New prediction of extragalactic GeV gamma-ray emission from radio lobes of young AGN jets

作者：Kino M^*; Ito H; Kawakatu N; Nagai H

来源：Monthly Notices of the Royal Astronomical Society, 2009, 395(1): L43-L47.

DOI：10.1111/j.1745-3933.2009.00638.x

• galaxies: active
• galaxies: jets
• gamma-rays: theory

We present a new prediction of GeV gamma-ray emission from radio lobes of young active galactic nuclei jets. In the previous work of Kino, Kawakatu & Ito, MeV gamma-ray bremsstrahlung emission was predicted from young cocoons/radio lobes in the regime of no coolings. In this study, we include cooling effects of bremsstrahlung emission and adiabatic loss. With the initial conditions determined by observed young radio lobes, we solve a set of equations describing the expanding lobe evolution. Then, we find that the lobes initially have electron temperature of similar to GeV, and they cool down to similar to MeV by the adiabatic loss. Correspondingly, the lobes initially yield bright bremsstrahlung luminosity in similar to GeV range and they fade out. We estimate these gamma-ray emissions and show that nearby young radio lobes could be detected with Fermi Gamma-ray Space Telescope.

• 出版日期2009-5-1
• 单位中国科学院国家天文台