riassunto2

HE1 - Experimental tests of fundamental physics with high energy gamma rays

Speaker

de Gouveia Dal Pino, Elisabete

Coauthors

Talk Title

On the origin of the gamma ray emission and cosmic rays in the surrounds of the Black Hole Sources of the Fundamental Plane

Abstract

The current detectors of gamma-ray emission have too poor resolution to determine whether this emission is produced in the jet or in the core of AGNs (particularly the non-blazars, low luminous AGNs - LLAGNs) and black-hole binaries (BHBs). We have computed the power released by events of fast magnetic reconnection between the magnetic lines arising from the accretion disk and those of the black hole (BH) magnetosphere triggered by enhanced accretion, and found that this power is more than sufficient to reproduce the observed (core) radio and the gamma-ray luminosities of LLAGNs and microquasars, but not those of the luminous blazars. Moreover, this calculated power has a dependence with the BH mass of the sources that matches very well with the observed correlation between the luminosity and mass of these sources sustained for over 10 orders of magnitude in mass (using a sample with more than 100 sources, including those of the so called fundamental plane of black hole activity of Merloni et al. 2003). This match suggests a core origin for the gamma-ray emission in these sources. Besides, based on 3D MHD simulations with test particles, we demonstrated that these suffer a first-order Fermi acceleration within the reconnection site (as first proposed by de Gouveia Dal Pino aLazand rian 2005) at very efficient rates in the surrounds of the BHs. Then, employing this acceleration model driven by turbulent fast magnetic reconnection events in the core region, we computed the spectral energy distribution (SED) of several radio galaxies and microquasars and found that these SEDs also match quite well with the observations, therefore strengthening the conclusions above in favor of a core emission for the gamma-rays of these sources. We have also found that the process is nearly independent of the details of the accretion physics as it occurs in the coronal region around the BH and accretion disk (tested for different accretion models and rates).

Talk view

HE1-2181DE1218TE.pdf

 

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