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arXiv · 1105.3482

Polarization and photometric observations of the gamma-ray blazar PG 1553+113

I. Andruchow·J. A. Combi·A. J. Muñoz-Arjonilla·G. E. Romero·S. A. Cellone·J. Martí
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Abstract

We present the results of an observational photo-polarimetry campaign of the blazar PG 1553+113 at optical wavelengths. The blazar was recently detected at very high energies (> 100 GeV) by the H.E.S.S and MAGIC gamma-ray Cherenkov telescopes. Our high-temporal resolution data show significant variations in the linear polarization percentage and position angle at inter-night time-scales, while at shorter (intra-night) time-scales both parameters varied less significantly, if at all. Changes in the polarization angle seem to be common in gamma-ray emitting blazars. Simultaneous differential photometry (through the B and R bands) shows no significant variability in the total optical flux. We provide B and R magnitudes, along with a finding chart, for a set of field stars suitable for differential photometry.

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I. Andruchow, J. A. Combi, A. J. Muñoz-Arjonilla, G. E. Romero, S. A. Cellone, J. Martí. 2011-05-17. Polarization and photometric observations of the gamma-ray blazar PG 1553+113. https://doi.org/10.1051/0004-6361/201016009

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