Meson spectroscopy at VES and COMPASS

Dmitry Ryabchikov

doi:10.1051/epjconf/201921203010

EPJ

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Proceedings

Open Access

EPJ Web of Conferences 212, 03010 (2019)
https://doi.org/10.1051/epjconf/201921203010

Meson spectroscopy at VES and COMPASS

Dmitry Ryabchikov¹^,2^* for the VES group and the COMPASS collaboration

¹ NRC Kurchatov Institute, IHEP, Protvino, Russia
² Technical University of Muenchen, Garching, Germany

^* e-mail: Dmitry.Ryabchikov@ihep.ru

Published online: 17 June 2019

Abstract

Diffractive production of π^- π^- π⁺ and π^- π⁰ π⁰ final states is the subject of comprehensive studies performed recently by the VES and the COM-PASS experiments. COMPASS pioneered the application of novel methods of partial-wave analysis: mass-independent PWA inmultiple (m_3π, t’)-cells, mass-dependent analysis of spin-density matrices performed simultaneously in all measured t’ bins, the analysis with freed shapes of π⁺ π^- isobars. In addition, COMPASS observed a new narrow state: a₁(1420). VES has world-leading data samples on π^- π^- π⁺ and π^- π⁰ π⁰, that yield compatible results and show the potential for a detailed comparison of isospin relations between different decay channels, using the PWA methods with fixed and freed shapes of ππ isobars.

© The Authors, published by EDP Sciences, 2019

This is an open access article distributed under the terms of the Creative Commons Attribution License 4.0 (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.