The Nature of Close Companions of the BL Lacertae Objects 1ES 0502+675 and 1ES 1440+122

Bibcode
2004ApJ...613..747G
DOI
10.1086/423169
Giovannini, G.; Falomo, R.; Scarpa, R.; Treves, A.; Urry, C. M.
Bibliographical reference

The Astrophysical Journal, Volume 613, Issue 2, pp. 747-751.

Advertised on:
10
2004
Journal
The Astrophysical Journal
Number of authors
5
IAC number of authors
0
Citations
11
Refereed citations
11
Description
We report on deep radio images and optical spectroscopy of two BL Lac objects that have very close compact companions. The two targets, 1ES 0502+675 and 1ES 1440+122, were selected from the Hubble Space Telescope imaging survey of 110 BL Lacs as candidates for possible gravitational lensing. The new observations clearly demonstrate that the companion objects are not secondary images of the active nuclei but, in spite of the relatively low chance projection probability, foreground Galactic stars. Gravitational lensing appears to be unimportant to the BL Lac phenomenon. We discuss the radio properties of the BL Lac objects in the context of standard beaming models and show that they are as expected for beamed FR I radio galaxies.
Type
Refereed
Galaxies
BL Lacertae objects

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