Diffractive dissociation into $K_s{K}^{\pm }{\pi }^{\mp }{\pi }^{-}$ final states

Abstract

The COMPASS fixed-target experiment at CERN/SPS is dedicated to the study of hadron structure and spectroscopy, especially the search for spin-exotic states. After having started to study the existence of the spin-exotic ${\pi }_1(1600)$ resonance in the 2004 pilot-run data, the new 2008/09 data will enable us to further clarify the situation. Apart from the ${\pi }_1(1600)$ resonance, also a spin-exotic ${\pi }_1(2000)$ was reported in the past in the $f_1(1285)\pi$ decay channel by the E852/BNL experiment, however, this state still lacks confirmation. We present a first event selection of the diffractively produced $(K\bar{K}\pi \pi {)}^{-}$ system showing clean $f_1(1285)$ and $f_1(1420)$ resonances at competing statistics. A partial-wave analysis started on $f_1(1285)\pi$ and $f_1(1420)\pi$ decay channels will further complete the search for spin-exotics in the 2008/09 COMPASS data.

4 pages, 6 figures, Hadron2011 Conference Proceedings, to appear in the proceedings of the XIV International Conference on Hadron Spectroscopy: Hadron 2011, Munich, Germany, 13-17 June 2011