Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
8186541 | Physics Letters B | 2018 | 6 Pages |
Abstract
This letter reports a first quantitative analysis of the contribution of higher partial waves in the charge symmetry breaking reaction ddâ4HeÏ0 using the WASA-at-COSY detector setup at an excess energy of Q=60MeV. The determined differential cross section can be parametrized as dÏ/dΩ=a+bcos2â¡Î¸â, where θâ is the production angle of the pion in the center-of-mass coordinate system, and the results for the parameters are a=(1.55±0.46(stat)+0.32â0.8(syst))pb/sr and b=(13.1±2.1(stat)â2.7+1.0(syst))pb/sr. The data are compatible with vanishing p-waves and a sizable d-wave contribution. This finding should strongly constrain the contribution of the Î isobar to the ddâ4HeÏ0 reaction and is, therefore, crucial for a quantitative understanding of quark mass effects in nuclear production reactions.
Related Topics
Physical Sciences and Engineering
Physics and Astronomy
Nuclear and High Energy Physics