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arXiv · 2304.03664

Multi-band optical variability of a newly discovered twelve blazars sample from 2013-2019

Miljana D. Jovanovic·Goran Damljanovic·Francois Taris·Alok C. Gupta·Gopal Bhatta
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Abstract

Here we present the first optical photometric monitoring results of a sample of twelve newly discovered blazars from the ICRF - Gaia CRF astrometric link. The observations were performed from April 2013 until August 2019 using eight telescopes located in Europe. For a robust test for the brightness and colour variability, we use Abbe criterion and F-test. Moreover, linear fittings are performed to investigate the relation in the colour-magnitude variations of the blazars. Variability was confirmed in the case of 10 sources; two sources, 1429+249 and 1556+335 seem to be possibly variable. Three sources (1034+574, 1722+119, and 1741+597) have displayed large amplitude brightness change of more than one magnitude. We found that the seven sources displayed bluer-when-brighter variations, and one source showed redder-when-brighter variations. We briefly explain the various AGN emission models which can explain our results.

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Miljana D. Jovanovic, Goran Damljanovic, Francois Taris, Alok C. Gupta, Gopal Bhatta. 2023-04-07. Multi-band optical variability of a newly discovered twelve blazars sample from 2013-2019. https://doi.org/10.1093/mnras%2Fstad904

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