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arXiv · hep-ph/0107060

m_u+m_d From Isovector Pseudoscalar Sum Rules

Kim Maltman·Joachim Kambor
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Abstract

We revisit the isovector pseudoscalar sum rule determination of m_u+m_d, using families of finite energy sum rules known to be very accurately satisfied in the isovector vector channel. The sum rule constraints are sufficiently strong to allow a determination of both m_u+m_d and the excited resonance decay constants. The corresponding Borel transformed sum rules are also very well satisfied, providing a non-trivial consistency check on the treatment of direct instanton contributions. We obtain [m_u+m_d](2 GeV)=7.8\pm 1.1 MeV (in the MS bar scheme), only marginally compatible with the most recent sum rule determinations, but in good agreement with recent unquenched lattice extractions.

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Kim Maltman, Joachim Kambor. 2001-07-06. m_u+m_d From Isovector Pseudoscalar Sum Rules. https://doi.org/10.1016/s0370-2693(01)00987-x

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