Back to Search
Start Over
First measurement of chiral dynamics in π- γ → π- π- π+.
- Source :
-
Physical review letters [Phys Rev Lett] 2012 May 11; Vol. 108 (19), pp. 192001. Date of Electronic Publication: 2012 May 11. - Publication Year :
- 2012
-
Abstract
- The COMPASS Collaboration at CERN has investigated the π- γ → π- π- π+ reaction at center-of-momentum energy below five pion masses, sqrt[s]<5m(π), embedded in the Primakoff reaction of 190 GeV pions impinging on a lead target. Exchange of quasireal photons is selected by isolating the sharp Coulomb peak observed at smallest momentum transfers, t'<0.001 GeV2/c2. Using partial-wave analysis techniques, the scattering intensity of Coulomb production described in terms of chiral dynamics and its dependence on the 3π-invariant mass m(3π)=sqrt[s] were extracted. The absolute cross section was determined in seven bins of sqrt[s] with an overall precision of 20%. At leading order, the result is found to be in good agreement with the prediction of chiral perturbation theory over the whole energy range investigated.
Details
- Language :
- English
- ISSN :
- 1079-7114
- Volume :
- 108
- Issue :
- 19
- Database :
- MEDLINE
- Journal :
- Physical review letters
- Publication Type :
- Academic Journal
- Accession number :
- 23003028
- Full Text :
- https://doi.org/10.1103/PhysRevLett.108.192001