VSOP Monitoring of the Compact BL Lac Object AO 0235 + 164 Sándor
نویسندگان
چکیده
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 TB > 5.8× 1013K (Frey et al. 2000). The sub-milliarcsec radio structure of this source has been studied with dualfrequency (1.6 and 5GHz), 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.
منابع مشابه
Dual - Frequency VSOP Observations of AO 0235 + 164
AO 0235+164 is a very compact, flat spectrum radio source identified as a BL Lac object at a redshift of z = 0.94. It is one of the most violently variable extragalactic objects at both optical and radio wavelengths. The radio structure of the source revealed by various ground-based VLBI observations is dominated by a nearly unresolved compact component at almost all available frequencies. Dual...
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