1996/10/17 by Sergei Bashinsky, S. V. Bashinsky, Bashinsky, S. V. +2
Physics and Astronomy · #Cold Atom Physics and Bose-Einstein Condensates #hep-ph
paper · pdf · doi:10.48550/arxiv.hep-ph/9610395
18 pages, 4 figures, RevTeX, uses aps.sty, fps.sty, see also the publication Nucl.Phys.A625:167-191,1997
arxiv created 1996/10/17 · arxiv updated 2009/11/30
We reduce the problem of many-channel hadron scattering at nonrelativistic energies to calculations on the scale of a few fermis. Having thus disentangled kinematics from interior quark dynamics, we study their interplay when a quark state occurs near a hadronic threshold. Characteristic parameters, such as the observed peak width, the decay width, and the shape of a cross-section itself are highly affected by the threshold. A general pole-form expression for the S-matrix in an arbitrary background is given, and the pole structure of S is examined. We show that at a hadronic threshold two poles in S are generally important. We also classify the S-matrix pole structure considering an example where nonsingular coupled channels are closed at the threshold. The framework of our paper is the P-matrix formalism, which is reviewed and extended for use together with conventional methods of computing quark-gluon dynamics. Results and applications are illustrated for the doubly strange two-baryon system, the detailed analysis of which we postpone till our forthcoming paper.