Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Beauty hadron lifetime ratios and the problem of $\tau(\Lambda_b)$   We describe a theoretical approach to compute inclusive widths of heavy
hadrons, based on a systematic expansion in the inverse powers of the heavy
quark mass. The method reproduces quite well the experimental ratios of $B$
mesons lifetimes. As for $\tau(\Lambda_b)/\tau(B_d)$, we present a QCD sum rule
calculation of the $O(m_b^{-3})$ contribution to $\tau(\Lambda_b)$; we conclude
that such correction is not responsible of the small experimental value of
$\tau(\Lambda_b)/\tau(B_d)$.

9
The categories of this paper are: nlin
7
The categories of this paper are: hep-th
15
The categories of this paper are: nucl-ex
22
The categories of this paper are: chao-dyn
30
The categories of this paper are: q-alg
8
The categories of this paper are: hep-ex
21
The categories of this paper are: adap-org
19
The categories of this paper are: eess
23
The categories of this paper are: solv-int
29
The categories of this paper are: funct-an
20
The categories of this paper are: acc-phys
37
The categories of this paper are: supr-con
1
The categories of this paper are: cs
14
The categories of this paper are: math-ph
32
The categories of this paper are: atom-ph
27
The categories of this paper are: comp-gas