Abstract
We summarize our recently improved results for the pseudoscalar [S. Narison, Phys.Lett. B718 (2013) 132; S. Narison, Nucl. Phys. Proc. Suppl. 234 (2013) 187; S. Narison, Phys.Lett. B721 (2013) 269], vector and Bc [S. Narison, Int. J. Mod. Phys. A30 (2015) 20, 1550116] meson decay constants from QCD spectral sum rules where N2LO⊕ estimate of the N3LO PT⊕d≤6 condensates have been included in the SVZ expansion. The “optimal results” based on stability criteria with respect to the variations of the Laplace/Moments sum rule variables, QCD continuum threshold and subtraction constant μ are compared with recent sum rules and lattice calculations. To understand the “apparent tension” between some recent results, we present in Section 8 a novel extraction of forfB⁎/fBfrom heavy quark effective theory (HQET) sum rules by including the normalization factor (Mb/MB)2 relating the pseudoscalar to the universal HQET correlators for finite b-quark and B-meson masses. We obtain fB⁎/fB=1.025(16) in good agreement with 1.016(16) from spectral sum rules (SR) in full QCD [3]. We complete the paper by including new improved estimates of the scalar, axial andBc⁎meson decay constants (Sections 11–13). For further phenomenological uses, we attempt to extract a Global Average of the sum rules and lattice determinations which are summarized in Tables 2–6. We do not found any deviation of these SM results from the present data.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.