Isospin odd πK scattering length
نویسنده
چکیده
We make use of the chiral two–loop representation of the πK scattering amplitude [J. Bijnens, P. Dhonte and P. Talavera, JHEP 0405 (2004) 036] to investigate the isospin odd scattering length at next-to-next-to-leading order in the SU(3) expansion. This scattering length is protected against contributions of m s in the chiral expansion, in the sense that the corrections to the current algebra result are of order M 2 π. In view of the planned lifetime measurement on πK atoms at CERN it is important to understand the size of these corrections.
منابع مشابه
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