An ``Improved" Lattice Study of Semi-leptonic Decays of D-Mesons

Abstract

We present results of a lattice computation of the matrix elements of the vector and axial-vector currents which are relevant for the semi-leptonic decays $D\to K$ and $D\to K^{\ast }$. The computations are performed in the quenched approximation to lattice QCD on a $24^3\times 48$ lattice at $\beta =6.2$, using an $O(a)$-improved fermionic action. In the limit of zero lepton masses the semi-leptonic decays $D\to K$ and $D\to K^{\ast }$ are described by four form factors: $f_K^{+},V,A_1$ and $A_2$, which are functions of $q^2$, where $q^{\mu }$ is the four-momentum transferred in the process. Our results for these form factors at $q^2=0$ are: $f^+_K(0)=0.67 \er{7}{8}$ , $V(0)=1.01 \err{30}{13}$ , $A_1(0)=0.70 \err{7}{10}$ , $A_2(0)=0.66 \err{10}{15}$ , which are consistent with the most recent experimental world average values. We have also determined the $q^2$ dependence of the form factors, which we find to be reasonably well described by a simple pole-dominance model. Results for other form factors, including those relevant to the decays \dpi and \drho, are also given.

arXiv comment41 pages, uuencoded compressed postscript file containing 14 figures, LaTeX, Edinburgh Preprint 94/546 and Southampton Preprint SHEP 93/94-32

References in corpus (8)

• Gauge-Invariant Smearing and Matrix Correlators using Wilson Fermions at beta=6.2
• Semi-leptonic Decays of Heavy Flavours on a Fine Grained Lattice
• Quenched Heavy-Light Decay Constants
• The Light Hadron Spectrum and Decay Constants in Quenched Lattice QCD
• Quenched Light Hadron Mass Spectrum and Decay Constants: the effects of $O(a)$-Improvement at $\beta =6.2$
• Progress in QCD Using Lattice Gauge Theory
• Current Renormalisation Constants with an O(a)-improved Fermion Action
• Heavy-light and light-light weak matrix elements on the lattice

Cited by in corpus (30)

• Lattice-Constrained Unitarity Bounds for ${\bar{B}}^0\to {\pi }^{+}{l}^{-}{\bar{\nu }}_l$ Decays
• Mixing of scalar glueballs and flavour-singlet scalar mesons
• Heavy --> Light semileptonic decays of pseudoscalar mesons from lattice QCD
• The Semileptonic Decays $B\to \pi l\nu$ and $D\to \pi l\nu$ from Lattice QCD
• Improved B -> pi l nu_l form factors from the lattice
• Lattice Study of the Decay B^0-bar -> rho^+ l^- nu_l-bar: Model-Independent Determination of |V_{ub}|
• Charmed and Bottom Baryons: a Variational Approach based on Heavy Quark Symmetry
• Study of $D^{+}\to K^{-}{\pi }^{+}{e}^{+}{\nu }_e$
• New effective treatment of the light-front nonvalence contribution in timelike exclusive processes
• Study of the leptonic decays of pseudoscalar $B,D$ and vector $B^{\ast },D^{\ast }$ mesons and of the semileptonic $B\to D$ and $B\to D^{\ast }$ decays
• Investigation of Effects of New Physics in $c\to (s,d){\ell }^{+}{\nu }_{\ell }$ Transitions
• Testing Lepton Flavour Universality with (Semi)-Leptonic $D_{(s)}$ Decays
• Analysis of D+ to K- pi+ e+ nu_e and D+ to K- pi+ mu+ nu_mu Semileptonic Decays
• Semileptonic $B\to \pi$ Decays from an Omnès Improved Nonrelativistic Constituent Quark Model
• Status of Heavy Quark Physics on the Lattice
• Measurement of the Branching Ratio B(D+ --> rho^0 l nu)/B(D+ --> K*0 l nu)
• Model Independent Measurement of Form Factors in the Decay D^+ --> K^- pi^+ e^+ nu_e
• Measurement of the form-factor ratios for D+ --> K* l nu
• |Vub| from Exclusive Semileptonic B--> rho Decays
• Heavy Quarks on the Lattice
• Form Factors for Semileptonic B -> pi and D -> pi Decays from the Omnes Representation
• First Lattice Study of the Form Factors A_0 and A_3 in the Decay Bbar^0 to rho^+ l^- nubar_l
• A Phenomenological Analysis of Non-resonant Charm Meson Decays
• Measurement of the D+ --> K*0bar l+ nu_l Branching Fraction
• Static and dynamic properties of hadronic systems with heavy quarks b and c
• Study of the semileptonic decays B->pi, D->pi and D->K
• Semi-leptonic decays of heavy mesons
• Observation of $D^{+}\to K_S^0{\pi }^0{\mu }^{+}{\nu }_{\mu }$, Test of Lepton Flavor Universality and First Angular Analysis of $D^{+}\to {\bar{K}}^{\ast }(892{)}^0{\ell }^{+}{\nu }_{\ell }$
• Calculation of f_B and the ``Isgur-Wise Function'' using a non-perturbatively improved fermion action
• B and D semileptonic decays to light mesons