QCD@Work - International Workshop on QCD - Theory and Experiment

Inclusive rare Λb decays to photon

18 Jun 2024, 15:50

20m

Talk Session 3

Speaker

Francesco Loparco (Istituto Nazionale di Fisica Nucleare)

Description

I present an analysis of the inclusive $H_b\to X_s\gamma$ decay with $H_b$ a beauty baryon, in particular ${\mathrm{\Lambda }}_b$, employing an expansion in the heavy quark mass at $\mathcal{O}(m_b^{-3})$ at leading order in ${\alpha }_s$.
For a polarized baryon I show the results for the distribution ${\displaystyle \frac{d^2\mathrm{\Gamma }}{dyd\cos {\theta }_P}}$, with $y=2E_{\gamma }/m_b$, $E_{\gamma }$ the photon energy and ${\theta }_P$ the angle between the baryon spin vector and the photon momentum in the $H_b$ rest-frame.
I discuss the correlation between the baryon spin and the photon polarization, and show how effects of physics beyond the Standard Model can modify the photon polarization asymmetry.
I also present a method to treat the singular terms in the photon energy distribution.

Presentation materials

Francesco_Loparco_Trani_QCDatWork.pdf