Speaker
Dr
Mateusz Koren
(NIC, DESY Zeuthen)
Description
The extraction of bare ground-state matrix elements for $B_s \to K\ell\nu$ decay at 2% precision poses a significant numerical challenge. Especially the B-sector, treated in HQET, is problematic due to large contamination by excited states combined with the signal-to-noise problem. The numerical setup that we use provides access to all time separations for both the two-point and three-point correlation functions of interest, for several different smearings. Using this data, we show how the extraction is achieved using two different techniques - the combined fits to two- and three-point correlation functions, as well as the ratio method (where we compare different possible ratio definitions, including summed ratios).
Primary author
Dr
Mateusz Koren
(NIC, DESY Zeuthen)
Co-authors
Dr
Debasish Banerjee
(NIC, DESY)
Dr
Felix Bahr
(NIC, DESY Zeuthen)
Prof.
Hubert Simma
(NIC, DESY Zeuthen)
Prof.
Rainer Sommer
(NIC @ DESY)
