Renormalization of the tensor current in lattice QCD and the J / ψ tensor decay constant

Hatton, D., Davies, C.T.H. , Lepage, G.P. and Lytle, A.T. (2020) Renormalization of the tensor current in lattice QCD and the J / ψ tensor decay constant. Physical Review D, 102(9), 094509. (doi: 10.1103/PhysRevD.102.094509)

[img] Text
224182.pdf - Published Version
Available under License Creative Commons Attribution.



Lattice QCD calculations of form factors for rare Standard Model processes such as B → K ℓ + ℓ − use tensor currents that require renormalisation. These renormalisation factors, Z T , have typically been calculated within perturbation theory and the estimated uncertainties from missing higher order terms are significant. Here we study tensor current renormalisation using lattice implementations of momentum-subtraction schemes. Such schemes are potentially more accurate but have systematic errors from nonperturbative artefacts. To determine and remove these condensate contributions we calculate the ground-state charmonium tensor decay constant, f T J / ψ , which is also of interest in beyond the Standard Model studies. We obtain f T J / ψ ( MS , 2 G e V ) = 0.3927 ( 27 ) GeV, with ratio to the vector decay constant of 0.9569(52), significantly below 1. We also give Z T factors, converted to the M S scheme, corrected for condensate contamination. This contamination reaches 1.5% at a renormalisation scale of 2 GeV (in the preferred RI-SMOM scheme) and so must be removed for accurate results.

Item Type:Articles
Additional Information:The DIRAC component of CSD3 was funded by BEIS capital funding via STFC capital grants ST/P002307/1 and ST/R002452/1 and STFC operations grant ST/R00689X/1. DiRAC is part of the national e-infrastructure. We are grateful to the CSD3 support staff for assistance. Funding for this work came from the UK Science and Technology Facilities Council grants ST/L000466/1 and ST/P000746/1 and from the National Science Foundation.
Glasgow Author(s) Enlighten ID:Lytle, Dr Andrew and Hatton, Dr Daniel and Davies, Professor Christine
Authors: Hatton, D., Davies, C.T.H., Lepage, G.P., and Lytle, A.T.
College/School:College of Science and Engineering > School of Physics and Astronomy
Journal Name:Physical Review D
Publisher:American Physical Society
ISSN (Online):2470-0029
Published Online:13 November 2020
Copyright Holders:Copyright © 2020 American Physical Society
First Published:First published in Physical Review D 102(9): 094509
Publisher Policy:Reproduced under a Creative Commons License

University Staff: Request a correction | Enlighten Editors: Update this record

Project CodeAward NoProject NamePrincipal InvestigatorFunder's NameFunder RefLead Dept
173809Phenomenology from Lattice QCD and Collider PhysicsChristine DaviesScience and Technology Facilities Council (STFC)ST/P000746/1P&S - Physics & Astronomy
169715Phenomenology from Lattice QCD and collider physicsChristine DaviesScience and Technology Facilities Council (STFC)ST/L000466/1P&S - Physics & Astronomy