Heavy-Light Semileptonic Decays in Staggered Chiral Perturbation Theory

Abstract

We calculate the form factors for the semileptonic decays of heavy-light pseudoscalar mesons in partially quenched staggered chiral perturbation theory (\schpt), working to leading order in $1/m_Q$, where $m_Q$ is the heavy quark mass. We take the light meson in the final state to be a pseudoscalar corresponding to the exact chiral symmetry of staggered quarks. The treatment assumes the validity of the standard prescription for representing the staggered ``fourth root trick'' within \schpt by insertions of factors of 1/4 for each sea quark loop. Our calculation is based on an existing partially quenched continuum chiral perturbation theory calculation with degenerate sea quarks by Becirevic, Prelovsek and Zupan, which we generalize to the staggered (and non-degenerate) case. As a by-product, we obtain the continuum partially quenched results with non-degenerate sea quarks. We analyze the effects of non-leading chiral terms, and find a relation among the coefficients governing the analytic valence mass dependence at this order. Our results are useful in analyzing lattice computations of form factors $B\to \pi$ and $D\to K$ when the light quarks are simulated with the staggered action.

53 pages, 8 figures, v2: Minor correction to the section on finite volume effects, and typos fixed. Version to be published in Phys. Rev. D

References in corpus (5)

• Staggered Chiral Perturbation Theory and the Fourth-Root Trick
• Observations on staggered fermions at non-zero lattice spacing
• Renormalization-group analysis of the validity of staggered-fermion QCD with the fourth-root recipe
• Lattice fermions with complex mass
• Validity of the Rooted Staggered Determinant in the continuum limit

Cited by in corpus (12)

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• The B -> pi l nu semileptonic form factor from three-flavor lattice QCD: A model-independent determination of |V(ub)|
• $D\to K,l\nu$ Semileptonic Decay Scalar Form Factor and $|V_{cs}|$ from Lattice QCD
• Visualization of semileptonic form factors from lattice QCD
• D-meson semileptonic decays to pseudoscalars from four-flavor lattice QCD
• Exclusive semileptonic $B_s\to K\ell \nu$ decays on the lattice
• Semileptonic decays of K and D mesons in 2+1 flavor QCD
• Lattice Calculations of B to K/K*l+l- form factors
• Quark Flavor Physics Review
• $B$-meson semileptonic form factors on (2+1+1)-flavor HISQ ensembles
• Staggered Chiral Perturbation Theory for Neutral B Mixing