Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Consistent large-scale shell-model analysis of the two-neutrino
  $\beta\beta$ and single $\beta$ branchings in $^{48}\rm Ca$ and $^{96}\rm Zr$   Two-neutrino double-beta-decay matrix elements $M_{2\nu}$ and single
beta-decay branching ratios were calculated for $^{48}$Ca and $^{96}$Zr in the
interacting nuclear shell model using large single-particle valence spaces with
well-tested two-body Hamiltonians. For $^{48}$Ca the matrix element
$M_{2\nu}=0.0511$ is obtained, which is 5.5\% smaller than the previously
reported value of 0.0539. For $^{96}$Zr this work reports the first large-scale
shell-model calculation of the nuclear matrix element, yielding a value
$M_{2\nu}=0.0747$ with extreme single-state dominance. If the scenario where
the first $1^+$ state in $^{96}$Nb is at 694.6 keV turns out to be correct, the
matrix element is increased to 0.0854. These matrix elements, combined with the
available $\beta\beta$-decay half-life data, yield effective values of the weak
axial coupling which in turn are used to produce in a consistent way the
$\beta$-decay branching ratios of $(7.5\pm2.8)$ % for $^{48}$Ca and
$(18.4\pm0.09)$ % for $^{96}$Zr. These are larger than obtained in previous
studies, implying that the detection of the $\beta$-decay branches could be
possible in dedicated experiments sometime in the (near) future.

31
The categories of this paper are: ao-sci
26
The categories of this paper are: bayes-an
11
The categories of this paper are: hep-lat
33
The categories of this paper are: plasm-ph
4
The categories of this paper are: cond-mat
2
The categories of this paper are: math
32
The categories of this paper are: atom-ph
27
The categories of this paper are: comp-gas
9
The categories of this paper are: nlin
35
The categories of this paper are: mtrl-th
30
The categories of this paper are: q-alg
36
The categories of this paper are: cmp-lg
18
The categories of this paper are: econ
3
The categories of this paper are: physics
21
The categories of this paper are: adap-org
28
The categories of this paper are: alg-geom