Determination of the internal structure of valons

We determine the internal structure functions of the valons introduced by Hwa and coworkers, using low-p _t data and Regge model constraints. Our calibration reaction is the fragmentation processp→π^? observed in 70 GeV/cK ⁺ p interactions. The fitted valon structure parameters are used to make successful predictions for various other fragmentation processes (p→π⁺ andp→K ⁺). A comparison with experimental data of the DISvW ₂ (x)-values implied by this same fit, indicates that soft processes probe the nucleon typically at aQ ²-value of ～1 GeV². This finding supports the hypothesis that soft hadronic reactions are useful (and often unique) tools to learn about hadron quark structure.     

Leading particles and charged particle multiplicity in annihilation and non-annihilation interactions

Using data from our K^?p experiment at 8.25 GeV/c we have investigated the charged particle multiplicity, and the variation of charged pion multiplicity as a function of the effective mass squared of all pions, for various samples of data, and compared our results with $\text{p}$p annihilation data and pp data. Evidence is presented which suggests that the difference in behaviour between the annihilation and non-annihilation data is not due to some specific mechanism such as baryon exchange, but is related to the absence of leading particles in the former case.     

Slow proton andΔ ++ production inK + p interactions at 70 GeV/c

The inclusive inelastic processesK ⁺ p→pX ⁺ andK ⁺ p→Δ ⁺⁺ X ⁰ are studied at an incident momentum of 70 GeV/c. The data comes from the Big European Bubble Chamber BEBC filled with hydrogen, exposed to an rf reparatedK ⁺ beam at the CERN SPS accelerator. The inclusive cross section for protons with laboratory momentump _LAB≦1.2 GeV/c is equal to (6.1±0.1) mb. InclusiveΔ ⁺⁺-production is studied for |t _{p, Δ}|<1.0(GeV/c)². Comparisons are made with otherK ⁺ p data and withpp data at 69 GeV/c. Evidence is found for Pomeron exchange at the beam vertex both for slow proton andΔ ⁺⁺-production as well as for absorptive pion exchange at the (p,Δ ⁺⁺) vertex.     

The missing mass squared dependence of the average charged particle multiplicity in the reaction K+p → KoX++ from 5–16 GeV/c

The average charged particle multiplicity, 〈n_ch(M_X²)〉, in the reaction K⁺p→K^oX⁺⁺ is studied as a function of the mass squared, M_X², of the recoil system X and also as a function of the K^o transverse momentum, p_T, at incident momenta of 5.0, 8.2 and 16.0 GeV/c. The complete data samples yield distributions which are not independent of c.m. energy squared, s, They exhibit a linear dependence on log (M_X²_X/M_o²)[M_o²=1 GeV²] with a change in slope occurring for M_X²≈s/2, and do not agree with the corresponding distributions of 〈n_ch〉 as a function of s for K⁺ p inelastic scattering. Sub-samples of the data for which K^o production via beam fragmentation, central production and target fragmentation are expected to be the dominant mechanisms show that, within error, the distribution of 〈n_ch(M_X²)〉 versus M_X² is independent of incident momentum for each sub-sample separately. In particular in the beam fragmentation region the 〈n_ch(M_X²)〉 versus M_X² distribution agrees rather well with that of 〈n_ch〉 versus s for inelastic K⁺p interactions. The latter result agrees with recent results on the reactions pp → pX and π^?p → pX in the NAL energy range. Evidence is presented for the presence of different production mechanisms in these separate regions.     

Phenomenological comparison of inelastic electron-proton scattering with reaction K+ p → K0 + anything at 5, 8.2 and 16 GeV/c

We present an analysis of the reaction K⁺p → K⁰ + anything at incident momenta of 5, 8.2 and 16 GeV/c in terms of the Björken variables gw and x. Assuming dominance of ? exchange, we derive the structure function F₂(x, y) which is found similar to the one obtained in deep inelastic electroproduction.