[SEMINARI] A new sample of faint blazars, Franco Mantovani

[Enric Marco]

A new sample of faint blazars
Franco Mantovani
Istituto di Radioastronomia - INAF, Bologna, Italy

Seminari del departament d'Astronomia i Astrofísica
Dijous 04 novembre 2010
12:00

Resum
The available blazar samples were selected at relatively high limiting
flux densities in the radio and X-ray band. Those samples have small
sizes (30-50 objects) making it difficult to statistically derive
parameters related to beaming effects. Moreover, the estimate of those
parameters is based on bright and intrinsically luminous sources. A
deeper, larger sample of blazars has been constructed by Perlman et
al. (1998) and by Landt et al. (2001): the ``Deep X-ray Radio Blazar
Survey". The DXRBS sample is currently the faintest (down to ~ 50 mJy
at 5 GHz and power ~ 10^(24) W/Hz and largest blazar sample with
nearly complete optical identifications. We have built a complete
sample of 103 DXRBS sources selecting those with declination > -20
deg. It is expect that the objects in the DXRBS will be the
counterparts of gamma-ray sources detected by the Fermi gamma-ray
Observatory. After 1 year of Fermi observations, nearly 10% of the
DXRBS sources in our sample have already been detected. In this
presentation we will report on: 
- the structure of the sources observed so far with the European VLBI
Network at 6cm; 
- the results from Effelsberg 100-m telescope simultaneous multi-
frequency observations (at 11cm, 6cm, 3.6cm, 2.8cm) to obtain properly
measured spectral index, polarisation properties, and check for flux
density variability.

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Dr. Enric Marco
Departament d'Astronomia i Astrofísica
Facultat de Física
Universitat de València
C/  Dr. Moliner, 50
46100 Burjassot, Spain
Phone: (34)-96-354-3069
Fax:(34)-96-354-3084
enric.marco en uv.es
www.uv.es/marco
www.uv.es/aia2009
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