|Title:||Long-term monitoring of the optical polarization in the TeV blazar PKS 2155-304|
|Date:||Thursday, 12 December 2013|
|Time:||11:00 - 12:00|
Blazars are radio-loud active galactic nuclei (AGN) that are characterized by intense and rapid variability across the electromagnetic spectrum. The observed emission from these objects is generally believed to originate from synchrotron processes in its relativistic jet. Multi-band polarimetric measurements are therefore an important tool to investigate the nature of the components that are responsible for the observed variability. In this work, a study of the temporal evolution of the optical polarization of the archetypal blazar PKS 2155-305 is presented. The source was monitored with the HIgh Speed Photo-POlarimter (HIPPO) of the SAAO and the SPOL imaging spectropolarimeter of the Steward Observatory between 2008 and 2013. Fluctuations in both the int ernight and intranight polarization is investigated. The frequency dependence of the polarization during an increased state of activity is also examined.