Skip navigation
   
 
Scholarly Communication
Contacts

Is the up-quark massless?

Irving, A.C.; McNeile, C.; Michael, C.; Sharkey, K.J. and Wittig, H. (2001) Is the up-quark massless? Physics Letters B, 518 (3-4). pp. 243-251. ISSN 0370-2693

[img]
Preview
PDF
194Kb
[img]
Preview
Postscript (Requires a viewer, such as GSview)
273Kb

Official URL: http://www.elsevier.com/wps/find/journaldescriptio...

Abstract

We report on determinations of the low-energy constants alpha5 and alpha8 in the effective chiral Lagrangian at O(p^4), using lattice simulations with N_f=2 flavours of dynamical quarks. Precise knowledge of these constants is required to test the hypothesis whether or not the up-quark is massless. Our results are obtained by studying the quark mass dependence of suitably defined ratios of pseudoscalar meson masses and matrix elements. Although comparisons with an earlier study in the quenched approximation reveal small qualitative differences in the quark mass behaviour, numerical estimates for alpha5 and alpha8 show only a weak dependence on the number of dynamical quark flavours. Our results disfavour the possibility of a massless up-quark, provided that the quark mass dependence in the physical three-flavour case is not fundamentally different from the two-flavour case studied here.

Item Type:Article
Additional Information:LTH 516. arXiv Number: arXiv:hep-lat/0107023v2. Available online 17 September 2001. Issue: 18 October 2001.
Uncontrolled Keywords:CHIRAL PERTURBATION-THEORY; ONE-LOOP ORDER; LATTICE QCD; O(A) IMPROVEMENT; QUENCHED QCD; LIGHT QUARKS; LOGARITHMS; SYMMETRY; RATIOS
Subjects:Q Science > QC Physics
Departments, Research Centres and Related Units:Academic Faculties, Institutes and Research Centres > Faculty of Science > Department of Mathematical Sciences
DOI:10.1016/S0370-2693(01)01062-0
Related URLs:
Refereed:No
Status:Published
ID Code:569
Deposited On:20 Aug 2008 09:37
Last Modified:20 Mar 2012 11:24

Repository Staff Only: item control page

   
Search


Full text only
Peer reviewed only

Browse
Cross Archive Search
Find
Top 50 authors
Top 50 items
[more statistics]
 
   

These pages are maintained by Library Staff @ University of Liverpool Library

 

All pages © The University of Liverpool, 2004 | Disclaimer | Accessibility | Staff | Students