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A Sample of Low Redshift BL Lacs. I. The Radio Data

M. Giroletti·G. Giovannini·G. B. Taylor·R. Falomo
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Abstract

We present a new sample of 30 nearby (z<0.2) BL Lacs, selected to study the nuclear as well as the large scale properties of low power radio sources. In this first paper, we show and discuss new radio data taken with the VLA (19 objects at 1.4 GHz, either in A or C configuration, or both) as well as with the VLBA (15 sources at 5 GHz). On the kiloparsec scale, all objects exhibit a compact core and a variety of radio morphologies (jets, halos, secondary compact components). On the parsec scale, we find weak cores and a few short, one-sided, jets. From the jet/counter-jet ratio, core dominance, and synchrotron self Compton model we estimate the intrinsic orientation and velocity of the jets. The resulting properties of BL Lacs are similar to those of a parent population composed of FR I radio galaxies.

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M. Giroletti, G. Giovannini, G. B. Taylor, R. Falomo. 2004-06-09. A Sample of Low Redshift BL Lacs. I. The Radio Data. https://doi.org/10.1086/423231

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