Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Unitarity Constraints on the B and B^* Form Factors from QCD Analyticity
  and Heavy Meson Spin Symmetry   A method of deriving bounds on the weak meson form factors, based on
perturbative QCD, analyticity and unitarity, is generalized in order to fully
exploit heavy quark spin symmetry in the ground state $(L=0)$ doublet of
pseudoscalar $(B)$ and vector $(B^*)$ mesons. All the relevant form factors of
these mesons are taken into account in the unitarity sum. They are treated as
independent functions along the timelike axis, being related by spin symmetry
only near the zero recoil point. Heavy quark vacuum polarisation up to three
loops in perturbative QCD and the experimental cross sections $\sigma(e^+e^-
\rightarrow \Upsilon)$ are used as input. We obtain bounds on the charge radius
of the elastic form factor of the $B$ meson, which considerably improve
previous results derived in the same framework.

37
The categories of this paper are: supr-con
15
The categories of this paper are: nucl-ex
7
The categories of this paper are: hep-th
6
The categories of this paper are: astro-ph
30
The categories of this paper are: q-alg
3
The categories of this paper are: physics
22
The categories of this paper are: chao-dyn
18
The categories of this paper are: econ
16
The categories of this paper are: stat
35
The categories of this paper are: mtrl-th
2
The categories of this paper are: math
17
The categories of this paper are: q-fin
8
The categories of this paper are: hep-ex
14
The categories of this paper are: math-ph
34
The categories of this paper are: chem-ph
29
The categories of this paper are: funct-an