Weak radiative decay using light-cone sum rules
arXiv:2212.01111 · doi:10.1140/epjc/s10052-023-11362-9
Abstract
We calculate the decay width of the using light-cone sum rules. For the initial quark radiation an effective Hamiltonian is constructed, where the internal quark line shrinks to a point. The final quark radiation is studied within the full theory. The leading twist light-cone distribution amplitudes of the serve as the non-perturbative input for the sum rules calculation, and the perturbative kernel is calculated at leading order. The branching fraction we obtain is , which is below the recent upper limit given by the Belle collaboration.
13 pages, 3 figures and 2 tables