Details

Autor(en) / Beteiligte

• AHARONIAN, F
• AKHPERJANIAN, A. G
• BOLZ, O
• BRAUN, I
• BREITLING, F
• BROWN, A. M
• BUSSONS GORDO, J
• CHADWICK, P. M
• CHOUNET, L.-M
• CORNILS, R
• COSTAMANTE, L
• DEGRANGE, B
• AYE, K.-M
• DJANNATI-ATAÏ, A
• DRURY, L. Oc
• DUBUS, G
• EMMANOULOPOULOS, D
• ESPIGAT, P
• FEINSTEIN, F
• FLEURY, P
• FONTAINE, G
• FUCHS, Y
• FUNK, S
• BAZER-BACHI, A. R
• GALLANT, Y. A
• GIEBELS, B
• GILLESSEN, S
• GLICENSTEIN, J. F
• GORET, P
• HADJICHRISTIDIS, C
• HAUSER, M
• HEINZELMANN, G
• HENRI, G
• HERMANN, G
• BEILICKE, M
• HINTON, J. A
• HOFMANN, W
• HOLLERAN, M
• HARNS, D
• DE JAGER, O. C
• JOHNSTON, S
• KHELIFI, B
• KIRK, J. G
• KOMIN, Nu
• KONOPELKO, A
• BENBOW, W
• LATHAM, I. J
• LE GALLOU, R
• LEMIERE, A
• LEMOINE-GOUMARD, M
• LEROY, N
• MARTINEAU-HUYNH, O
• LOHSE, T
• MARCOWITH, A
• MASTERSON, C
• MCCOMB, T. J. L
• BERGE, D
• BERGHAUS, P
• BERNLÖHR, K
• BOISSON, C

Titel

Discovery of the binary pulsar PSR B1259-63 in very-high-energy gamma rays around periastron with HESS

Ist Teil von

• Astronomy and astrophysics (Berlin), 2005-10, Vol.442 (1), p.1-10

Ort / Verlag

Les Ulis: EDP Sciences

Erscheinungsjahr

2005

Link zum Volltext

Quelle

EZB Electronic Journals Library

Beschreibungen/Notizen

• We report the discovery of very-high-energy (VHE) g-ray emission of the binary system PSR B 1259-63/SS 2883 of a radio pulsar orbiting a massive, luminous Be star in a highly eccentric orbit. The observations around the 2004 periastron passage of the pulsar were performed with the four 13 m Cherenkov telescopes of the HESS experiment, recently installed in Namibia and in full operation since December 2003. Between February and June 2004, a g-ray signal from the binary system was detected with a total significance above 13s. The flux was found to vary significantly on timescales of days which makes PSR B 1259-63 the first variable galactic source of VHE g-rays observed so far. Strong emission signals were observed in pre- and post-periastron phases with a flux minimum around periastron, followed by a gradual flux decrease in the months after. The measured time-averaged energy spectrum above a mean threshold energy of 380 GeV can be fitted by a simple power law F0(E/1 TeV)G with a photon index G = 2.7 c 0.2stat c 0.2sys and flux normalisation F0 = (1.3 c 0.1stat c 0.3sys) x 10-12 TeV-1 cm-2 s-1. This detection of VHE g-rays provides unambiguous evidence for particle acceleration to multi-TeV energies in the binary system. In combination with coeval observations of the X-ray synchrotron emission by the RXTE and INTEGRAL instruments, and assuming the VHE g-ray emission to be produced by the inverse Compton mechanism, the magnetic field strength can be directly estimated to be of the order of 1 G.