Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Double Penguins and the Contribution of Vector Meson--like States to the
  Decays $B \to K^* \gamma, \, B \to \rho \gamma$   Using perturbative QCD, the contribution at the leading twist, leading
$\alpha_s$ level, of charm and up quark loops to the decays $B \rightarrow K^*
\gamma$ and $B \rightarrow \rho \gamma$ is presented. In the case of $B
\rightarrow \rho \gamma$, the relative importance of these contributions depend
upon the unknown CKM matrix elements $V_{bu}$ and $V_{td}$.
  Assuming that the ratio $r = V_{bc}V^*_{cd}/V_{bt}V^*_{td}$ is bounded
between $-2.25 \le r \le -.5$ as is suggested by the Particle Data Group, the
error in extracting $ |V_{td}/V_{ts}| $ by these decays is estimated.

37
The categories of this paper are: supr-con
17
The categories of this paper are: q-fin
28
The categories of this paper are: alg-geom
11
The categories of this paper are: hep-lat
25
The categories of this paper are: patt-sol
31
The categories of this paper are: ao-sci
26
The categories of this paper are: bayes-an
6
The categories of this paper are: astro-ph
32
The categories of this paper are: atom-ph
15
The categories of this paper are: nucl-ex
22
The categories of this paper are: chao-dyn
27
The categories of this paper are: comp-gas
35
The categories of this paper are: mtrl-th
5
The categories of this paper are: gr-qc
20
The categories of this paper are: acc-phys
3
The categories of this paper are: physics