Abstract
In-medium pion-pion correlations were studied via their effect on experimental observables measured for the reaction in nuclei , and and in deuterium, from which it is inferred the observables for the nucleon n and . The measurements were performed at TRIUMF using a positive-pion flux with a bombarding energy of 283 MeV. The invariant mass distributions were measured from the threshold up to the kinematic maximum, and total cross sections deduced. The medium modifications were investigated by forming the composite ratio which proved to be only weakly affected by the reaction mechanism. In the channel the distributions are peaked at the threshold and increases with A. For pion pairs in the channel the distributions are nearly independent of A. The distinctive behavior of may be related to the appearance of the σ meson.
- Received 10 December 1998
DOI:https://doi.org/10.1103/PhysRevC.60.018201
©1999 American Physical Society