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Title: B- and D-meson semileptonic decays with highly improved staggered quarks
We present results for B(s)- and D(s)-meson semileptonic decays from ongoing calculations by the Fermilab Lattice and MILC Collaborations. Our calculation employs the highly improved stag- gered quark (HISQ) action for both sea and valence quarks and includes several ensembles with physical-mass up, down, strange, and charm quarks and lattice spacings ranging from a ≈ 0.15 fm down to 0.06 fm. At most lattice spacings, an ensemble with physical-mass light quarks is included. The use of the highly improved action, combined with the MILC Collaboration’s gauge ensembles with lattice spacings down to a ≈ 0.042 fm, allows heavy valence quarks to be treated with the same discretization as the light and strange quarks. This unified treatment of the valence quarks allows (in some cases) for absolutely normalized currents, bypassing the need for perturbative matching, which has been a leading source of uncertainty in previous calculations of B-meson decay form factors by our collaboration. All preliminary form-factor results are blinded.
Authors:
; ; ; ; ; ; ; ; ;
Award ID(s):
2013064
Publication Date:
NSF-PAR ID:
10340522
Journal Name:
The 38th International Symposium on Lattice Field Theory (LATTICE2021)
Volume:
396
Page Range or eLocation-ID:
109
Sponsoring Org:
National Science Foundation
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