A model for inclusive production from high-energy hadron-nucleus interactions

It is shown that all aspects of the data on inclusive single-particle production from nuclei can be understood in terms of a model in which the interaction with the nucleus occurs through one or more elastic q-q scatterings. Successive scatters areassumeed to be mostly incoherent. No cascading occurs because “dressing” of the scattered quarks does not take place until after the quarks leave the nucleus.     

The nuclear response in high-energy hadron-nucleus interactions

In an experiment at the CERN Super Proton Synchrotron (SPS) studying hadron-nucleus interactions, slow particles which are mainly knockout protons were measured with an electronic detector. Their dependence on the target mass, incoming energy, and projectile is shown. We discuss the use of the number of protons as a measure for the number of interactions of the projectile and conclude that the emitted protons measure the impact parameter of the reaction.     

Production of cumulative protons in high-energy hadron-nucleus and nucleus-nucleus interactions

Under conditions of 4π coverage, the production of cumulative protons in π ^?C, pC, ⁴HeC, and CC collisions at high energies is studied on the basis of a large statistical sample. The behavior of inclusive cross sections for cumulative-proton production versus the cumulative number β is found to be universal in the sense that it is independent of the type projectile and primary energy. It is established that the mean number of cumulative protons is also independent of the projectile type and primary energy.     

Deuteron production and space-time characteristics of high-energy hadron-nucleus reactions

The contribution of the coalescence mechanism to deuteron production is discussed on the basis of data on inclusive deuteron and proton production in hadron-nucleus interactions. The angular dependence and theA dependence of the coefficient of twonucleon coalescence into a deuteron are analysed for 7.5 GeV/c pA and 5 GeV/cπ ^? A interactions. The results suggest an elongated shape of the interaction region along the trajectory of the incident hadron and a successive knock-out of nucleons during propagation of the incident particle through a nucleus.     

The energy and angular spectra of grey particles in high-energy hadron-nucleus interactions

A simple Monte Carlo model giving energy and angular spectra of the knocked out nucleons in the high energy hadron-nucleus interactions is described. The only input of the approach consists of some constants from the nuclear and high energy hadron-hadron phenomenology and without any adjustable parameters the model well reproduces substantial features of the experimental data.     

On the production processes of gray particles in high-energy hadron-nucleus collisions

The probability distribution for the collision number of the primary particle ν and the number of gray particles is formulated in the framework of the leading particle cascade model. Rescattering effects of the recoil nucleons are taken into consideration in our formalism on the analogy of the birth and death problem in stochastic processes. Comparison of our model with the experimental data and some discussions about the production processes of shower particles and ν are made.     

Particle production in hadron-nucleus collisions in a multi-chain fragmentation model

Zeitschrift für Physik C Particles and Fields - We investigate a multi-chain fragmentation model for particle production in hadron-hardon and hadron-nucleus collisions for all kinds of...     

On the mechanisms of cumulative-proton production in high-energy hadron-nucleus and nucleus-nucleus collisions

Physics of Atomic Nuclei -     

EMC effect and breaking of additivity of nucleons in the high-energy hadron-nucleus interactions

The EMC effect implies a strong violation of additivity of nucleons in the absorption of virtual photons by atomic nuclei. In this paper we analyze the experimental data on the hadron-nuclei interaction cross sections in search for similar effects in the scattering of hadrons on nuclei. Specifically, we look for deviations from predictions of the multiple scattering theory. We formulate, and make extensive use of the Glauber-Bribov universality of the hadron-nucleus interaction cross sections, which makes it possible to check in a unique way a consistency of the experimental data on the total, inelastic and absorption cross sections for all the incident hadrons. We find evidence for the effective cross section of interaction with bound nucleons being 5–15% larger than with free nucleons. We comment on implications of this observation for models of the EMC effect.     

Particle production in hadron-nucleus collisions at 100 GeV from a parton-string model

We calculate the inclusive momentum distribution of particles produced in a hadron-nucleus (hA) collision. The exchange of colour between the projectile and target nucleons leads to the formation of colour strings which are assumed to fragment like strings formed in deep inelastic lepton-nucleon scattering. Making a few basic hypotheses we consistently and parameterfree describe the projectile fragmentation region in collisions of the typehA→h′X withh=p, π⁺ andh′=p, π⁺, π^? at 100 GeV incident energy.     

Long-range correlations in hadron-nucleus interactions

An analysis of correlations in rapidity of charged particles produced in proton and antiproton interactions on hydrogen, argon and xenon at 200 GeV is presented. Positive long-range correlations are observed in interactions on heavy targets. The dependence of rapidity correlations between the forward and backward hemisphere on the number of projectile collisions is discussed.     

Inclusive two-and three-particle rapidity correlations in high-energy hadron-nucleus collisions

Three-particle pseudorapidity correlations are investigated for relativistic secondaries from proton-nucleus interactions at 50, 67, 200 and 400 GeV/c and from pion-nucleus interactions at 50 and 200 GeV/c. The experimental data on two- and three-particle correlations are compared with quantitative predictions of current multiple scattering models of nuclear production. Within these models the influence of various factors on the magnitude of correlations is discussed and it is shown, in particular, that energy-momentum conservation plays an essential role at present accelerator energies.     

Multiplicities in highp t hadron-nucleus interactions

We present results obtained in π^? A (A=C, Cu, Pb) — collisions at 38 GeV/c. A single particle trigger selects events with one charged particle in the central region and large transverse momentum. The effect of this trigger on the multiplicities of all charged particles and of protons is shown.     

The distribution of grey particles in very high-energy hadron-nucleus collisions

On its passage through the nucleus a very high-energy hadron strikes several target nucleons. These recoil nucleons initiate an intranuclear cascade. “Grey particles”, mostly protons with energy between 40 and 400 MeV result from the cascade. We can describe the mean number and distribution of grey particles by truncating the intranuclear cascade after the second generation. The number N_g of grey particles is very simply related to the number ν of initial hadron-nucleon collisions: , where a is a numerical constant close to 1.