Speaker
Dmitry Ryabchikov
(Institute for High Energy Physics)
Description
The COMPASS experiment, at CERN SPS, has collected the worlds largest statistics
of the reaction pi- p -> pi- pi- pi+ p - more than 5*10^7 events.
The amount and also the quality of this data sample allows for detailed
studies of 3pi partial-wave amplitudes behaviour in 2 dimentions: invariant mass m(3pi) and four momentum transfer t'.
The method of traditional mass-independent PWA with 3 body isobar model is performed in multiple m(3pi) and t' bins which is followed by mass-dependent analysis performed simultaneously in all t' slices. This makes it possible for
efficient separation between resonant and background components. The new PWA method of simultaneous optimization of 3pi isobaric amplitudes and several pi+pi- amplitudes - different for each J^PC 3pi mother state (so called "de-isobared fit") is developed and applied to the current data.
Author
Dmitry Ryabchikov
(Institute for High Energy Physics)
