SDSS J102623.61+254259.5: the second most distant blazar at z = 5.3
Abstract
The radio-loud quasar SDSS J102623.61+254259.5, at a redshift z = 5.3, is one of the most distant radio-loud objects. Since its radio flux exceeds 100 mJy at a few GHz, it is also one of the most powerful radio-loud sources. We propose that this source is a blazar, i.e. we are seeing its jet at a small viewing angle. This claim is based on the spectral energy distribution of this source, and especially on its strong and hard X-ray spectrum, as seen by Swift, very typical of powerful blazars. Observations by the Gamma-Ray Burst Optical/Near-Infrared Detector (GROND) and by the Wide-field Infrared Survey Explorer (WISE) allow us to establish the thermal nature of the emission in the near-IR-optical band. Assuming that this is produced by a standard accretion disc, we derive that it emits a luminosity of Ld≃ 9 × 1046 erg s-1 and that the black hole has a mass between 2 and 5 billion solar masses. This poses interesting constraints on the mass function of heavy (>109 M⊙) black holes at high redshifts.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- October 2012
- DOI:
- 10.1111/j.1745-3933.2012.01332.x
- arXiv:
- arXiv:1208.3467
- Bibcode:
- 2012MNRAS.426L..91S
- Keywords:
-
- galaxies: active;
- quasars: general;
- quasars: individual: B2 1023+25;
- X-rays: general;
- Astrophysics - Cosmology and Nongalactic Astrophysics;
- Astrophysics - High Energy Astrophysical Phenomena
- E-Print:
- 5 pages, 3 figures. Accepted for publication in MNRAS