCl22+)=31.8±0.3 eV. In accordance with theoretical predictions and previous results, no stable CCl4+ has been detected, however, metastable dissociation processes CCl4+ ? CCl3+ have been observed.

Published
1984
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36. VizieR Online Data Catalog: Dynamic SEDs of southern blazars - DSSB (Krauss+, 2016)

Author

Krauss, F., Wilms, J., Matthias Kadler, Ojha, R., Schulz, R., Trustedt, J., Edwards, P. G., Stevens, J., Ros, E., Baumgartner, W., Beuchert, T., Blanchard, J., Buson, S., Carpenter, B., Dauser, T., Falkner, S., Gehrels, N., Grafe, C., Gulyaev, S., Hase, H., Horiuchi, S., Kreikenbohm, A., Kreykenbohm, I., Langejahn, M., Leiter, K., Lovell, J. E. J., Muller, C., Natusch, T., Nesci, R., Pursimo, T., Phillips, C., Plotz, C., Quick, J., Tzioumis, A. K., and Weston, S.

44. Language Use and School Performance.

Author

Corsaro, William A., primary, Cicourel, Aaron V., additional, Jennings, K. H., additional, Jennings, S. H. M., additional, Leiter, K. C. W., additional, MacKay, Robert, additional, Mehan, Hugh, additional, and Roth, D. R., additional

Published
1976
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