Variable Hard X-Ray Emission from the Sgr B2 Molecular Cloud

R. Terrier; G. Ponti; G. Belanger; A. Decourchelle; V. Tatischeff; A. Goldwurm; G. Trap

HAL : in2p3-00650274, version 1

Fiche détaillée

Récupérer au format

Conference on the Galactic Center: A Window to the Nuclear Environment of Disk Galaxies, Shanghai : Chine (2009)

Variable Hard X-Ray Emission from the Sgr B2 Molecular Cloud

R. Terrier¹, G. Ponti², G. Belanger³, A. Decourchelle⁴, V. Tatischeff⁵, A. Goldwurm^{1, 4}, G. Trap^{1, 2, 4}

(2010)

The 4 million solar masses black hole at the Galactic centre (GC) is remarkably quiet today. The molecular cloud Sgr B2, among others, emits strong Fe K alpha photons as well as hard X-rays up to 100 keV. This has been interpreted as the result of the illumination of the cloud by a past high luminosity period of Sgr A*. This interpretation is still controversial since irradiation by subrelativistic cosmic rays might also account for the observed spectra. We present here the results of 7 years of INTEGRAL monitoring of Sgr B2 and show that its hard X-ray (20-60 keV) flux has decreased by nearly 40% during that period. This cannot be accounted for by cosmic ray interpretations and support the idea that Sgr A* was more active in the past and has been quiescent since about 100 years.

1 :	APC - AstroParticule et Cosmologie

2 :	Université Paris-Sud - Paris 11

3 :	LAPTH - Laboratoire d'Annecy-le-Vieux de Physique Théorique

4 :	IRFU - Institut de Recherches sur les lois Fondamentales de l'Univers (ex DAPNIA)

5 :	CSNSM - Centre de Spectrométrie Nucléaire et de Spectrométrie de Masse

équipe(s) de recherche : APC - AHE
CSNSM AN

Thème(s)

Physique/Astrophysique/Phénomènes cosmiques de haute energie

Planète et Univers/Astrophysique/Phénomènes cosmiques de haute energie

Mot(s)-clé(s) : GALACTIC-CENTER – LINE EMISSION – ORIGIN – VIEW – DISCOVERY


in2p3-00650274, version 1
http://hal.in2p3.fr/in2p3-00650274
oai:hal.in2p3.fr:in2p3-00650274
Contributeur : Christine Hadrossek <>
Soumis le : Vendredi 9 Décembre 2011, 16:11:18
Dernière modification le : Vendredi 30 Novembre 2012, 15:45:31