Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Recoil alignment in muon capture on nitrogen-14   We report a measurement of the longitudinal alignment $A_L$ of the recoil
nucleus in the $\mu^- + ^{14}$N$(1^+, 0)$ $\to$ $\nu_{\mu} + ^{14}$C$(2^+,
7012)$ transition. The experiment was performed on the M9B beamline at the
TRIUMF cyclotron via the measurement of the Doppler lineshape of the subsequent
$^{14}$C$(2^+, 7012)$ $\to$ $^{14}$C$(0^+, 0)$ gamma-rays. We compare our
result $A_L = 0.60 \pm 0.11$ to various model calculations, and discuss the
sensitivity to the induced pseudoscalar coupling, second-forbidden effects and
$2 \hbar \omega$ wavefunction admixtures.

14
The categories of this paper are: math-ph
19
The categories of this paper are: eess
27
The categories of this paper are: comp-gas
32
The categories of this paper are: atom-ph
6
The categories of this paper are: astro-ph
10
The categories of this paper are: q-bio
7
The categories of this paper are: hep-th
2
The categories of this paper are: math
20
The categories of this paper are: acc-phys
18
The categories of this paper are: econ
21
The categories of this paper are: adap-org
17
The categories of this paper are: q-fin
33
The categories of this paper are: plasm-ph
31
The categories of this paper are: ao-sci
36
The categories of this paper are: cmp-lg
1
The categories of this paper are: cs