A new framework to tune an improved relativistic heavy-quark action

Davide Giusti; Christoph Lehner

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arXiv · 2111.15614

A new framework to tune an improved relativistic heavy-quark action

Davide Giusti·Christoph Lehner

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Abstract

We introduce a new non-perturbative method to tune the parameters of the Columbia formulation of an anisotropic, clover-improved relativistic heavy-quark (RHQ) action. By making use of suitable observables which can be computed at a sequence of heavy-quark mass values, employing an $O(a)$-improved discretized action with domain-wall chiral fermion, and safely interpolated between the accessible heavy-quark mass region and the static point predicted by heavy-quark effective theory, we are able to precisely determine the unknown coefficients of the RHQ action. In this proof-of-principle study we benefit from the RBC/UKQCD Iwasaki gauge configurations with $2+1$ flavors of dynamical quarks, at three values of the lattice spacing varying from $0.11$ to $0.062$ fm. Preliminary results and applications to bottom spectroscopy are also presented.

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Davide Giusti, Christoph Lehner. 2021-11-30. A new framework to tune an improved relativistic heavy-quark action. https://arxiv.org/abs/2111.15614

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