Spectrum and variability of the Galactic center VHE γ-ray source HESS J1745-290

Beitrag in einer Fachzeitschrift
(Originalarbeit)


Details zur Publikation

Autorinnen und Autoren: van Eldik C, Aharonian F, Akhperjanian AG, Anton G, De Almeida UB, Bazer-Bachi AR, Becherini Y, Behera B, Bernloehr K, Boisson C, Bochow A, Borrel V, Braun I, Brion E, Brucker J, Brun P, Buehler R, Bulik T, Buesching I, Boutelier T, Chadwick PM, Charbonnier A, Chaves RCG, Cheesebrough A, Chounet LM, Clapson AC, Coignet G, Dalton M, Daniel MK, Davids ID, Degrange B, Deil C, Dickinson HJ, Djannati-Atai A, Domainko W, Drury LO, Dubois F, Dubus G, Dyks J, Dyrda M, Egberts K, Emmanoulopoulos D, Espigat P, Farnier C, Feinstein F, Fiasson A, Foerster A, Fontaine G, Fuessling M, Gabici S, Gallant YA, Gerard L, Giebels B, Glicenstein JF, Glueck B, Goret P, Hauser D, Hauser M, Heinz S, Heinzelmann G, Henri G, Hermann G, Hinton JA, Hoffmann A, Hofmann W, Holleran M, Hoppe S, Horns D, Jacholkowska A, De Jager OC, Jung I, Katarzynski K, Katz U, Kaufmann S, Kendziorra E, Kerschhaggl M, Khangulyan D, Khelifi B, Keogh D, Komin N, Kosack K, Lamanna G, Lenain JP, Lohse T, Marandon V, Martin JM, Martineau-Huynh O, Marcowith A, Maurin D, Mccomb TJL, Medina MC, Moderski R, Moulin E, Naumann-Godo M, De Naurois M, Nedbal D, Nekrassov D, Niemiec J, Nolan SJ, Ohm S, Olive JF, Wilhelmi EDO, Orford KJ, Ostrowski M, Panter M, Arribas MP, Pedaletti G, Pelletier G, Petrucci PO, Pita S, Puehlhofer G, Punch M, Quirrenbach A, Raubenheimer BC, Raue M, Rayner SM, Renaud M, Rieger F, Ripken J, Rob L, Rolland L, Rosier-Lees S, Rowell G, Rudak B, Rulten CB, Ruppel J, Sahakian V, Santangelo A, Schlickeiser R, Schoeck FM, Schroeder R, Schwanke U, Schwarzburg S, Schwemmer S, Shalchi A, Skilton JL, Sol H, Spangler D, Stawarz L, Steenkamp R, Stegmann C, Superina G, Szostek A, Tam PH, Tavernet JP, Terrier R, Tibolla O, Van Eldik C, Vasileiadis G, Venter C, Venter L, Vialle JP, Vincent P, Vivier M, Voelk HJ, Volpe F, Wagner SJ, Ward M, Zdziarski AA, Zech A
Zeitschrift: Astronomy & Astrophysics
Jahr der Veröffentlichung: 2009
Band: 503
Heftnummer: 3
Seitenbereich: 817-825
ISSN: 0004-6361
Sprache: Englisch


Abstract

Aims. A detailed study of the spectrum and variability of the source HESS J1745-290 in the Galactic Center (GC) region using new data from the H.E.S.S. array of Cherenkov telescopes is presented. Flaring activity and quasi periodic oscillations (QPO) of HESS J1745-290 are investigated. Methods. The image analysis is performed with a combination of a semi-analytical shower model and the statistical moment-based Hillas technique. The spectrum and lightcurves of HESS J1745-290 are derived with a likelihood method based on a spectral shape hypothesis. Rayleigh tests and Fourier analysis of the H.E.S.S. GC signal are used to study the periodicity of the source. Results. With a three-fold increase in statistics compared to previous work, a deviation from a simple power law spectrum is detected for the first time. The measured energy spectrum over the three years 2004, 2005 and 2006 of data taking is compatible with both a power law spectrum with an exponential cut-off and a broken power law spectrum. The curvature of the energy spectrum is likely to be intrinsic to the photon source, as opposed to effects of interstellar absorption. The power law spectrum with an exponential cut-off is characterized by a photon index of 2.10 ± 0.04 ± 0.10 and a cut-off energy at 15.7 ± 3.4±2.5 TeV. The broken power law spectrum exhibits spectral indices of 2.02 ± 0.08 ± 0.10 and 2.63 ± 0.14 ± 0.10 with a break energy at 2.57 ± 0.19stat ± 0.44 TeV. No significant flux variation is found. Increases in the γ-ray flux of HESS J1745-290 by at least a factor of two would be required for a 3cr detection of a flare with time scales of an hour. Investigation of possible QPO activity at periods claimed to be detected in X-rays does not show any periodicities in the H.E.S.S. signal. © ESO 2009.


FAU-Autorinnen und Autoren / FAU-Herausgeberinnen und Herausgeber

Anton, Gisela Prof. Dr.
Lehrstuhl für Experimentalphysik (Teilchen- und Astroteilchenphysik)
Brucker, Julia Dr. rer. nat.
Lehrstuhl für Physik
Heinz, Sebastian
Lehrstuhl für Physik
Katz, Uli Prof. Dr.
Lehrstuhl für Experimentalphysik (Astroteilchenphysik)
van Eldik, Christopher Prof. Dr.
Professur für Experimentalphysik


Einrichtungen weiterer Autorinnen und Autoren

Centre CEA de Saclay (Essonne)
Dublin Institute for Advanced Studies (DIAS)
Durham University
Eberhard Karls Universität Tübingen
École Polytechnique - Université Paris-Saclay
Humboldt-Universität zu Berlin
Institute of Nuclear Physics PAN / Instytut Fizyki Jądrowej im. Henryka Niewodniczańskiego PAN
Institut national de physique nucléaire et de physique des particules (IN2P3)
Jagiellonian University / Uniwersytet Jagielloński (UJ)
Max-Planck-Institut für Kernphysik (MPIK) / Max Planck Institute for Nuclear Physics
Nicolaus Copernicus Astronomical Centre of the Polish Academy of Sciences
Nicolaus Copernicus University / Uniwersytet Mikołaja Kopernika w Toruniu (UMK)
Noordwes-Universiteit / North-West University
Ruhr-Universität Bochum (RUB)
Ruprecht-Karls-Universität Heidelberg
Universität Hamburg
Université Joseph Fourier (UJF Grenoble 1)
Université Toulouse III - Paul Sabatier
University of Adelaide
University of Leeds
University of Montpellier / Université Montpellier
University of Namibia (UNAM)
University of Paris 7 - Denis Diderot / Université Paris VII Denis Diderot
Univerzita Karlova v Praze / Charles University in Prague
Yerevan Physics Institute (YerPhI) / Երևանի Ֆիզիկայի Ինստիտուտ


Zitierweisen

APA:
van Eldik, C., Aharonian, F., Akhperjanian, A.G., Anton, G., De Almeida, U.B., Bazer-Bachi, A.R.,... Zech, A. (2009). Spectrum and variability of the Galactic center VHE γ-ray source HESS J1745-290. Astronomy & Astrophysics, 503(3), 817-825. https://dx.doi.org/10.1051/0004-6361/200811569

MLA:
van Eldik, Christopher, et al. "Spectrum and variability of the Galactic center VHE γ-ray source HESS J1745-290." Astronomy & Astrophysics 503.3 (2009): 817-825.

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Zuletzt aktualisiert 2018-27-10 um 14:50