Speaker
Mr
Ciaran Hughes
(DAMTP, University of Cambridge)
Description
Recently Lewis and Woloshyn's exploratory study using lattice NRQCD to study the radiative decay $\Upsilon(2S) \to \eta_b(1S) \gamma$ found that next-to-leading order ($v^6$) contributions were large compared to the leading order ($v^4) result. We explain this suppression of the $v^4$ term using a simple potential model. We then present our lattice QCD results obtained with three lattice spacings and high statistics. We employ improved actions, twisted boundary conditions, 1-loop perturbative matching, and Bayesian fitting methods. We conclude that lattice NRQCD can be used to
accurately calculate this and other radiative bottomonium decay rates.
Primary authors
Mr
Ciaran Hughes
(DAMTP, University of Cambridge)
Dr
Georg M. Von Hippel
(Johannes Gutenberg-Universität Mainz)
Dr
Matthew Wingate
(DAMTP, University of Cambridge)
Dr
Rachel Dowdall
(DAMTP, University of Cambridge)
Prof.
Ronald R. Horgan
(DAMTP, University of Cambridge)
