Physics – High Energy Physics – High Energy Physics - Phenomenology
Scientific paper
1997-05-07
Phys.Rev. D56 (1997) 6895-6911
Physics
High Energy Physics
High Energy Physics - Phenomenology
45 pages, RevTeX. Version to appear in Phys. Rev. D. Improved statistical analysis reveals that our fit is competitive with ad
Scientific paper
10.1103/PhysRevD.56.6895
We present precision corrections to dispersion relation bounds on form factors in bottom hadron semileptonic decays and analyze their effects on parameterizations derived from these bounds. We incorporate QCD two-loop and nonperturbative corrections to the two-point correlator, consider form factors whose contribution to decay rates is suppressed by lepton mass, and implement more realistic estimates of truncation errors associated with the parameterizations. We include higher resonances in the hadronic sum that, together with heavy quark symmetry relations near zero recoil, further tighten the sum rule bounds. Utilizing all these improvements, we show that each of the six form factors in B --> D l nu and B --> D^* l nu can be described with 3% or smaller precision using only the overall normalization and one unknown parameter. A similar one-coefficient parameterization of one of the Lambda_b --> Lambda_c l nu form factors, together with heavy quark symmetry relations valid to order 1/m^2, describes the differential baryon decay rate in terms of one unknown parameter and the phenomenologically interesting quantity (\bar Lambda)_Lambda \approx M_{Lambda_b} - m_b. We discuss the validity of slope-curvature relations derived by Caprini and Neubert, and present weaker, corrected relations. Finally, we present sample fits of current experimental B --> D^*l nu and B --> D l nu data to the improved one-parameter expansion.
Boyd Glenn C.
Grinstein Benjamin
Lebed Richard F.
No associations
LandOfFree
Precision Corrections to Dispersive Bounds on Form Factors does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Precision Corrections to Dispersive Bounds on Form Factors, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Precision Corrections to Dispersive Bounds on Form Factors will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-399745