Parameters of Heavy Quark Effective Theory from Nf=2 lattice QCD

Benoit Blossier; Michele Della Morte; Patrick Fritzsch; Nicolas Garron; Jochen Heitger; Hubert Simma; Rainer Sommer; Nazario Tantalo

doi:10.1007/jhep09(2012)132

arXiv · 1203.6516

Parameters of Heavy Quark Effective Theory from Nf=2 lattice QCD

Benoit Blossier·Michele Della Morte·Patrick Fritzsch·Nicolas Garron·Jochen Heitger·Hubert Simma·Rainer Sommer·Nazario Tantalo

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Abstract

We report on a non-perturbative determination of the parameters of the lattice Heavy Quark Effective Theory (HQET) Lagrangian and of the time component of the heavy-light axial-vector current with Nf=2 flavors of massless dynamical quarks. The effective theory is considered at the 1/mh order, and the heavy mass mh covers a range from slightly above the charm to beyond the beauty region. These HQET parameters are needed to compute, for example, the b-quark mass, the heavy-light spectrum and decay constants in the static approximation and to order 1/mh in HQET. The determination of the parameters is done non-perturbatively. The computation reported in this paper uses the plaquette gauge action and two different static actions for the heavy quark described by HQET. For the light-quark action we choose non-perturbatively O(a)-improved Wilson fermions.

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Benoit Blossier, Michele Della Morte, Patrick Fritzsch, Nicolas Garron, Jochen Heitger, Hubert Simma, Rainer Sommer, Nazario Tantalo. 2012-03-29. Parameters of Heavy Quark Effective Theory from Nf=2 lattice QCD. https://doi.org/10.1007/jhep09(2012)132

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