Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On the high-energy protons regular acceleration in the Fermi Bubbles   We propose the model of the global structure of the electromagnetic fields in
the Fermi bubbles (FBs), which makes possible the proton regular acceleration
up to ultra-high energies. The poloidal and the toroidal magnetic fields, as
well as the radial electric field, turn to have a structure similar to fields
that exist in jets ejected out from active galactic nuclei (AGN). A powerful
source of relativistic particles observed in the centre of the Galaxy and
associated with the rotating supermassive black hole (SMBH) Sgr A* can energize
the FB and keeps its active for a long time. The absence of accretion onto a BH
and thus the absence of a relativistic jet does not mean that there is no loss
of rotational energy of BH. In the case of FB, the energy lost by BH can keep
the FB activity. The regular FBs structure could be formed by inheritance from
a relativistic jet that presumably existed in the active past of the Galaxy $
10^7 $ years ago, or by processes near the Galaxy centre existing during the
entire life cycle of the Galaxy. The acceleration of protons in electromagnetic
fields of FB are found up to energies $ E_{max} \simeq 10^{17} $ eV, which
explains the observed radiation of FB in the gamma range, as well as the
emission of high-energy neutrinos.

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The categories of this paper are: math-ph
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The categories of this paper are: math
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The categories of this paper are: patt-sol
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The categories of this paper are: stat
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The categories of this paper are: ao-sci
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The categories of this paper are: q-bio
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The categories of this paper are: hep-ph
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The categories of this paper are: cs
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The categories of this paper are: nucl-ex
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The categories of this paper are: dg-ga
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The categories of this paper are: solv-int
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The categories of this paper are: adap-org
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The categories of this paper are: eess
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The categories of this paper are: chao-dyn
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The categories of this paper are: gr-qc
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The categories of this paper are: q-alg