PKS 0537−286

First detected at radio frequencies in 1975, PKS 0537−286 was observed at X-rays by the Einstein observatory. It was later studied by ASCA, ROSAT, XMM and subsequently Swift. These observations showed PKS 0537−286 as extremely luminous quasar ( Lx=1047 erg s−1 in the 0.1-2 keV range) with a particularly hard spectrum (r = 1 measured by Swift/BAT), which in the γ-ray band, it shows an energy flux of (1.44 ± 0.006) × 10−11 erg cm−2 s−1 in the fourth catalogue of Fermi-LAT active galactic nuclei. A weak iron K emission line and reflection features is also found in PKS 0537−286. Moreover, Sowards-Emmerd et al. (2004) identified the quasar as probable counterpart of the EGRET source 3EG J0531−2940. == Characteristics ==

PKS 0537−286 is the brightest blazar beyond z = 3.0. Moreover, in several occasions, γ-ray flares were observed when the daily flux was above 10−6 photon cm−2 s−1. This makes PKS 0537−286 the most distant γ-ray flaring blazar. The broad-band emission from PKS 0537−286 was successfully modelled within a one-zone synchrotron and external inverse Compton scenario where the excess in optical and ultraviolet bands was interpreted as emission from bright thermal accretion disc. Based on a study published in 2010, the black hole contains a 2 billion solar masses. == References ==