Blob Ejection from Advection-dominated Accretion Flow: Observational Consequence
نویسندگان
چکیده
There is increasing evidence for the presence of an optically thin advection-dominated accretion flow (ADAF) in low luminosity active galactic nuclei and radio-loud quasars. The present paper is devoted to explore the fate of a blob ejected from an ADAF, and to discuss its observational consequences. It is inevitable for the ejected blob to drastically expand into its surroundings. Consequently, it is expected that a group of relativistic electrons should be accelerated, which may lead to nonthermal flares, since a strong shock will be formed by the interaction between the blob and its surroundings. Then the blob cools down efficiently, leading to the appearance of recombination lines about 10s after its ejection from an ADAF. We apply this model to NGC 4258 for some observational prediction, and to PKS 2149–306 for the explanation of observational evidence. Future simultaneous observations of recombination X-ray lines and continuum emission are highly desired to test the present model. Subject headings: accretion: accretion disk jet: emission galaxies: nuclei
منابع مشابه
Blob Ejection from Advection-dominated Accretion Flow: Observational Consequences
There is increasing evidence for the presence of an optically thin advection-dominated accretion flow (ADAF) in low luminosity active galactic nuclei and radio-loud quasars. The present paper is devoted to explore the fate of a blob ejected from an ADAF, and to discuss its observational consequences. It is inevitable for the ejected blob to drastically expand into its surroundings. Consequently...
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