Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Fourth generation effects in rare (B_s -> l^+ l^-) and (B_s -> l^+ l^-
  gamma) decays   The contribution of the fourth generation quarks to the rare (B_s -> l^+ l^-)
and (B_s -> l^+ l^- gamma) decays are studied. Constraints on the extended
Cabibbo-Kobayashi-Maskawa matrix elements |V_{tb} V_{ts}*| and |V_{t'b}
V_{t's}*| are obtained from the existing experimental result for the branching
ratio of the (B -> X_s gamma) decay. The branching ratios of the
above-mentioned decays, as well as the photon spectrum in the (B_s -> l^+ l^-
gamma) decay, are studied. It is found that the results are sensitive to the
existence of the fourth generation.

16
The categories of this paper are: stat
1
The categories of this paper are: cs
23
The categories of this paper are: solv-int
31
The categories of this paper are: ao-sci
20
The categories of this paper are: acc-phys
28
The categories of this paper are: alg-geom
36
The categories of this paper are: cmp-lg
13
The categories of this paper are: quant-ph
6
The categories of this paper are: astro-ph
22
The categories of this paper are: chao-dyn
18
The categories of this paper are: econ
30
The categories of this paper are: q-alg
10
The categories of this paper are: q-bio
14
The categories of this paper are: math-ph
11
The categories of this paper are: hep-lat
33
The categories of this paper are: plasm-ph