Effects from Hadronic Structure of Photon on $B\to\phi\gamma$ and $B_s\to(\rho^0,\omega)\gamma$ Decays

TL;DR

This paper investigates how the hadronic structure of photons influences rare B meson radiative decays using perturbative QCD, revealing significant enhancements in branching fractions and sensitivity to photon structure effects.

Contribution

It introduces the quark components and distribution amplitudes of the final state photon into the analysis of B decays, highlighting their impact on branching fractions and decay ratios.

Findings

Branching fraction of B→φγ increases by about 40 times.

Branching fractions of Bs→ρ^0γ and Bs→ωγ are around 10^{-10}.

The ratio of Bs→ρ^0γ to Bs→ωγ is highly sensitive to photon hadronic structure effects.

Abstract

Using the perturbative QCD approach, we studied the effects from hadronic structure of photon on the pure annihilation rediative decays $B\to\phi\gamma$ and $B_s\to(\rho^0,\omega)\gamma$. These decays have small branching fractions due to the power suppression by the $\Lambda/m_B$, which make them very sensitive to the next-leading power corrections. The quark components and the related two-particle distribution amplitudes of a final state photon are introduced. The branching fractions can be enhanced remarkably by the factorizable and nonfactorizable emission diagrams. The branching fraction of $B\to \phi\gamma$ even increases by about 40 times, and those of $B_s \to \rho^0\gamma$ and $B_s \to \omega\gamma$ are at the order of ${\cal O}(10^{-10})$. We also note that the ratio of branching fractions of $B_s \to \rho^0\gamma$ and $B_s \to \omega\gamma$ is very sensitive to the effects from hadronic structure of photon. All above results could be tested in future.