Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Spectator Effects in Inclusive Decays of Beauty Hadrons   We evaluate the matrix elements of the four-quark operators which contribute
to the lifetimes of $B$-mesons and the $\Lambda_b$-baryon. We find that the
spectator effects are not responsible for the discrepancy between the
theoretical prediction and experimental measurement of the ratio of lifetimes
$\tau(\Lambda_b)/\tau(B)$.

14
The categories of this paper are: math-ph
13
The categories of this paper are: quant-ph
22
The categories of this paper are: chao-dyn
26
The categories of this paper are: bayes-an
7
The categories of this paper are: hep-th
31
The categories of this paper are: ao-sci
29
The categories of this paper are: funct-an
23
The categories of this paper are: solv-int
18
The categories of this paper are: econ
30
The categories of this paper are: q-alg
17
The categories of this paper are: q-fin
21
The categories of this paper are: adap-org
37
The categories of this paper are: supr-con
6
The categories of this paper are: astro-ph
28
The categories of this paper are: alg-geom
3
The categories of this paper are: physics