English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Context. The advent of Fermi is changing our understanding on the radio andgamma-ray emission in Active Galactic Nuclei. Contrary to pre-Fermi ideas, BLLac objects are found to be the most abundant emitters in the gamma-ray band.However, since they are relatively weak radio sources, most of theirparsec-scale structure and their multi-frequency properties are poorlyunderstood and/or have not been investigated in a systematically fashion. Aims.Our main goal is to analyze the radio and gamma-ray emission properties of asample of 42 BL Lacs selected, for the first time in the literature, with noconstraint on their radio and gamma-ray flux densities/emission. Methods.Thanks to new Very Long Baseline Array observations at 8 and 15 GHz for thewhole sample, we present here fundamental parameters such as radio fluxdensities, spectral index information, and parsec-scale structure. Moreover, wesearch for gamma-ray counterparts using data reported in the Second Catalog ofFermi Gamma-ray sources. Results. Parsec-scale radio emission is observed inthe majority of the sources at both frequencies. Gamma-ray counterparts arefound for 14/42 sources. Conclusions. The comparison between our results inradio and gamma-ray bands points out the presence of a large number of faint BLLacs showing "non classical" properties such as low source compactness, coredominance, no gamma-ray emission and steep radio spectral indexes. A deepermultiwavelength analysis will be needed.

Exploring the bulk of the BL Lac object population:1. parsec-scale radio structures