The light scalars, especially the sigma, in charm decay and elsewhere
| dc.creator | Tornqvist, N. A. | |
| dc.creator | Polosa, A. D. | |
| dc.date | 2000-11-08 | |
| dc.date.accessioned | 2026-07-07T03:43:11Z | |
| dc.date.available | 2026-07-07T03:43:11Z | |
| dc.description | We discuss how the lightest scalars, in particular the broad sigma resonance, can be understood as unitarized (qbar q) states within a unitarized quark model (UQM). The bare (qbar q) scalars are strongly distorted by hadronic mass shifts, and the (ubar u+ dbar d) state becomes a very broad resonance, with its pole at 470-i250 MeV. This is the sigma meson required by models for spontaneous breaking of chiral symmetry. We also discuss the less well known phenomenon that with a large coupling there can appear two physical resonance poles on the second sheet although only one bare quark-antiquark state is put in. The f_0(980) and f_0(1370) resonance poles can thus be two manifestations of the same (sbar s) quark state. Both of these are dominant in the E791 Dalitz plot of D_s-> 3pi, where (sbar s) intermediate states should be dominant. Recently this light sigma has clearly been observed in D-> sigma pi-> 3pi by the E791 experiment at Fermilab. We discuss how this decay channel can be predicted in a Constituent Quark Meson Model (CQM), which incorporates heavy quark and chiral symmetries. | |
| dc.description | 14 pages; Invited plenary talk by N.A. Tornqvist at the ''Heavy Quark at Fixed Target'' Conference in Rio de Janeiro, Brazil, October 9-12, 2000. To appear in Frascati Physics Series | |
| dc.identifier | https://arxiv.org/abs/hep-ph/0011107 | |
| dc.identifier | http://arxiv.org/abs/hep-ph/0011107 | |
| dc.identifier | Frascati Phys.Ser. 20 (2000) 385-399 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/40127 | |
| dc.subject | High Energy Physics - Phenomenology | |
| dc.title | The light scalars, especially the sigma, in charm decay and elsewhere | |
| dc.type | text |