Very high energy gamma rays from the direction of Sagittarius A

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2004-10-01
Aharonian, F
Akhperjanian, AG
Aye, KM
Bazer-Bachi, AR
Beilicke, M
Benbow, W
Berge, D
Berghaus, P
Bernlohr, K
Bolz, O
Boisson, C
Borgmeier, C
Breitling, F
Brown, AM
Gordo, JB
Chadwick, PM
Chitnis, VR
Chounet, LM
Cornils, R
Costamante, L
Degrange, B
Djannati-Atai, A
Drury, LO
Ergin, Tülün
Espigat, P
Feinstein, F
Fleury, P
Fontaine, G
Funk, S
Gallant, Y
Giebels, B
Gillessen, S
Goret, P
Guy, J
Hadjichristidis, C
Hauser, M
Heinzelmann, G
Henri, G
Hermann, G
Hinton, JA
Hofmann, W
Holleran, M
Horns, D
de Jager, OC
Jung, I
Khelifi, B
Komin, N
Konopelko, A
Latham, IJ
Le Gallou, R
Lemoine, M
Lemiere, A
Leroy, N
Lohse, T
Marcowith, A
Masterson, C
McComb, TJL
de Naurois, M
Nolan, SJ
Noutsos, A
Orford, KJ
Osborne, JL
Ouchrif, M
Panter, M
Pelletier, G
Pita, S
Pohl, M
Puhlhofer, G
Punch, M
Raubenheimer, BC
Raue, M
Raux, J
Rayner, SM
Redondo, I
Reimer, A
Reimer, O
Ripken, J
Rivoal, M
Rob, L
Rolland, L
Rowell, G
Sahakian, V
Sauge, L
Schlenker, S
Schlickeiser, R
Schuster, C
Schwanke, U
Siewert, M
Sol, H
Steenkamp, R
Stegmann, C
Tavernet, JP
Theoret, CG
Tluczykont, M
van der Walt, DJ
Vasileiadis, G
Vincent, P
Visser, B
Volk, HJ
Wagner, SJ
We report the detection of a point-like source of very high energy (VHE) gamma-rays coincident within 1' of Sgr A* obtained with the HESS array of Cherenkov telescopes. The gamma-rays exhibit a power-law energy spectrum with a spectral index of -2.2+/-0.09+/-0.15 and a flux above the 165 GeV threshold of (1.82+/-0.22)x10(-7) m(-2) s(-1). The measured flux and spectrum differ substantially from recent results reported in particular by the CANGAROO collaboration.
ASTRONOMY & ASTROPHYSICS

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Citation Formats
F. Aharonian et al., “Very high energy gamma rays from the direction of Sagittarius A,” ASTRONOMY & ASTROPHYSICS, pp. 0–0, 2004, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/39609.