PKS 2005-489 at VHE: Four Years of Monitoring with HESS and Simultaneous Multi-wavelength Observations Auteur(s): Acero F., Bazer-Bachi A.R., Becherini Y., Boisson C., Bolmont J., Borrel V., Brun F., Brun P., Boutelier T., Charbonnier A., Chounet L.-M., Coignet G., Degrange B., Djannati-Ataı A., Dubois F., Dubus G., Espigat P., Farnier C., Feinstein F., Fiasson A., Fontaine G., Gallant Y., Gérard L., Giebels B., Glicenstein J.F., Goret P., Jacholkowska Agnieszka, Marcowith A., Mehault J., Vasileiadis G. (Article) Publié: Annual Review Of Astronomy And Astrophysics, vol. 511 p.A52 (2010) Texte intégral en Openaccess : Ref HAL: in2p3-00445182_v1 Ref Arxiv: 0911.2709 DOI: 10.1051/0004-6361/200913073 Ref. & Cit.: NASA ADS Exporter : BibTex | endNote 19 citations Résumé: VHE observations of PKS 2005-489 were made with HESS from 2004 through 2007, together with three simultaneous multi-wavelength campaigns performed with XMM-Newton and RXTE in 2004 and 2005. A strong VHE signal, ~17sigma total, is detected during the four years of HESS observations (90.3 hrs live time). The integral flux above the average analysis threshold of 400 GeV is ~3% of the Crab and varies weakly on time-scales from days to years. At X-ray energies the flux is observed to vary by more than an order of magnitude between 2004 and 2005. Strong changes in the X-ray spectrum (DeltaGamma~0.7) are also observed, which appear to be mirrored in the VHE band. The SED of PKS 2005-489, constructed for the first time with contemporaneous data on both humps, shows significant evolution. The large flux variations in the X-ray band, coupled with weak or no variations in the VHE band and a similar spectral behavior, suggest the emergence of a new, separate, harder emission component in September 2005. Commentaires: 13 pages, 11 figures. Astronomy and Astrophysics, in press. Minor typographical/text changes |