decays revisited
arXiv:1509.07375 · doi:10.1007/JHEP02(2016)032
Abstract
We present a calculation of the width for decay. The amplitude of the process is computed within the NRQCD framework. The leading-order contribution is described by two terms associated with the two different integration domains in the electromagnetic loop describing two-photon annihilation of the heavy quark-antiquark pair. The corresponding operators are defined in the framework of NRQCD. The matrix element of one of these operators describes a configuration with an ultrasoft photon and can be associated with the higher Fock state of the heavy meson. In order to compute this contribution we use the heavy hadron chiral perturbation theory. We obtain that this contribution is numerically dominant. The obtained estimates for the decay widths of the and states are eV and eV, respectively.
revised version, couple mistakes in analytical expressions are fixed, numerical results for chi_{c2} are slightly modified
References in corpus (2)
Cited by in corpus (10)
- The states: experimental and theoretical status and perspectives
- decay and direct production in collisions
- and production at colliders
- First Observation of the Direct Production of the in Annihilation
- Production of the as the spin-2 partner of in collisions
- Towards a precision determination of the parameters from data
- Electroweak production of states in collisions: A brief review
- Testing properties at BELLE II
- Exclusive decays within the effective field theory framework
- Two-loop form factors for -wave quarkonium production and decay