Z. Sekera

Study of the reaction K+p→ K*0 (890) Δ++ from 4.6-16.0 GeV/c

Abstract A systematic analysis is presented on the reaction K + p → K ∗0 (890) Δ ++ for nine incident momenta between 4.6–16.0 GeV/ c . Cross sections, differential cross sections and vector meson single density matrix elements are given. As a function of energy, little if any change is observed in either the shapes of the differential cross sections or in the values of the density matrix elements. The data are interpreted in terms of current ideas on t -channel exchange mechanisms.

Approach to scaling in proton fragmentation studied in the reactions K+p → π±X and K−p → π±X

Abstract Data are presented on inclusive single particle distributions in the proton fragmentation region for the reactions K + p → π ± X at 8.2 and 16 GeV/ c and K − p → π ± X at 10 and 16 GeV/ c . The energy dependence is studied and compared with the dual Regge model predictions for approach to scaling. None of the existing models is in full agreement with the data. The model of Chan and his collaborators is consistent with our results under the additional assumption of equality of vector and meson coupling constants in the p π + vertex in the Mueller diagram.

Inclusive Δ++ production in K+p interactions at 8.2 and 16 GeV/c

Abstract The reaction K + p→ Δ ++ (1236)+ anything is studied at beam momenta 8.2 and 16 GeV/ c and compared with other Δ ++ producing reactions. We find that the low-mass Δ ++ π − enhancement affects the shapes of Δ ++ inclusive distributions. The triple-Regge formula is found to be consistent with the data. Dual properties of this formula are successfully tested.

Study of the K+π− total cross section for c.m. energy up to 3.4 GeV

Abstract The reaction K + p→Δ ++ (1236) + anything is studied at a beam momentum of 16.0 GeV/ c . The total and topological cross sections for K + π − interactions are estimated by a Chew-Low extrapolation from threshold to the c.m. energy of 3.4 GeV by the maximum likelihood method.

A spin-parity analysis of the K+K+K− system produced in the reaction K+p → K+K+K−p

Abstract We present the first spin-parity analysis of the K + K + K − ) system produced in the reaction K + p → K + K + K − p, and show that the general features of this system resemble those of the (ππ + π − ) and Kπ + π − ) systems produced in the reactions π (K)p → π (K) π + π − p. There is a low mass enhancement, (47 ± 11)% of which corresponds to 1 + states decaying to Ko. At higher (K + K + K − ) masses 2 − → Kf′ becomes increasingly significant and at all masses there is a 0 − contribution of roughly 30%.

A comparison of the production of K∗ (890) in K+p and K−p interactions

Abstract Results are presented on an analysis of the reaction K + p → K ∗+ (890) p at 16 GeV/ c and compared with data at lower incident momenta and with corresponding results for the reaction K − p → K ∗− (890) p. It is found for both reactions that the energy dependence of the cross section exhibits a simple ( p − n lab behaviour.

Six- and seven-body final states in K+p interactions at 5 GeV/c

We present a study of six- and seven-body final states among the K+p interactions at 5 GeV/c incident K+ momentum. Results on cross sections, resonance and single-particle productions are given. Charge dependent angular correlations for pairs of pions occur as in pp and π+p interactions (the so called GGLP effect). In contrast, no dependence on the charge is observed in the angular correlations between kaons and pions. The influence of the production of K∗ and N∗ resonances on these angular correlations is investigated. The predictions of a multi-Regge Model (CŁA) are compared to the experimental results.

Determination of the K+π- total cross section for c.m. energy up to 1.8 GeV

Abstract The reaction K + p → Δ ++ (1236) + anything is studied at beam momentum 8.2 GeV/ c . The spin density matrix of the Δ ++ shows than one-pion exchange is dominant at low-momentum transfer. The total and topological K + π − cross sections have been determined by a Chew-Low extrapolation in the cm energy range from threshold to 1.8 GeV, using three different methods of extrapolation.

Resonance production in the reaction K+p → K0pπ+ at 5,8.25 and 16 GeV/c

We present a systematic analysis of the production of K∗+(892) and Δ++(1236) resonances in the K+p → K0pπ+ reaction at 5, 8.25 and 16 GeV/c. We have measured total cross sections, differential cross sections, density matrix elements and examined resonance production mechanisms in terms of the exchange of states with definite naturality. Some results on the reaction K+p → K∗+(1420)p are also given.

Study of the inclusive reaction K+p → K0 + anything at 5, 8.2 and 16 GeV/c in the central region

Abstract The inclusive reaction K + p → K 0 + X is studied at 5, 8.2 and 16 GeV/ c . The energy dependence and the shapes of inclusive spectra in the central region are found to be consistent with double-Regge expansion. With the values obtained for the parameters of the Regge expansion, prediction are made for the behaviour of the cross section at higher energies.