Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Search for Neutrinoless Double-Beta Decay   After the pioneering work of the Heidelberg-Moscow (HDM) and International
Germanium Experiment (IGEX) groups, the second round of neutrinoless
double-$\beta$ decay searches currently underway has or will improve the
life-time limits of double-$\beta$ decay candidates by a factor of two to
three, reaching in the near future the $T_{1/2} = 3 \times 10^{25}$ yr level.
This talk will focus on the large-scale experiments GERDA, EXO-200, and
KamLAND-Zen, which have reported already lower half-life time limits in excess
of $10^{25}$ yr. Special emphasis is given to KamLAND-Zen, which is expected to
approach the inverted hierarchy regime before future 1-ton experiments probe
completely this life-time or effective neutrino-mass regime, which starts at
$\approx 2 \times 10^{26}$ yr or $\approx 50$ meV.

8
The categories of this paper are: hep-ex
6
The categories of this paper are: astro-ph
34
The categories of this paper are: chem-ph
12
The categories of this paper are: nucl-th
1
The categories of this paper are: cs
10
The categories of this paper are: q-bio
30
The categories of this paper are: q-alg
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The categories of this paper are: gr-qc
22
The categories of this paper are: chao-dyn
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
29
The categories of this paper are: funct-an
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The categories of this paper are: hep-th
20
The categories of this paper are: acc-phys
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The categories of this paper are: cmp-lg