| Autor: |
M. T. Nunez Pardo de Vera, M. Agari, Ulrich Werthenbach, R. Mizuk, L. Sozuer, Maksym Titov, H. B. Dreis, John D. Spengler, R. Wurth, S. Essenov, O. Barsukova, K. Riechmann, I. Massa, F. Khasanov, Dmitry Emeliyanov, A. Stanovnik, H. Rick, G. Medin, P. Kreuzer, A. Belkov, D. Goloubkov, B. Schwenninger, Yu.T. Kiryushin, A. Schreiner, T. Zeuner, A. Bertin, S. Keller, S. Masciocchi, D. Ressing, Y. Bagaturia, T. Zivko, Z. Zheng, A. J. Schwartz, W. Hulsbergen, T. Buran, J. Flammer, D. Pose, C. Jiang, A. Spiridonov, S. De Castro, Nicola Semprini-Cesari, Jose M Hernandez, V. Vagnoni, M. Medinnis, L. Garrido, F. Sanchez, Laura Silva, C. Stegmann, Ulrich Husemann, Roberto Spighi, P. Krizan, A. Lanyov, Mikhail Zavertyaev, F. Sciacca, M. Ispiryan, S. Prystupa, João Carvalho, A. Wurz, Laura Fabbri, S. Nowak, J. Batista, Y. Goloubkov, R. Pernack, Mauro Villa, Samo Korpar, C. Bauer, S. Shuvalov, V. Rybnikov, Pietro Faccioli, V. Aushev, S. Gradl, J.D. Hansen, T. Lohse, R. Maenner, I. Gorbounov, F. Grimaldi, S. J. Aplin, I. Tsakov, A. Zhelezov, M. Adams, B. Schwingenheuer, Y. Guilitsky, D. Peralta, M. Symalla, A. Vitale, M. Funcke, I. Vukotic, A. S. Schwarz, K. T. Knöpfle, Yuriy Pylypchenko, J. Pyrlik, Peter Buchholz, I. Golutvin, H. Fleckenstein, S. Kupper, J. Bastos, M. Feuerstack-Raible, M. Bargiotti, Y. Vassiliev, Imma Riu, A. Michetti, M. Negodaev, Mogens Dam, O. Igonkina, G. Zech, A. Golutvin, B. Bobchenko, M. Boecker, M. Ouchrif, S. Karabekyan, T. Kvaratskheliia, M. Noerenberg, B. Lewendel, B. Schmidt, J.J. Wang, M. Braeuer, D. Wegener, M. zur Nedden, J. Kessler, Antonio Sbrizzi, F. Eisele, M. Mevius, Valery Pugatch, Kwong Lau, Benedetto Giacobbe, Vladislav Balagura, Th.S. Bauer, M. Walter, W. Gradl, O. Gouchtchine, R. Muresan, T. Jagla, G. Bohm, X. Dong, Hermann Kolanoski, I. Tikhomirov, M. Starič, M. Poli, M. Bruinsma, Mikhail Danilov, H. Albrecht, N.N. Karpenko, Kendall Reeves, A. Somov, C. van Eldik, H. Deppe, K. Smirnov, B. Fominykh, Yu.V. Mikhailov, K. Ehret, D. C. Goulart, Andrej Gorišek, V. Popov, Werner Hofmann, A. Bogatyrev, R. Pestotnik, K. M. Danielsen, Massimo Piccinini, S. Solunin, L. Matchikhilian, I. Abt, V. Egorytchev, António Amorim, S. Somov, Hernan Wahlberg, I. Rostovtseva, C. B. Krauss, D. Kruecker, T. Hott, I. Belotelov, H. Kapitza, S. Xella-Hansen, A. H. Walenta, Peter Robmann, Helmut Wolters, H. Schroeder, M. Schmelling, Farid Ould-Saada, A. Pose, Marco Bruschi, R. Zimmermann, A. Aleksandrov, Hs. Subramania, Antonio Zoccoli, I. Négri, U. Uwer, Vasco Amaral, C. Cruse, J. Glaess, M. A. Pleier, C. Padilla, P. Conde, Yu. Zaitsev |
| Rok vydání: |
2004 |
| Předmět: |
|
| Zdroj: |
Physical Review Letters. 93 |
| ISSN: |
1079-7114
0031-9007 |
| Popis: |
We have searched for ${\ensuremath{\Theta}}^{+}$(1540) and ${\ensuremath{\Xi}}^{--}$(1862) pentaquark candidates in proton-inducedreactions on C, Ti, and W targets at midrapidity and $\sqrt{s}=41.6\text{ }\text{ }\mathrm{G}\mathrm{e}\mathrm{V}$. In $2\ifmmode\times\else\texttimes\fi{}{10}^{8}$ inelastic eventswe find no evidence for narrow ($\ensuremath{\sigma}\ensuremath{\approx}5\text{ }\text{ }\mathrm{M}\mathrm{e}\mathrm{V}$) signals in the ${\ensuremath{\Theta}}^{+}\ensuremath{\rightarrow}p{K}_{S}^{0}$ and ${\ensuremath{\Xi}}^{--}$$\ensuremath{\rightarrow}$${\ensuremath{\Xi}}^{\ensuremath{-}}$${\ensuremath{\pi}}^{\ensuremath{-}}$ channels; our 95% C.L. upper limits (UL) forthe inclusive production cross section times branching fraction $\mathcal{B}\text{ }d\ensuremath{\sigma}/dy{|}_{y\ensuremath{\approx}0}$ are $(4--16)\ensuremath{\mu}b/N$ for a ${\ensuremath{\Theta}}^{+}$ mass between 1521 and 1555 MeV,and $2.5\ensuremath{\mu}b/N$ for the ${\ensuremath{\Xi}}^{--}$. The UL of the yield ratio of ${\ensuremath{\Theta}}^{+}/\ensuremath{\Lambda}(1520)l(3--12)%$ is significantly lower than model predictions.Our UL of $\mathcal{B}\text{ }{\ensuremath{\Xi}}^{--}/\ensuremath{\Xi}(1530{)}^{0}l4%$ is at variance with the results that have provided the first evidencefor the ${\ensuremath{\Xi}}^{--}$. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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