Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Higher-order multipole amplitude measurement in
  $\psi(2S)\to\gamma\chi_{c2}$   Using $106\times10^6$ $\psi(2S)$ events collected with the BESIII detector at
the BEPCII storage ring, the higher-order multipole amplitudes in the radiative
transition $\psi(2S)\to\gamma\chi_{c2}\to\gamma\pi\pi/\gamma KK$ are measured.
A fit to the $\chi_{c2}$ production and decay angular distributions yields
$M2=0.046\pm0.010\pm0.013$ and $E3=0.015\pm0.008\pm0.018$, where the first
errors are statistical and the second systematic. Here $M2$ denotes the
normalized magnetic quadrupole amplitude and $E3$ the normalized electric
octupole amplitude. This measurement shows evidence for the existence of the
$M2$ signal with $4.4\sigma$ statistical significance and is consistent with
the charm quark having no anomalous magnetic moment.

31
The categories of this paper are: ao-sci
34
The categories of this paper are: chem-ph
29
The categories of this paper are: funct-an
9
The categories of this paper are: nlin
3
The categories of this paper are: physics
19
The categories of this paper are: eess
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The categories of this paper are: comp-gas
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The categories of this paper are: alg-geom
11
The categories of this paper are: hep-lat
16
The categories of this paper are: stat
26
The categories of this paper are: bayes-an
13
The categories of this paper are: quant-ph
24
The categories of this paper are: dg-ga
32
The categories of this paper are: atom-ph
12
The categories of this paper are: nucl-th
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The categories of this paper are: q-fin