2023 Impact factor 4.2
Particles and Fields


Eur. Phys. J. C 24, 237-243 (2002)
DOI: 10.1007/s100520200930

Light quark masses from scalar sum rules

M. Jamin1, J.A. Oller2 and A. Pich3

1  Institut für Theoretische Physik, Universität Heidelberg, Philosophenweg 16, 69120 Heidelberg, Germany
2  Departamento de Física, Universidad de Murcia, 30071 Murcia, Spain
3  Departament de Física Teòrica, IFIC, Universitat de València - CSIC, Apt. Correus 22085, 46071 València, Spain

(Received: 18 October 2001 / Revised version: 22 January 2002 / Published online: 12 April 2002 - © Springer-Verlag / Società Italiana di Fisica 2002 )

Abstract
In this work, the mass of the strange quark is calculated from QCD sum rules for the divergence of the strangeness-changing vector current. The phenomenological scalar spectral function which enters the sum rule is determined from our previous work on strangeness-changing scalar form factors [1]. For the running strange mass in the $\overline{\mathrm {MS}}$ scheme, we find $m_s(2\,{\mathrm {GeV}})=99\pm 16\,{\mathrm {MeV}}$. Making use of this result and the light quark mass ratios obtained from chiral perturbation theory, we are also able to extract the masses of the lighter quarks mu and md. We then obtain $m_u(2\,{\mathrm {GeV}})=2.9\pm 0.6\,{\mathrm {MeV}}$ and $m_d(2\,{\mathrm {GeV}})=5.2\pm 0.9\,{\mathrm {MeV}}$. In addition, we present an updated value for the light quark condensate.



© Società Italiana di Fisica, Springer-Verlag 2002