Optical flux behaviour of a sample of Fermi blazars
  Aims: We aim at investigating the time-behaviour of a sample of gamma-ray blazars. We present the results from a 13 month-long optical photometry monitoring campaign of the blazars PKS 0048-097, PKS 0754+100, HB89 0827+243, PKS 0851+202, PKS 1253-055, PKS1510-089, PKS 1749+096, PKS 2230+114 and PKS 2251+158. Methods: We analyse the variability of each object, focusing on different time-scales (long term, short term, and microvariability), in an attempt to achieve a statistical comparison of the results. Results: After applying a geometric model to explain the variability results, we found that it is possible that a slight change in the direction of the jet generates the variations detected in some objects during this campaign. 
E. J. Marchesini, I. Andruchow, S. A. Cellone, J. A. Combi, L.   Zibecchi, J. Mart\'i, G. E. Romero, A. J. Mu\~noz-Arjonilla...
astro-ph.GA astro-ph.HE