Evidence for an exotic S=-2, Q=-2 baryon resonance in proton-proton collisions at the CERN SPS
Results of resonance searches in the Xi - pi -, Xi - pi +, Xi -bar+ pi -, and Xi -bar+ pi + invariant mass spectra in proton-proton collisions at sqrt[s]=17.2 GeV are presented. Evidence is shown for the existence of a narrow Xi - pi - baryon resonance with mass of 1.862±0.002 GeV/c2 and width below the detector resolution of about 0.018 GeV/c2. The significance is estimated to be above 4.2 sigma . This state is a candidate for the hypothetical exotic Xi --3/2 baryon with S=-2, I=3 / 2, and a quark content of (dsdsu-bar). At the same mass, a peak is observed in the Xi - pi + spectrum which is a candidate for the Xi 03/2 member of this isospin quartet with a quark content of (dsusd-bar). The corresponding antibaryon spectra also show enhancements at the same invariant mass.
| Author: | Christopher Alt, L. Betev, Anja Billmeier, Christoph Blume, Roland Bramm, P. Buncic, Peter Dinkelaker, Dominik Bernhard Flierl, Marek Gazdzicki, Stefan Kniege, Thorsten Kollegger, Christine Meurer, Michael Kosta Mitrovski, R. Renfordt, Reinhard Stock, Herbert Ströbele, Alexander Albert Wetzler, Jacek Zaranek, et al., NA49 Collaboration |
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| URN: | urn:nbn:de:hebis:30-19188 |
| Document Type: | Article |
| Language: | English |
| Date of Publication (online): | 14.10.2005 |
| Year of first Publication: | 2004 |
| Publishing Institution: | Univ.-Bibliothek Frankfurt am Main |
| Source: | Phys. Rev. Lett. 92, 042003 (2004), ©2004 The American Physical Society, http://link.aps.org/abstract/PRL/v92/e042003 |
| HeBIS PPN: | 191521574 |
| Institutes: | Physik |
| Dewey Decimal Classification: | 530 Physik |
| PACS-Classification: | 12.39.-x Phenomenological quark models |
| 13.75.Cs Nucleon-nucleon interactions (including antinucleons, deuterons, etc.) (for <i>N</i>-<i>N</i> interactions in nuclei, see 21.30.-x) | |
| 14.20.Jn Hyperons | |
| Sammlungen: | Universitätspublikationen |
| Licence (German): |  Veröffentlichungsvertrag für Publikationen ohne Print on Demand |
