Abstract
We report a search for low-lying exotic baryons via double radiative capture on pionic hydrogen. The data were collected at the TRIUMF cyclotron using the RMC spectrometer by detecting gamma-ray pairs from pion stops in liquid hydrogen. We found no evidence to support an earlier claim for exotic baryons of masses 1004 and 1044 MeV/c 2, and set upper limits on exotic baryon mediated capture of <3×10 -6 and <4×10 -6, respectively. We also obtained bounds on the couplings between exotic baryons and ordinary nucleons.
| Original language | English |
|---|---|
| Pages (from-to) | 131-138 |
| Number of pages | 8 |
| Journal | Physics Letters B |
| Volume | 597 |
| Issue number | 2 |
| DOIs | |
| State | Published - Sep 9 2004 |
| Externally published | Yes |
Funding
The authors are indebted to Profs. Yakov Azimov and Igor Strakovsky for prompting our efforts and for many valuable discussions. We wish to thank the staff of the TRIUMF laboratory for their support of this work. In particular we acknowledge the help of Dr. Renée Poutissou on the data acquisition, and Dr. Dennis Healey on the hydrogen target. In addition we thank the National Science Foundation (United States), the Natural Sciences and Engineering Research Council (Canada), the Clare Boothe Luce Foundation (JHDC), and the Jeffress Memorial Trust (DSA), for financial support.