Vector Meson Radiative Decay in Lattice QCD
Author : Triumf
Publisher :
Page : 6 pages
File Size : 31,53 MB
Release : 1986
Category :
ISBN :
Author : Triumf
Publisher :
Page : 6 pages
File Size : 31,53 MB
Release : 1986
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ISBN :
Author : Gordon Donald
Publisher :
Page : 135 pages
File Size : 13,86 MB
Release : 2013
Category : Fermions
ISBN :
Author : Maysam Emadi
Publisher :
Page : 171 pages
File Size : 19,71 MB
Release : 2015
Category :
ISBN :
In this thesis we use the highly improved staggered quark (HISQ) formalism to study the radiative and pionic transitions of charmed mesons within the framework of lattice QCD. The HISQ action is one of the most accurate formulations of charm quarks and is a result of a perturbative Symanzik improvement program to reduce lattice discretization errors. Decay widths are calculated in numerical simulations on an ensemble of gauge field configurations with $N_f=2+1$ asqtad sea quarks generated by the MILC collaboration. In addition we study $H_ŝ\ast$ and charmonium radiative decays as well as meson electric form factors. Experimental measurements of the decay ratios of vector charmed $D̂{\ast\pm0}$ and charmed strange $D_ŝ{\ast\pm}$ mesons, show a few curious features that are of great phenomenological interest in the study of low energy hadronic physics. Unlike most mesons, the strong hadronic decay modes of $D̂{\ast0}$ and $D_ŝ{\ast\pm}$, are not dominant. However, while the neutral $D$ has a radiative mode that is competitive with its pionic mode, the charged $D$ meson's radiative decay is highly suppressed relative to that of the neutral. This suppression provides a detailed probe of strong interactions and is apparently due to an interesting near cancellation that takes place between the photon's coupling to the charm quark and to the down antiquark. The results are in agreement with all of the available experimental data, and in particular, we show that the HISQ action successfully accounts for the near cancellation of the charmed $D̂{\ast\pm}$ radiative decay. The relative suppression is demonstrated in our result for the ratio of the radiative form factors of $D$ mesons $V̂\pm(0)/V̂0(0)=0.126(36)$ computed at heavier than physical $u/d$ quark masses. The quoted errors are purely statistical. Evidence from other lattice studies indicate small systematic errors in continuum and sea quark chiral extrapolations. Valence quark chiral extrapolation increases our errors by about 50\%. A rough extrapolation suggests an agreement with the measured radiative width within $2\sigma$.
Author : Andreas W Schreiber
Publisher : World Scientific
Page : 325 pages
File Size : 27,69 MB
Release : 2000-10-25
Category :
ISBN : 9814542849
This volume contains the proceedings of the 'Workshop on Lightcone QCD and Nonperturbative Hadron Physics', held in Adelaide, Australia, in December 1999. The contributions include papers on vacuum structure and zero modes, DLCQ, deep inelastic scattering, lightcone wavefunctions and hadron structure, hadron phenomenology, as well as numerical results from the lattice for both quenched and unquenched QCD.
Author : S. Aoki
Publisher :
Page : 10 pages
File Size : 13,50 MB
Release : 1997
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Author : Aneesh V. Manohar
Publisher : Cambridge University Press
Page : 205 pages
File Size : 50,64 MB
Release : 2023-07-31
Category : Science
ISBN : 1009402145
Author :
Publisher :
Page : pages
File Size : 47,78 MB
Release : 2014
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Author :
Publisher :
Page : 640 pages
File Size : 45,59 MB
Release : 1993
Category : Particles (Nuclear physics)
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Author : Philippe Boucaud
Publisher :
Page : 0 pages
File Size : 10,20 MB
Release : 1988
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We present the results of the first computation on large lattices of the B-meson binding energy and decay constant following the method proposed by Eichten. The results obtained at ß = 6 on a 20*102*40 lattice and at ß = 6.2 on a 163*48 lattice show that it is necessary to have a statistical sample which is much larger than in similar computations with light mesons in order to obtain results of comparable precision.
Author :
Publisher :
Page : pages
File Size : 36,75 MB
Release : 2000
Category :
ISBN :
The decay constants of B and D mesons are computed in quenched lattice QCD at two different values of the coupling. The action and operators are? (a) improved with non-perturbative coefficients where available. The results and systematic errors are discussed in detail. Results for vector decay constants, flavour symmetry breaking ratios of decay constants, the pseudoscalar-vector mass splitting and D meson masses are also presented.