Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Detection of the Natural Alpha Decay of Tungsten   The natural alpha decay of 180W has been unambiguously detected for the first
time. The alpha peak is found in a (gamma,beta and neutron)-free background
spectrum. This has been achieved by the simultaneous measurement of phonon and
light signals with the CRESST cryogenic detectors. A half-life of T1/2 = (1.8
+- 0.2) x 10^18 y and an energy release of Q = (2516.4 +- 1.1 (stat.) +- 1.2
(sys.)) keV have been measured. New limits are also set on the half-lives of
the other naturally occurring tungsten isotopes.

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The categories of this paper are: cmp-lg
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The categories of this paper are: hep-lat
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The categories of this paper are: econ
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The categories of this paper are: eess
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The categories of this paper are: solv-int
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The categories of this paper are: dg-ga
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The categories of this paper are: acc-phys
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The categories of this paper are: math-ph
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The categories of this paper are: stat
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The categories of this paper are: funct-an
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The categories of this paper are: nlin
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The categories of this paper are: q-fin
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The categories of this paper are: chem-ph
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The categories of this paper are: ao-sci
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The categories of this paper are: patt-sol
5
The categories of this paper are: gr-qc