Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Gamma-Ray Spectroscopy of $^{16}_\Lambda$O and $^{15}_\Lambda$N
  Hypernuclei via the $^{16}$O$(K^-, \pi^-)$ reaction   he bound-state level structures of the $^{16}_{\Lambda}$O and
$^{15}_{\Lambda}$N hypernuclei were studied by $\gamma$-ray spectroscopy using
a germanium detector array (Hyperball) via the $^{16}$O ($K^-, \pi^- \gamma$)
reaction. A level scheme for $^{16}_{\Lambda}$O was determined from the
observation of three $\gamma$-ray transitions from the doublet of states
($2^-$,$1^-$) at $\sim 6.7$ MeV to the ground-state doublet ($1^-$,$0^-$). The
$^{15}_{\Lambda}$N hypernuclei were produced via proton emission from unbound
states in $^{16}_{\Lambda}$O . Three $\gamma$ -rays were observed and the
lifetime of the $1/2^+;1$ state in $^{15}_{\Lambda}$N was measured by the
Doppler shift attenuation method. By comparing the experimental results with
shell-model calculations, the spin-dependence of the $\Lambda N$ interaction is
discussed. In particular, the measured $^{16}_{\Lambda}$O ground-state doublet
spacing of 26.4 $\pm$ 1.6 $\pm$ 0.5 keV determines a small but nonzero strength
of the $\Lambda N$ tensor interaction.

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The categories of this paper are: mtrl-th
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The categories of this paper are: solv-int
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The categories of this paper are: q-fin
1
The categories of this paper are: cs
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The categories of this paper are: patt-sol
5
The categories of this paper are: gr-qc
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The categories of this paper are: supr-con
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The categories of this paper are: stat
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The categories of this paper are: econ
2
The categories of this paper are: math
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The categories of this paper are: dg-ga
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The categories of this paper are: nucl-th
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The categories of this paper are: atom-ph
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The categories of this paper are: alg-geom
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The categories of this paper are: chao-dyn
4
The categories of this paper are: cond-mat