A RESONANCE IN THE Lambda pi SYSTEM
The authors report a study of the reaction K{sup -} + p {yields} {Lambda}{sup 0} + {pi}{sup +} + {pi}{sup -} produced by 1.15 Gev/c K{sup -} mesons and observed in the Lawrence Radiation Laboratory's 15-in. hydrogen bubble chamber. A preliminary report of these results was presented at the 1960 Rochester Conference. The beam was purified by two velocity spectrometers. A hyperon/observed during the run and the preliminary cross sections for various K{sup -} reactions at 1.15 Bev/c have been reported previously. Reaction (1) was the first one selected for detailed study, because it appeared to take place with relatively large probability and because the event, a 2-prong interaction accompanied by a V, was easily identified. In a volume of the chamber sufficiently restricted so that the scanning efficiency was near 100%, 255 such events were found. These events were measured, and the track data supplied to a computer which tested each event for goodness of fit to various kinematic hypotheses. The possible reactions, the distribution of events, and the corresponding cross sections are given in Table I. An event was placed in a given category of Table I if the {chi}{sup 2} probability for the other hypotheses was < 1%. It appears likely that the majority of the events in group(e) are also reactions of type (I). This belief is based on the following arguments: (1) since the kinematics of a {Lambda} {pi}{pi} fit (four constraints) are more overdetermined than those of a {Sigma}{sup 0} {pi}{pi} fit(two constraints), it is relatively easy for a {Lambda} {pi}{pi} reaction to fit a {Sigma}{sup 0} {pi}{pi} reaction, but only very few {Sigma}{sup 0} configurations can fit the {Lambda} {pi}{pi} reactions. (2) The events of group(e) when treated as {Sigma}{sup 0} {pi}{pi} reactions give a {chi}{sup 2} distribution which is much worse than that obtained when they are treated as {Lambda} {pi}{pi} reactions.
- Research Organization:
- Ernest Orlando Lawrence Berkeley National Laboratory, Berkeley, CA (US)
- Sponsoring Organization:
- USAEC
- DOE Contract Number:
- W-7405-ENG-48; AC02-05CH11231
- OSTI ID:
- 928504
- Report Number(s):
- UCRL--9456
- Country of Publication:
- United States
- Language:
- English
Similar Records
K$sup -$p INTERACTIONS AT 1.15 Bev/c
Phi meson and accompanying strange particle production in 16 GeV/c. pi. /sup +/p interactions. Final report