Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The beta decay of 38Ca: Sensitive test of isospin symmetry-breaking
  corrections from mirror superallowed 0+-to-0+ transitions   We report the first branching-ratio measurement of the superallowed 0+-to-0+
beta transition from 38Ca. The result, 0.7728(16), leads to an ft value of
3062.3(68)s with a relative precision of +/-0.2%. This makes possible a
high-precision comparison of the ft values for the mirror superallowed
transitions, 38Ca-to-38mK and 38mK-to-38Ar, which sensitively tests the isospin
symmetry-breaking corrections required to extract Vud, the up-down quark-mixing
element of the Cabibbo-Kobayashi-Maskawa (CKM) matrix, from superallowed beta
decay. The result supports the corrections currently used, and points the way
to even tighter constraints on CKM unitarity.

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The categories of this paper are: econ
11
The categories of this paper are: hep-lat
6
The categories of this paper are: astro-ph
24
The categories of this paper are: dg-ga
22
The categories of this paper are: chao-dyn
37
The categories of this paper are: supr-con
30
The categories of this paper are: q-alg
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The categories of this paper are: patt-sol
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The categories of this paper are: mtrl-th
36
The categories of this paper are: cmp-lg
29
The categories of this paper are: funct-an
26
The categories of this paper are: bayes-an
1
The categories of this paper are: cs
8
The categories of this paper are: hep-ex
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The categories of this paper are: eess
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The categories of this paper are: quant-ph