2005/11/30 by I. I. Bigi, Nikolai Uraltsev, N. Uraltsev +2 · 3 citations
Physics and Astronomy · #High-Energy Particle Collisions Research #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions #hep-ph
paper · pdf · doi:10.1140/epjc/s10052-007-0216-8
published as Eur.Phys.J.C50:539-556,2007 · 32 pages, LaTeX, 3 figures. Revised: A number of inconsistencies and typos corrected including the $1/m_c^2$ matrix elements. The effect on Γ_sl is estimated about 0.003, not changing the conclusions. A new reference [9] has been added
arxiv created 2006/06/17 · openalex publication_date 2007/03/05 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
We address the nonperturbative effects associated with soft charm quarks in inclusive B decays. Such corrections are allowed by the OPE, but have largely escaped attention so far. The related four-quark `double heavy' expectation values of the form <B|bc cb|B> are computed in the 1/mc expansion by integrating out the charm field to one and two loops. A significant enhancement of the two-loop coefficients has been noted. A method is suggested for evaluating the expectation values of the higher-order b-quark operators required to calculate charm expectation values, free from the overly large ambiguities of dimensional analyses. The soft-charm effects were found generally at the level of 0.5% in Γsl(b->c); however, as a result of cancellations the net impact should be smaller. We propose a direct way to search for such effects in the data. Finally, we discuss the relation of the soft charm corrections in inclusive decays with the `Intrinsic Charm' ansatz.