B→Kl+l−decay form factors from three-flavor lattice QCD

Bailey, J. A. et al. (2016) B→Kl+l−decay form factors from three-flavor lattice QCD. Physical Review D, 93(2), 025026. (doi: 10.1103/PhysRevD.93.025026)

Abstract

We compute the form factors for the B→Kl+l− semileptonic decay process in lattice QCD using gauge-field ensembles with 2+1 flavors of sea quark, generated by the MILC Collaboration. The ensembles span lattice spacings from 0.12 to 0.045 fm and have multiple sea-quark masses to help control the chiral extrapolation. The asqtad improved staggered action is used for the light valence and sea quarks, and the clover action with the Fermilab interpretation is used for the heavy b quark. We present results for the form factors f+(q2), f0(q2), and fT(q2), where q2 is the momentum transfer, together with a comprehensive examination of systematic errors. Lattice QCD determines the form factors for a limited range of q2, and we use the model-independent z expansion to cover the whole kinematically allowed range. We present our final form-factor results as coefficients of the z expansion and the correlations between them, where the errors on the coefficients include statistical and all systematic uncertainties. We use this complete description of the form factors to test QCD predictions of the form factors at high and low q2.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Bouchard, Dr Chris and DeTar, Professor Carleton and Foley, Dr Justin
• Authors: Bailey, J. A., Bazavov, A., Bernard, C., Bouchard, C.M., DeTar, C., Du, D., El-Khadra, A.X., Foley, J., Freeland, E.D., Gámiz, E., Gottlieb, S., Heller, U.M., Jain, R.D., Komijani, J., Kronfeld, A.S., Laiho, J., Levkova, L., Liu, Y., Mackenzie, P.B., Meurice, Y., Neil, E.T., Qiu, S.-W., Simone, J.N., Sugar, R., Toussaint, D., Van de Water, R.S., and Zhou, R.
• College/School: College of Science and Engineering > School of Physics and Astronomy
• Journal Name: Physical Review D
• Publisher: American Physical Society
• ISSN: 1550-7998
• ISSN (Online): 1550-2368
• Copyright Holders: Copyright © 2016 American Physical Society
• First Published: First published in Physical Review D 93(2): 025026
• Publisher Policy: Reproduced in accordance with the publisher copyright policy