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Optical-NIR variability of blazars on diverse timescales

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 نشر من قبل Alok C. Gupta Dr.
 تاريخ النشر 2015
  مجال البحث فيزياء
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To search for optical variability on a wide range of timescales, we have carried out photometric monitoring of 3C 454.3, 3C 279 and S5 0716+714. CCD magnitudes in B, V, R and I pass-bands were determined for $sim$ 7000 new optical observations from 114 nights made during 2011 - 2014, with an average length of $sim$ 4 h each, at seven optical telescopes. We measured multiband optical flux and colour variations on diverse timescales. We also investigated its spectral energy distribution using B, V, R, I, J and K pass-band data. We discuss possible physical causes of the observed spectral variability.



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