Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: An overview of the JEM-EUSO program and results   The field of UHECRs (Ultra-High energy cosmic Rays) and the understanding of
particle acceleration in the cosmos, as a key ingredient to the behaviour of
the most powerful sources in the universe, is of outmost importance for
astroparticle physics as well as for fundamental physics and will improve our
general understanding of the universe. The current main goals are to identify
sources of UHECRs and their composition. For this, increased statistics is
required. A space-based detector for UHECR research has the advantage of a very
large exposure and a uniform coverage of the celestial sphere. The aim of the
JEM-EUSO program is to bring the study of UHECRs to space. The principle of
observation is based on the detection of UV light emitted by isotropic
fluorescence of atmospheric nitrogen excited by the Extensive Air Showers (EAS)
in the Earth's atmosphere and forward-beamed Cherenkov radiation reflected from
the Earth's surface or dense cloud tops. In addition to the prime objective of
UHECR studies, JEMEUSO will do several secondary studies due to the
instruments' unique capacity of detecting very weak UV-signals with extreme
time-resolution around 1 microsecond: meteors, Transient Luminous Events (TLE),
bioluminescence, maps of human generated UV-light, searches for Strange Quark
Matter (SQM) and high-energy neutrinos, and more. The JEM-EUSO program includes
several missions from ground (EUSO-TA), from stratospheric balloons
(EUSO-Balloon, EUSO-SPB1, EUSO-SPB2), and from space (TUS, Mini-EUSO) employing
fluorescence detectors to demonstrate the UHECR observation from space and
prepare the large size missions K-EUSO and POEMMA. A review of the current
status of the program, the key results obtained so far by the different
projects, and the perspectives for the near future are presented.

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The categories of this paper are: quant-ph
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The categories of this paper are: solv-int
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The categories of this paper are: alg-geom
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The categories of this paper are: patt-sol
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The categories of this paper are: cond-mat
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The categories of this paper are: eess
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The categories of this paper are: econ
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The categories of this paper are: bayes-an
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The categories of this paper are: hep-th
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The categories of this paper are: chem-ph
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The categories of this paper are: q-alg
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The categories of this paper are: cmp-lg
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The categories of this paper are: math-ph
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The categories of this paper are: gr-qc
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The categories of this paper are: q-bio
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The categories of this paper are: hep-ph