Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Nuclear Physics of Double Beta Decay   Study of the neutrinoless $\beta\beta$ decay allows us to put a stringent
limit on the effective neutrino Majorana mass, a quantity of fundamental
importance. To test our ability to evaluate the nuclear matrix elements that
govern the decay rate, it is desirable to be able to describe the allowed
two-neutrino decay. It is argued that only low-lying virtual intermediate
states are important for that process, and thus it appears that the large-scale
shell model evaluation, free from the various difficulties of QRPA, is the
preferred method. In the $0\nu$ decay, it is shown that there is a substantial
cancellation between the paired and broken pair pieces of the nuclear wave
function. Thus, despite the popular claim to the contrary, one expects that the
$0\nu$ rate is also sensitive to the details of nuclear structure. This is
reflected in the spread of the theoretical values, leading to the uncertainty
of about factor 2-3 in the deduced $<m_{\nu}>$ limit. Finally, brief comment
about the $0\nu$ decay with the exchange of a very heavy neutrino are made.

22
The categories of this paper are: chao-dyn
10
The categories of this paper are: q-bio
28
The categories of this paper are: alg-geom
26
The categories of this paper are: bayes-an
21
The categories of this paper are: adap-org
30
The categories of this paper are: q-alg
6
The categories of this paper are: astro-ph
25
The categories of this paper are: patt-sol
33
The categories of this paper are: plasm-ph
8
The categories of this paper are: hep-ex
34
The categories of this paper are: chem-ph
17
The categories of this paper are: q-fin
9
The categories of this paper are: nlin
16
The categories of this paper are: stat
36
The categories of this paper are: cmp-lg
14
The categories of this paper are: math-ph