Marco Fatuzzo, Fulvio Melia
The presence of relativistic particles at the center of our galaxy is
evidenced by the diffuse TeV emission detected from the inner $\sim$$2^\circ$
of the Galaxy. Although it is not yet entirely clear whether the origin of the
TeV photons is due to hadronic or leptonic interactions, the tight correlation
of the intensity distribution with the distribution of molecular gas along the
Galactic ridge strongly points to a pionic-decay process involving relativistic
protons. In earlier work, we concluded that point-source candidates, such as
the supermassive black hole Sagittarius A* (identified with the HESS source
J1745-290), or the pulsar wind nebulae dispersed along the Galactic plane,
could not account for the observed diffuse TeV emission from this region.
Motivated by this result, we consider here the feasibility that the cosmic rays
populating the Galactic Center (GC) region are accelerated in situ by magnetic
turbulence. Our results indicate that even in a highly conductive environment,
this mechanism is efficient enough to energize protons within the intercloud
medium to the $\ga $ TeV energies required to produce the HESS emission.
View original:
http://arxiv.org/abs/1202.4680
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