Moments of light-meson distribution amplitudes from lattice QCD
Moments of light-meson distribution amplitudes from lattice QCD
The distribution amplitudes of mesons parameterize their structure in partonic terms, at least insofar as that structure is relevant to collinearly-factprized exclusive processes: they essen- tially describe the valence Fock state's momentum distribution. Early applications were to form factors such as F%m(Q2) and Frrn(Q2), but the development of QCD factorization and the Soft Collinear Effective Theory has led to renewed interest motivated by flavour physics. The lowest moments of the distribution amplitudes can be calculated using Lattice QCD. As part of the UKQCD/RBC collaborations' Nf = 2+1 domain-wall fermion phenomenology programme, we calculate the first two moments for the pseudoscalar mesons % and K and the (longitudinally-polarized) vector mesons p, K* and </>, as well as the ratios of vector meson couplings fp /fp, fx*/fK* and fl/fy. We obtain the desired quantities with a good precision and our results are in reasonable agreement with other recent lattice and QCD sum rule calcu- lations (but with significantly smaller errors in the latter case). In particular, we are able clearly to discern the expected quark-mass dependence of SU(3) flavour breaking effects. An important part of this research programme is the non-perturbative renormalization of lattice operators using the RI/MOM technique. We describe both our successful renormaliza- tion of the quark bilinears (necessary for the vector meson couplings) and our ongoing efforts to overcome some fundamental issues with RI/MOM which currently prevent us from using non-perturbative renormalization for the distribution amplitude moments.
University of Southampton
Donnellan, Michael Anthony
2008
Donnellan, Michael Anthony
Donnellan, Michael Anthony
(2008)
Moments of light-meson distribution amplitudes from lattice QCD.
University of Southampton, Doctoral Thesis.
Record type:
Thesis
(Doctoral)
Abstract
The distribution amplitudes of mesons parameterize their structure in partonic terms, at least insofar as that structure is relevant to collinearly-factprized exclusive processes: they essen- tially describe the valence Fock state's momentum distribution. Early applications were to form factors such as F%m(Q2) and Frrn(Q2), but the development of QCD factorization and the Soft Collinear Effective Theory has led to renewed interest motivated by flavour physics. The lowest moments of the distribution amplitudes can be calculated using Lattice QCD. As part of the UKQCD/RBC collaborations' Nf = 2+1 domain-wall fermion phenomenology programme, we calculate the first two moments for the pseudoscalar mesons % and K and the (longitudinally-polarized) vector mesons p, K* and </>, as well as the ratios of vector meson couplings fp /fp, fx*/fK* and fl/fy. We obtain the desired quantities with a good precision and our results are in reasonable agreement with other recent lattice and QCD sum rule calcu- lations (but with significantly smaller errors in the latter case). In particular, we are able clearly to discern the expected quark-mass dependence of SU(3) flavour breaking effects. An important part of this research programme is the non-perturbative renormalization of lattice operators using the RI/MOM technique. We describe both our successful renormaliza- tion of the quark bilinears (necessary for the vector meson couplings) and our ongoing efforts to overcome some fundamental issues with RI/MOM which currently prevent us from using non-perturbative renormalization for the distribution amplitude moments.
Text
1239671.pdf
- Version of Record
More information
Published date: 2008
Identifiers
Local EPrints ID: 466650
URI: http://eprints.soton.ac.uk/id/eprint/466650
PURE UUID: 37bb65ea-92b3-482f-a392-b0264fbbab2b
Catalogue record
Date deposited: 05 Jul 2022 06:14
Last modified: 05 Jul 2022 06:14
Export record
Contributors
Author:
Michael Anthony Donnellan
Download statistics
Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.
View more statistics