Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Rare decays B\to M\nu\bar{\nu} in the TC2 model and the LHT model   In the framework of the topcolor-assisted technicolor ($TC2$) model and the
littlest Higgs model with $T$-parity ($LHT$ model), we consider the rare B
decays $B\to M\nu\bar{\nu}$ with $M=\pi,K,\rho,$ or $K^{\ast}$. We find that
the contributions of the $TC2$ model to the branching ratios of these decay
processes are larger than those for the $LHT$ model. The experimental upper
limits for some branching ratios can give severe constraints on the free
parameters of the $TC2$ model.

16
The categories of this paper are: stat
31
The categories of this paper are: ao-sci
37
The categories of this paper are: supr-con
28
The categories of this paper are: alg-geom
36
The categories of this paper are: cmp-lg
33
The categories of this paper are: plasm-ph
14
The categories of this paper are: math-ph
8
The categories of this paper are: hep-ex
29
The categories of this paper are: funct-an
6
The categories of this paper are: astro-ph
22
The categories of this paper are: chao-dyn
7
The categories of this paper are: hep-th
19
The categories of this paper are: eess
4
The categories of this paper are: cond-mat
25
The categories of this paper are: patt-sol
27
The categories of this paper are: comp-gas