Accurate decay-constant ratios fB*/fB and fBs*/fBs from Borel QCD sum rules

Autor(en)
Wolfgang Lucha, Dmitri Melikhov, Silvano Simula
Abstrakt

We present our analysis of the decay constants of the beauty vector mesons B∗ and B

s∗ within the framework of dispersive sum rules for the two-point correlator of vector currents in QCD. While the decay constants of the vector mesons f

B∗ and f

Bs∗ - similar to the decay constants of the pseudoscalar mesons f

B and f

Bs - individually have large uncertainties induced by theory parameters not known with a satisfactory precision, these uncertainties almost entirely cancel out in the ratios of vector over pseudoscalar decay constants. These ratios, thus, may be predicted with very high accuracy due to the good control over the systematic uncertainties of the decay constants gained upon application of our hadron-parameter extraction algorithm. Our final results read f

B∗/f

B = 0.944 ± 0.011

OPE ± 0.018

syst and f

Bs∗/f

Bs = 0.947 ± 0.023

OPE ± 0.020

syst. Thus, both f

B∗/f

B and f

Bs∗/f

Bs are less than unity at 2.5σ and 2σ level, respectively.

Organisation(en)
Teilchenphysik
Externe Organisation(en)
Österreichische Akademie der Wissenschaften (ÖAW), Lomonosov Moscow State University (MSU), Istituto Nazionale di Fisica Nucleare (INFN), Roma
Journal
Physical Review D
Band
91
Anzahl der Seiten
10
ISSN
1550-7998
DOI
https://doi.org/10.1103/PhysRevD.91.116009
Publikationsdatum
06-2015
Peer-reviewed
Ja
ÖFOS 2012
103034 Teilchenphysik
Schlagwörter
ASJC Scopus Sachgebiete
Nuclear and High Energy Physics, Physics and Astronomy (miscellaneous)
Link zum Portal
https://ucrisportal.univie.ac.at/de/publications/accurate-decayconstant-ratios-fbfb-and-fbsfbs-from-borel-qcd-sum-rules(c19fd942-3868-4cdc-94ef-59d08854ee7e).html