First X-ray spectrum of the most luminous quasar PKS 2126 - 158

Abstract

For the first time the detailed results of the spectral analysis of the X-ray (0.1 - 10 keV) spectrum of the luminous radio-loud quasar PKS 2126 - 158 are presented. Power law and fixed absorption model fits well with the spectrum. The parameters of this model suggest that this quasar is a flat spectrum source. Derived soft (0.1 - 2 keV) and hard (2 - 10 keV) X-ray luminosities of this quasar are (0.7 +/- 0.1) 10 exp 48 erg/s and (2.3 +/- 0.3) 10 exp 48 erg/s, respectively. No soft excess and low energy absorption have been detected in this source. Thermal bremsstrahlung model also fits well with the spectrum of PKS 2126 - 158 and the derived rest-frame temperature is 6.4 + 40 or -4 keV. This is the most luminous quasar which has been detected in the hard X-rays