English

Radio and gamma-ray emission in faint BL Lacs

High Energy Astrophysical Phenomena 2013-06-05 v1 Cosmology and Nongalactic Astrophysics

Abstract

The advent of Fermi is changing our understanding on the radio and gamma-ray emission in Active Galactic Nuclei. In fact, contrary to previous campaigns, Fermi mission reveals that BL Lac objects are the most abundant emitters in gamma-ray band. However, since they are relatively weak sources, most of their parsec scale structure as their multifrequency properties are poorly understood and/or not systematically investigated. Our main goal is to analyse, using a multiwavelength approach, the nuclear properties of an homogeneous sample of 42 faint BL Lacs, selected, for the first time in literature, with no constraint on their radio and gamma-ray flux densities/emission. We began asking and obtaining new VLBA observations at 8 and 15 GHz for the whole sample. We derived fundamental parameters as radio flux densities, spectral index information, and parsec scale structure. Moreover, we investigated their gamma-ray emission properties using the 2LAT Fermi results. Here, we report our preliminary results on the radio and gamma-ray properties of this sample of faint BL Lacs. In the next future, we will complete the multiwavelength analysis.

Keywords

Cite

@article{arxiv.1306.0827,
  title  = {Radio and gamma-ray emission in faint BL Lacs},
  author = {E. Liuzzo and B. Boccardi and M. Giroletti and G. Giovannini},
  journal= {arXiv preprint arXiv:1306.0827},
  year   = {2013}
}

Comments

6 pages, 2 figures, to appear in 11th European VLBI Network Symposium, ed. P. Charlot et al., Bordeaux (France), October 9-12, 2012