Lambda(c) -> Lambda l(+)nu(l) Form Factors and Decay Rates from Lattice QCD with Physical Quark Masses
AffiliationUniv Arizona, Dept Phys
MetadataShow full item record
PublisherAMER PHYSICAL SOC
CitationΛc → Λl + νl Form Factors and Decay Rates from Lattice QCD with Physical Quark Masses 2017, 118 (8) Physical Review Letters
JournalPhysical Review Letters
Rights© 2017 American Physical Society
Collection InformationThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at email@example.com.
AbstractThe first lattice QCD calculation of the form factors governing Lambda(c) -> Lambda l(+)nu(l) decays is reported. The calculation was performed with two different lattice spacings and includes one ensemble with a pion mass of 139(2) MeV. The resulting predictions for the Lambda(c) -> Lambda e(+)nu(e) and Lambda(c) -> Lambda mu(+)nu(mu) decay rates divided by vertical bar V-cs vertical bar(2) are 0.2007(71)(74) and 0.1945(69)(72) p(s-1), respectively, where the two uncertainties are statistical and systematic. Taking the Cabibbo-Kobayashi-Maskawa (CKM) matrix element vertical bar V-cs vertical bar from a global fit and the Lambda(c) lifetime from experiments, this translates to branching fractions of B(Lambda(c) -> Lambda e(e)(+nu)) = 0.0380(19)(LQCD)(11)(tau Lambda c) and B(Lambda(c) -> Lambda mu(+)nu(mu)) 0.0369(19)(LQCD)(11)(tau Lambda c). These results are consistent with, and two times more precise than, the measurements performed recently by the BESIII Collaboration. Using instead the measured branching fractions together with the lattice calculation to determine the CKM matrix element gives vertical bar V-cs vertical bar = 0.949(24)(LQCD)(14)(tau)Lambda c (49)(B).
VersionFinal published version
SponsorsNational Science Foundation [PHY-1520996, ACI-1053575]; RHIC Physics Fellow Program of the RIKEN BNL Research Center; National Energy Research Scientific Computing Center; U.S. Department of Energy [DE-AC02-05CH11231]