Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Radiative magnetic reconnection near accreting black holes   A radiative mechanism is proposed for magnetic flares near luminous accreting
black holes. It is based on recent first-principle simulations of magnetic
reconnection, which show a hierarchical chain of fast-moving plasmoids. The
reconnection occurs in a compact region (comparable to the black hole radius),
and the chain experiences fast Compton cooling accompanied by electron-positron
pair creation. The distribution of plasmoid speeds is shaped by radiative
losses, and the self-regulated chain radiates its energy in hard X-rays. The
mechanism is illustrated by Monte-Carlo simulations of the transfer of seed
soft photons through the reconnection layer. The emerging radiation spectrum
has a cutoff near 100 keV similar to the hard-state spectra of X-ray binaries
and AGN. We discuss how the chain cooling differs from previous
phenomenological emission models, and suggest that it can explain the hard
X-ray activity of accreting black holes from first principles. Particles
accelerated at the X-points of the chain produce an additional high-energy
component, explaining "hybrid Comptonization" observed in Cyg X-1.

18
The categories of this paper are: econ
25
The categories of this paper are: patt-sol
4
The categories of this paper are: cond-mat
5
The categories of this paper are: gr-qc
2
The categories of this paper are: math
29
The categories of this paper are: funct-an
20
The categories of this paper are: acc-phys
31
The categories of this paper are: ao-sci
8
The categories of this paper are: hep-ex
36
The categories of this paper are: cmp-lg
0
The categories of this paper are: hep-ph
27
The categories of this paper are: comp-gas
28
The categories of this paper are: alg-geom
9
The categories of this paper are: nlin
13
The categories of this paper are: quant-ph
1
The categories of this paper are: cs