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VSOP monitoring of the compact BL Lac object AO 0235+164

S. Frey·L. I. Gurvits·D. C. Gabuzda·C. J. Salter·D. R. Altschuler·P. Perillat·M. F. Aller·H. D. Aller·H. Hirabayashi·M. M. Davis
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Abstract

In 1999, the highly compact and variable BL Lac object AO 0235+164 was identified as the highest brightness temperature active galactic nucleus observed with the VLBI Space Observatory Programme (VSOP), with T_B > 5.8 x 10^{13} K. The sub-milliarcsecond radio structure of this source has been studied with dual-frequency (1.6 and 5 GHz), polarization-sensitive VSOP observations during 2001 and 2002. Here we present the results of this monitoring campaign. At the time of these observations, the source was weakly polarized and characterized by a radio core that is clearly resolved on space-ground baselines.

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S. Frey, L. I. Gurvits, D. C. Gabuzda, C. J. Salter, D. R. Altschuler, P. Perillat, M. F. Aller, H. D. Aller, H. Hirabayashi, M. M. Davis. 2005-09-19. VSOP monitoring of the compact BL Lac object AO 0235+164. https://doi.org/10.1093/pasj%2F58.2.217

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