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We describe a recent lattice-QCD calculation of the leptonic decay con- stants of heavy-light pseudoscalar mesons containing charm and bottom quarks and of the masses of the up, down, strange, charm, and bottom quarks. Results for these quantities are of the highest precision to date. Calculations use 24 isospin-symmetric ensembles of gauge-field configura- tions with six different lattice spacings as small as approximately 0.03 fm and several values of the light quark masses down to physical values of the average up- and down-sea-quark masses. We use the highly-improved staggered quark (HISQ) formulation for valence and sea quarks, includ- ing the bottom quark. The analysis employs heavy-quark effective theory (HQET). A novel HQET method is used in the determination of the quark masses.
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This content will become publicly available on July 1, 2025
The quark-mass dependence of the potential energy between static colour sources in the QCD vacuum with light and strange quarks
The low-lying energy spectrum of the static-colour-source-anti-source system in a vacuum containing light and strange quarks is computed using lattice QCD for a range of different light quark masses. The resulting levels are described using a simple model Hamiltonian and the parameters in this model are extrapolated to the physical light-quark masses. In this framework, the QCD string tension is found to be sqrt(sigma) = 445(3)_stat (6)_sys MeV.
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- Award ID(s):
- 2209167
- PAR ID:
- 10517120
- Publisher / Repository:
- Science Direct
- Date Published:
- Journal Name:
- Physics Letters B
- Volume:
- 854
- Issue:
- C
- ISSN:
- 0370-2693
- Page Range / eLocation ID:
- 138754
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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