Abstract
The π+ π- atom decays - in the ground state - predominantly into two neutral pions. We present a general expression for the corresponding decay width in the framework of QCD (including photons). It contains all terms at leading and next-to-leading order in isospin breaking. The result allows one to evaluate the combination |α0 - α2| of ππ S-wave scattering lengths from π+π- lifetime measurements, like the one presently performed by the DIRAC experiment at CERN.
Original language | English |
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Pages (from-to) | 335-340 |
Number of pages | 6 |
Journal | Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics |
Volume | 462 |
Issue number | 3-4 |
DOIs | |
Publication status | Published - 1999 |
Keywords
- Chiral perturbation theory
- Hadronic atoms
- Nonrelativistic effective Lagrangians
ASJC Scopus subject areas
- Nuclear and High Energy Physics