Skip to Main content Skip to Navigation
Journal articles

Simultaneous H.E.S.S. and Chandra observations of Sagittarius A* during an X-ray flare

F. Aharonian A.G. Akhperjanian U. Barres de Almeida A.R. Bazer-Bachi 1 Y. Becherini 2 B. Behera W. Benbow K. Bernlöhr C. Boisson 3 A. Bochow V. Borrel 1 I. Braun E. Brion 4 J. Brucker P. Brun 4 R. Bühler T. Bulik I. Büsching T. Boutelier 5 S. Carrigan P.M. Chadwick A. Charbonnier 6 R.C.G. Chaves A. Cheesebrough L.-M. Chounet 7 A.C. Clapson G. Coignet 8 B. Degrange 7 C. Deil H.J. Dickinson A. Djannati-Ataï 9 W. Domainko L.O'C. Drury F. Dubois 8 G. Dubus 5 J. Dyks M. Dyrda K. Egberts D. Emmanoulopoulos P. Espigat 2 C. Farnier 10 F. Feinstein 10 A. Fiasson 10 A. Förster G. Fontaine 7 M. Füsling S. Gabici Y.A. Gallant 10 L. Gérard 2 B. Giebels 7 J.F. Glicenstein 4 B. Glück P. Goret 4 C. Hadjichristidis D. Hauser M. Hauser S. Heinz G. Heinzelmann G. Henri 5 G. Hermann J.A. Hinton A. Hoffmann W. Hofmann M. Holleran S. Hoppe D. Horns A. Jacholkowska 6 O.C. de Jager I. Jung K. Katarzy'Nski S. Kaufmann E. Kendziorra M. Kerschhaggl D. Khangulyan B. Khélifi 7 D. Keogh Nu. Komin 4 K. Kosack G. Lamanna 8 J.-P. Lenain 3 T. Lohse V. Marandon 2 J.M. Martin 3 O. Martineau-Huynh 6 A. Marcowith 10 D. Maurin 6 T.J.L. Mccomb M.C. Medina 3 R. Moderski Emmanuel Moulin 4 M. Naumann-Godo 7 M. de Naurois 6 D. Nedbal D. Nekrassov J. Niemiec S.J. Nolan S. Ohm J.-F. Olive 1 E. de Oña Wilhelmi 2 K.J. Orford J.L. Osborne M. Ostrowski M. Panter G. Pedaletti G. Pelletier 5 P.-O. Petrucci 5 S. Pita 2 G. Pühlhofer M. Punch 2 A. Quirrenbach B.C. Raubenheimer M. Raue S.M. Rayner M. Renaud F. Rieger J. Ripken L. Rob S. Rosier-Lees 8 G. Rowell B. Rudak C.B. Rulten J. Ruppel V. Sahakian A. Santangelo R. Schlickeiser F.M. Schöck R. Schröder U. Schwanke S. Schwarzburg S. Schwemmer A. Shalchi J.L. Skilton H. Sol 3 D. Spangler L. Stawarz R. Steenkamp C. Stegmann G. Superina 7 P.H. Tam J.-P. Tavernet 6 R. Terrier 2 O. Tibolla C. van Eldik G. Vasileiadis 10 C. Venter J.P. Vialle 8 P. Vincent 6 M. Vivier 4 H.J. Völk F. Volpe 7 S.J. Wagner M. Ward A.A. Zdziarski A. Zech 3
Abstract : The rapidly varying (~10 minute timescale) non-thermal X-ray emission observed from Sgr A* implies that particle acceleration is occuring close to the event horizon of the supermassive black hole. The TeV gamma-ray source HESS J1745-290 is coincident with Sgr A* and may be closely related to its X-ray emission. Simultaneous X-ray and TeV observations are required to elucidate the relationship between these objects. We report on joint H.E.S.S./Chandra observations performed in July 2005, during which an X-ray flare was detected. Despite a factor of 9 increase in the X-ray flux of Sgr A*, no evidence is found for an increase in the TeV gamma-ray flux from this region. We find that an increase in the gamma-ray flux of a factor of 2 or greater can be excluded at a confidence level of 99%. This finding disfavours scenarios in which the keV and TeV emission are associated with the same population of accelerated particles and in which the bulk of the gamma-ray emission is produced within ~10^{14} cm (~100 R_S) of the supermassive black hole.
Complete list of metadatas

http://hal.in2p3.fr/in2p3-00348809
Contributor : Swarna Bassava <>
Submitted on : Monday, December 22, 2008 - 11:18:20 AM
Last modification on : Tuesday, November 17, 2020 - 2:36:03 PM

Links full text

Identifiers

Citation

F. Aharonian, A.G. Akhperjanian, U. Barres de Almeida, A.R. Bazer-Bachi, Y. Becherini, et al.. Simultaneous H.E.S.S. and Chandra observations of Sagittarius A* during an X-ray flare. Astronomy and Astrophysics - A&A, EDP Sciences, 2008, 492, pp.L25-L28. ⟨10.1051/0004-6361:200810912⟩. ⟨in2p3-00348809⟩

Share

Metrics

Record views

988