Japanese VLBI Network Observations of a Gamma-Ray Narrow-Line Seyfert 1 Galaxy 1H 0323+342

Journal of astrophysics and astronomy

Naoki Isobe¹  Kenta Fujisawa³  Masaaki Hayashida⁴  Kiyoaki Wajima1² 

[1] The Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara 252-5210, Japan.$$;Shanghai Astronomical Observatory, Chinese Academy of Sciences, Shanghai 200030, China.$$;Research Institute for Time Studies, Yamaguchi University, Yamaguchi 753-8511, Japan.$$;Institute for Cosmic Ray Research, The University of Tokyo, Chiba 277-8582, Japan.$$

关键词: Galaxies: active;    galaxies: individual (1H 0323+342);    galaxies: Seyfert;    radio continuum: galaxies.;   

DOI  :  

学科分类：天文学(综合)

来源: Indian Academy of Sciences

【 摘 要 】

We made simultaneous single-dish and VLBI observations of a gamma-ray narrow-line Seyfert 1 (NLS1) galaxy 1H 0323+342. We found significant flux variation at 8 GHz on a time scale of one month. The total flux density varied by 5.5% in 32 days, corresponding to a variability brightness temperature of 7.0 × 1011 K. We also obtained brightness temperatures of greater than 5.2 × 1010 K from the VLBI images. These high brightness temperatures suggest that the source has nonthermal processes in the central engine. The source structure could be modelled by two elliptical Gaussian components on the parsec scales. The flux of the central component decreases in the same way as the total flux density, showing that the short-term variability is mainly associated with this component.

【 授权许可】

Unknown