Reanalysis of the Four-Quark Operators Relevant to Λ_b Lifetime from QCD Sum Rule

Abstract

Λ_b matrix element of four-quark operator relevant to its lifetime is reanalyzed by QCD sum rule. The new ingredients introduced are that (1) more vacuum condensates are considered; (2) different quark-hadron duality is adopted; and (3) the possible deviation from the vacuum saturation assumption for the four quark condensates is considered. With κ_1=4 the related hadronic parameter r is calculated to be 3.6 \pm 0.9, and the lifetime ratio τ(Λ_b)/τ(B^0) = 0.83 \pm 0.04, which is consistent with the experimental data.

12 pages, revtex, one figure, more discussions and references added

References in corpus (4)

• Duality-Violating 1/m_Q Effects in Heavy Quark Decay
• Enhancement of preasymptotic effects in inclusive beauty decays
• Non-Spectator Contributions to Inclusive Charmless $B$ Decays
• Measuring V_ub in Inclusive B Decays to Charm

Cited by in corpus (5)

• Lifetime Ratios of Beauty Hadrons at the Next-to-Leading Order in QCD
• Next-to-Leading Order QCD Corrections to Spectator Effects in Lifetimes of Beauty Hadrons
• Quark-hadron duality at work: lifetimes of bottom baryons
• A note on spectator effects and quark-hadron duality in inclusive beauty decays
• Matrix elements of $\Delta B=0$ operators in heavy hadron chiral perturbation theory