Extreme photo-polarimetric behaviour of the blazar AO 0235+164

Abstract

We present optical photo-polarimetric observations with high temporal resolution of the blazar AO 0235+164. Our data, the first to test the photo-polarimetric behaviour of this object at very short time-scales, show significant micro-variability in total flux, colour index, linear polarization degree, and position angle. Strong inter-night variations are also detected for these parameters. Although no correlation between colour index and total flux was found, our data seem to support the general bluer-when-brighter trend already known for this object. The polarization degree, in turn, shows no correlation with total flux, but a clear trend in the sense that colour index is redder (the spectrum is softer) when the measured polarization is higher.

arXiv commentAccepted by MNRAS (Letters), 5 pages

References in corpus (11)

• Optical and radio variability of the BL Lac object AO 0235+16: a possible 5-6 year periodicity
• Optical microvariability of EGRET blazars
• Helical jets in blazars. Interpretation of the multifrequency long-term variability of AO 0235+16
• Polarization microvariability of BL Lac objects
• Optical Linear Polarization of Late M- and L-Type Dwarfs
• Multifrequency variability of the blazar AO 0235+164. The WEBT campaign in 2004-2005 and long-term SED analysis
• Extremely violent optical microvariability in blazars: fact or fiction?
• The WEBT campaign to observe AO 0235+16 in the 2003-2004 observing season
• The binary black hole scenario for the BL Lacertae object AO 0235+16
• Microvariability in the optical polarization of 3C279
• Multiband optical polarimetry of the BL Lac object PKS 2155--304. Intranight and long term variability

Cited by in corpus (13)

• Multifrequency Photo-polarimetric WEBT Observation Campaign on the Blazar S5 0716+714: Source Microvariability and Search for Characteristic Timescales
• Detection of Polarimetric Variations Associated with the Shortest Time-Scale Variability in S5 0716$+$714
• Characterizing optical variability of OJ 287 in 2016 - 2017
• Minute-Scale Rapid Variability of Optical Polarization in Narrow-Line Seyfert 1 Galaxy: PMN J0948+0022
• Bayesian Approach to Find a Long-Term Trend in Erratic Polarization Variations Observed in Blazars
• Detection of a quasi-periodic oscillation in the optical light curve of the remarkable blazar AO 0235+164
• A statistical study of the optical spectral variability in gamma-ray blazars
• A comprehensive study on the variation phenomena of AO 0235+164
• Polarization and photometric observations of the gamma-ray blazar PG 1553+113
• Dense optical and near-infrared monitoring of CTA 102 during high state in 2012 with OISTER: Detection of intra-night "orphan polarized flux flare"
• Impact of seeing and host galaxy into the analysis of photo-polarimetric microvariability in blazars - Case study of the nearby blazars 1ES 1959+650 and HB89 2201+044
• Study of variability in long-term multiwavelength optical lightcurves of blazar AO 0235+164
• Dual-Beam Optical Linear Polarimetry from Southern Skies. Characterisation of CasPol for high precision polarimetry