OISTER optical and near-infrared monitoring observations of peculiar radio-loud active galactic nucleus SDSS J110006.07+442144.3
Abstract
We present monitoring campaign observations at optical and near-infrared (NIR) wavelengths for a radio-loud active galactic nucleus (AGN) at z = 0.840, SDSS J110006.07+442144.3 (hereafter, J1100+4421), which was identified during a flare phase in late 2014 February. The campaigns consist of three intensive observing runs from the discovery to 2015 March, mostly within the scheme of the OISTER collaboration. Optical-NIR light curves and simultaneous spectral energy distributions (SEDs) are obtained. Our measurements show the strongest brightening in 2015 March. We found that the optical-NIR SEDs of J1100+4421 show an almost steady shape despite the large and rapid intranight variability. This constant SED shape is confirmed to extend to ∼5 μm in the observed frame using the archival WISE data. Given the lack of absorption lines and the steep power-law spectrum of αν ∼ -1.4, where f_{ν }∝ ν ^{α _{ν }}, synchrotron radiation by a relativistic jet with no or small contributions from the host galaxy and the accretion disk seems most plausible as an optical-NIR emission mechanism. The steep optical-NIR spectral shape and the large amplitude of variability are consistent with this object being a low νpeak jet-dominated AGN. In addition, sub-arcsecond resolution optical imaging data taken with Subaru Hyper Suprime-Cam does not show a clear extended component and the spatial scales are significantly smaller than the large extensions detected at radio wavelengths. The optical spectrum of a possible faint companion galaxy does not show any emission lines at the same redshift, and hence a merging hypothesis for this AGN-related activity is not supported by our observations.
- Publication:
-
Publications of the Astronomical Society of Japan
- Pub Date:
- October 2017
- DOI:
- 10.1093/pasj/psx075
- arXiv:
- arXiv:1707.05416
- Bibcode:
- 2017PASJ...69...82M
- Keywords:
-
- accretion;
- accretion disks;
- quasars: individual (SDSS J110006.07+442144.3);
- quasars: supermassive black holes;
- relativistic processes;
- Astrophysics - Astrophysics of Galaxies;
- Astrophysics - High Energy Astrophysical Phenomena
- E-Print:
- 22 pages, 7 figures, 2 tables. Accepted for publication in PASJ