Seminars

Beauty meson to double charm decays at LHCb

by Dr. Fionn Bishop (LAPP Annecy)

Europe/London
R61 CR3 (RAL)

R61 CR3 (RAL)

Description

Multiple problems remain with the Standard Model (SM), including the abundance of matter over antimatter in the universe that motivates sources of charge-parity violation (CPV) beyond the SM (BSM). Double-charm B meson decays provide insight into both SM and BSM physics, especially BSM sources of CPV. Recent measurements of these decays with the LHCb detector will be discussed. Firstly, a search for sixteen decays of the Bc meson, which revealed the first evidence for the Bc->Ds+D0bar decay contrary to expectations, will be presented. If confirmed with future datasets, the measured branching fraction would require either a large departure from our understanding of the phenomenology of the Bc meson or a contribution from BSM physics. Secondly, measurements of CPV and branching fractions in the double-charm decays of the lighter B mesons will be presented, including the world-first measurement of several CP asymmetries. Flavour symmetries between these decays constrain subleading amplitudes permitting percent-level sensitivity to potential BSM contributions, and the implications of these measurements will also be discussed.