Query : 2005A&A...442L..53P

2005A&A...442L..53P - Astronomy and Astrophysics, volume 442, L53-56 (2005/11-2)

XMM-Newton discovery of soft X-ray absorption in the high-z superluminous Blazar RBS 315.


Abstract (from CDS):

We present the analysis and the results of a 20ks XMM-Newton observation of the extremely X-ray loud (LX≃5x1047erg/s) flat-spectrum radio quasar RBS 315 at a redshift of 2.69. This EPIC observation has allowed us to strongly constrain the slope of the continuum (Γ=1.23±0.01) as well as to discover the presence of a sharp drop below ≃2keV in its spectrum. Such a flat photon index and the huge luminosity suggest that the X-ray emission is due to the low energy tail of the Comptonized spectrum, produced from plasma in a relativistic jet oriented close to our line of sight. Even though the hypothesis of a break in the continuum cannot be completely discarded as an explanation of the soft X-ray cutoff, the presence of intrinsic absorption appears more plausible. Spectral fits with cold (NHz=1.62+0.09–0.09x1022cm–2) and lukewarm (NHz=2.2+0.9–0.3x1022cm–2; ξ=15+38–12erg/cm2/s) absorbers are statistically indistinguishable. Remarkably, our results are very similar to those reported so far for other absorbed high-z Blazars observed by XMM-Newton. The existence of this ``homogeneous'' class of jet-dominated superluminous obscured QSOs at high z therefore could be important in the context of the formation and cosmological evolution of radio-loud objects.

Abstract Copyright:

Journal keyword(s): galaxies: active - quasar: general - X-ray: individual: RBS 315

Simbad objects: 3

goto Full paper

goto View the references in ADS

Number of rows : 3
N Identifier Otype ICRS (J2000)
ICRS (J2000)
Mag U Mag B Mag V Mag R Mag I Sp type #ref
1850 - 2024
1 QSO J0225+1846 Bla 02 25 04.66884683 +18 46 48.7668666   20.0 20.0 19.09   ~ 105 1
2 QSO J0525-3343 QSO 05 25 06.1749810960 -33 43 05.643939828     18.50 18.5   ~ 59 1
3 QSO B2126-15 Bla 21 29 12.17589329 -15 38 41.0419083   17.61 17.3 17.3   ~ 505 1

To bookmark this query, right click on this link: simbad:objects in 2005A&A...442L..53P and select 'bookmark this link' or equivalent in the popup menu