Publication at Faculty of Mathematics and Physics |
2018
Abstract
We present a new amplitude analysis of the eta pi D-wave in the reaction pi(-) p -> eta pi(-) p measured by COMPASS. Employing an analytical model based on the principles of the relativistic S-matrix, we find two resonances that can be identified with the a(2)(1320) and the excited a(2)(1700), and perform a comprehensive analysis of their pole positions.
For the mass and width of the a(2) we find M = (1307 +/- 1 6) MeV and Gamma=(112 +/- 1 +/- 8) MeV, and for the excited state a(2)' we obtain M = (1720 +/- 10 +/- 60) MeV and Gamma = (280 +/- 10 +/- 70) MeV, respectively. (C) 2018 The Author(s). Published by Elsevier B.V.