X-ray spectrum of the radio-loud quasar PKS 1217 + 023

Abstract

A study of the X-ray (0.1-10 keV) spectrum from the radio-loud quasar, PKS 1217 + 023 is presented. This quasar was observed with Exosat on two epochs in January 29 and May 14, 1984. The data were obtained from the Exosat archives. The soft (0.1-2 keV) and hard (2-10 keV) X-ray fluxes have displayed significant changes between the two observations. There is neither a detection of any significant low energy absorption within the quasar nor is there any evidence for the presence of soft X-ray excess. The energy indices, alpha, of the power law fits to the LE + ME data of January 29 and May 14 are 0.98+0.18/-0.14 and 0.82+0.12/-0.11 (error bars are with 90 percent confidence), respectively. The values of alpha are consistent with the values obtained from Ginga observations but larger than that obtained from Einstein data. A thermal bremsstrahlung model also provides a good fit to the X-ray data of PKS 1217 + 023.