Intranight optical variability of TeV blazars with parsec-scale jets dominated by slow-moving radio knots
Abstract
BL Lac objects detected at TeV energies preferentially belong to the subclass called 'high-frequency-peaked' BL Lacs (HBLs). Parsec-scale radio jets in these TeV-HBLs often show dominant, slow-moving radio knots that are at most mildly superluminal. We report the first systematic campaign to characterize the intranight optical variability (INOV) of TeV-HBLs using a representative sample of six such sources, all showing a fairly high degree of optical polarization. Our campaign consists of high-sensitivity monitoring of this sample in 24 sessions of more than 3 h duration each. For these TeV-HBLs, we find a striking lack of INOV and based on this, we discuss the importance of superluminal motion of the radio knots vis-a-vis the optical polarization, as the key diagnostic for INOV detection.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- September 2023
- DOI:
- 10.1093/mnrasl/slad077
- arXiv:
- arXiv:2306.06170
- Bibcode:
- 2023MNRAS.524L..66N
- Keywords:
-
- galaxies: active;
- BL Lacertae objects: general;
- galaxies: jets;
- galaxies: photometry;
- quasars: general;
- Astrophysics - High Energy Astrophysical Phenomena;
- Astrophysics - Astrophysics of Galaxies
- E-Print:
- accepted for publication in MNRAS letters