Publication detailsMannel, T., Pecjak, B.D. & Pivovarov, A.A. (2011). Sum rule estimate of the subleading non-perturbative contributions to B s –B¯sB¯s mixing. The European Physical Journal C 71(4): 1607.
- Publication type: Journal Article
- ISSN/ISBN: 1434-6044 (print), 1434-6052 (electronic)
- DOI: 10.1140/epjc/s10052-011-1607-4
- Further publication details on publisher web site
Author(s) from Durham
We use QCD sum rules to compute the matrix elements of the ΔB=2 operators appearing in the heavy-quark expansion of the width difference of the B s mass eigenstates. The main focus of our analysis is on the subleading operators R 2 and R 3, which appear at next-to-leading order in the 1/m b expansion. The matrix elements of these operators are already essential for precise phenomenology, but their calculation in lattice QCD is lacking and the values given here provide a first estimate of their values. We conclude that the violation of the factorization approximation for these matrix elements due to non-perturbative vacuum condensates is as low as 1–2%.