The dynamic age of Centaurus A

• 出版年: New Journal of Physics
• 第一著者: Jean A Eilek
• フォーマット: 論文
• 言語: 英語
• 出版事項: IOP Publishing 2014-01-01
• 主題: radio galaxies; particle acceleration; MHD
• オンライン･アクセス: https://doi.org/10.1088/1367-2630/16/4/045001

In this paper I present dynamic models of the radio source Centaurus A, and critique possible models of in situ particle reacceleration (ISR) within the radio lobes. The radio and γ -ray data require neither homogeneous plasma nor quasi-equipartition between the plasma and magnetic field; inhomogeneous models containing both high-field and low-field regions are equally likely. Cen A cannot be as young as the radiative lifetimes of its relativistic electrons, which range from a few to several tens of Myr. Two classes of dynamic models—flow driven and magnetically driven—are consistent with current observations; each requires Cen A to be on the order of a Gyr old. Thus, ongoing ISR must be occuring within the radio source. Alfven-wave ISR is probably occuring throughout the source, and may be responsible for maintaining the γ -ray-loud electrons. This is likely to be supplemented by shock or reconnection ISR, which maintains the radio-loud electrons in high-field regions.