, Jefferson Lab
[Host: Donal Day]
In the past two years more than 13 experiments have reported observation of a narrow exotic S=+1 baryon state in the mass range from 1.525 to 1.55 GeV/c2. The minimal quark content of this state, now called the ÃË+, is uudds. In contrast to almost fully exclusive experiments at low energies that have reported evidence for the ÃË+, there have been a number of reports of non-observation of this state, mostly in high energy inclusive experiments. The main criticisms of the reported ÃË+ signals are insufficient statistics, and variation in mass. Evidence for the doubly strange, ÃÂ¦-- (known as ÃÅ¾--),and for the charmed, ÃËc, pentaquarks have been presented only in the single experiments.
The CLAS Collaboration at Jefferson Laboratory has published two papers on the experimental evidence for the ÃË+ and ÃÅ¾--. These data now represent the world's largest data sets for photoproduction on hydrogen and deuterium. In this talk an overview of the experimental situation on the pentaquarks and the preliminary results of high statistics CLAS experiments will be presented.
Nuclear Physics Seminar
Tuesday, November 1, 2005
Physics Building, Room 204
Note special room.
To add a speaker, send an email to
Please include the seminar type (e.g. Nuclear Physics Seminars), date, name of the speaker, title of talk, and an abstract (if available).