J. W. Waters

A new measurement of Σ+ → pγ decay properties☆

Abstract In an experiment performed at the CERN PS using the HYperon BUbble Chamber (HYBUC), we have measured the asymmetry parameter αγ for the decay Σ+→pγ. The result is αγ = −0.53+0.38−0.36 For the branching ratio we find Γ(Σ + → p γ) Γ(Σ + → p π 0 ) = (2.11 ± 0.38) × 10 −3 .

Study of the missing-mass spectra in the reactions π−d → K+ + MM and K−d → π+ + MM at 1.4 GeV/c to search for strange dibaryon states

Abstract The reactions π − d → K + + MM and K − d → π + + MM have been studied at 1.4 GeV / c to search for strange dibaryon states with quantum numbers Q = −1, and S = −1. No structures are found which could indicate the production of such states and upper limits for the cross sections are established.

Observation of the Cabibbo-suppressed decay D±→φπ±

Abstract We observe the Cabibbo-suppressed decay D ± → φπ ± in pN interaction at 400 GeV c incident proton momentum. No evidence for F ± → φπ ± decays is seen.

Observation of massive ΛKs0π+π+π−− events above 5 GeVc2

Abstract In an experiment using the Fermilab Multiparticle Spectrometer we have studied forward production of high mass events containing two strange particles and charged pions. In the final state ΛK s 0 π + π + π − π − we observe 5 events with effective mass above 5.5 GeV/ c 2 . Four of these events cluster near 5.75 GeV/ c 2 , and three of these events contain K s 0 π + π − mass combinations consistent with the charmed D 0 .

Observation of phiK pi decay of the K

We have studied inclusive pN..-->..K-/sup +/K/sup -/K/sup +/K/sup -/X final states at 400 GeV/c and present here evidence for K/sup *//sup 0/(2060)..-->..phiK/sup +-/..pi../sup minus-or-plus/ and phiK-italic/sup *//sup 0/(890). .AE

K∗±(892) Production in π−N interactions at 200 GeV/c

Abstract K ∗± (892) production is studied in the reaction π − N → K S 0 K S 0 + X where X includes up to five observed charged particles. An excess of K ∗− over K ∗+ is observed for Feynman- x > 0.1. The ratio of K ∗+ to K ∗− decreases with x as predicted by QCD counting rules. K S 0 and K ∗ production are compared to recent D and D ∗ data from other experiments.

Diffractive production of K/sub S//sup 0/K/sub S//sup 0/. pi. /sup +/. pi. /sup -/. pi. /sup -/ in. pi. /sup -/N interactions at 200 GeV/c

The diffractive dissociation of a 200-GeV/c ..pi../sup -/ beam into K/sub S//sup 0/K/sub S//sup 0/..pi../sup +/..pi../sup -/..pi../sup -/ has been observed. The diffractive K/sub S//sup 0/K/sub S//sup 0/..pi../sup +/..pi../sup -/..pi../sup -/ cross section is 1.59 +- 0.78 ..mu..b. The ratio of the diffractive K/sub S//sup 0/K/sub S//sup 0/..pi../sup +/..pi../sup -/..pi../sup -/ cross section to the diffractive K/sub S//sup 0/K/sub S//sup 0/..pi../sup -/ cross section is 0.40 +- 0.13, which is in good agreement with a diffractive-fragmentation-model prediction of 0.36. There is evidence for simultaneous production of K/sup asterisk-/ and K/sup asterisk+/ in the diffractive K/sub S//sup 0/K/sub S//sup 0/..pi../sup +/..pi../sup -/..pi../sup -/ sample. The K/sup asterisk+-/K/sub S//sup 0/..pi../sup - +/ mass distribution shows an enhancement near 1.95 GeV.

Search for Strange Dibaryon Systems (Rome-Saclay-Vanderbilt Collaboration)

In this paper preliminary results of an experiment, which is being run at the CERN Proton Synchrotron (PS) since May 1979, are reported.

Inclusive V/sup 0/ and. gamma. production in pd interactions at 18 GeV/c. [Cross sections]

Inclusive cross sections are presented for ..gamma.., K/sup 0//sub S/, and ..lambda.. particles produced by pd interactions at 18 GeV/c. Approximate cross sections are given for Lambda-bar. The data are separated into neutronlike and protonlike samples.