Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Non-mesonic Weak Decays of Light Hypernuclei in the Direct Quark and the
  One-Pion Exchange Mechanisms   Contributions of the direct quark mechanism are studied in the nonmesonic
weak decays of light hypernuclei. The $\Lambda N \to NN$ transition is
described by the one pion exchange mechanism and the direct quark mechanism,
induced by the four-quark vertices in the effective weak Hamiltonian. By
employing a realistic wave function of the $\Lambda$ inside the hypernuclei,
nonmesonic decay rates of $^4_{\Lambda}$H, $^4_{\Lambda}$He, and
$^5_{\Lambda}$He are calculated. The results show that the direct quark
mechanism is significantly large and gives a large $\Delta I =3/2$ contribution
in the J=0 channel. The relative phase between the one-pion exchange and the
direct-quark contributions is determined so that the effective weak Hamiltonian
for quarks give both of them consistently. We find that the sum of these two
contributions reproduce the current available experimental data fairly well.

13
The categories of this paper are: quant-ph
9
The categories of this paper are: nlin
31
The categories of this paper are: ao-sci
35
The categories of this paper are: mtrl-th
37
The categories of this paper are: supr-con
27
The categories of this paper are: comp-gas
30
The categories of this paper are: q-alg
11
The categories of this paper are: hep-lat
33
The categories of this paper are: plasm-ph
20
The categories of this paper are: acc-phys
26
The categories of this paper are: bayes-an
32
The categories of this paper are: atom-ph
24
The categories of this paper are: dg-ga
6
The categories of this paper are: astro-ph
34
The categories of this paper are: chem-ph
18
The categories of this paper are: econ