For the first time, the reaction gamma d ->Lambda nK(+) has been analyzed in order to search for the exotic pentaquark baryon Theta(+)(1540). The data were taken at Jefferson Laboratory, using the Hall-B tagged-photon beam of energy between 0.8 and 3.6 GeV and the CEBAF Large Acceptance Spectrometer (CLAS). No statistically significant structures were observed in the nK(+) invariant-mass distribution. The upper limit on the gamma d ->Lambda Theta(+) integrated cross section has been calculated and found to be between 5 and 25 nb, depending on the production model assumed. The upper limit on the differential cross section is also reported.
SEARCH FOR THE THETA+ PENTAQUARK IN THE GAMMA D ---> LAMBDA N K+ REACTION MEASURED WITH CLAS
RICCO, GIOVANNI;TAIUTI, MAURO GINO;
2006-01-01
Abstract
For the first time, the reaction gamma d ->Lambda nK(+) has been analyzed in order to search for the exotic pentaquark baryon Theta(+)(1540). The data were taken at Jefferson Laboratory, using the Hall-B tagged-photon beam of energy between 0.8 and 3.6 GeV and the CEBAF Large Acceptance Spectrometer (CLAS). No statistically significant structures were observed in the nK(+) invariant-mass distribution. The upper limit on the gamma d ->Lambda Theta(+) integrated cross section has been calculated and found to be between 5 and 25 nb, depending on the production model assumed. The upper limit on the differential cross section is also reported.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.