Dual parton model

Reviews of experimental results from the polarized-beam program at the Argonne ZGS☆

Hydrodynamics of Hadronic Matter Produced in Ultrarelativistic Nucleus-nucleus Collisions

High energy nucleus-nucleus collisions in the dual parton model

In the last five years ample evidence has been found supporting the idea that the quark-parton structure of hadrons is relevant for multiple production in soft hadronic collisions. Starting from the experimental foundations, the authors compare the most successful models applying this idea. Implications are discussed on special type reactions like diffraction dissociation and collisions on nuclei, and the models are confronted with recent data leading to new insight and modifications. Relative yields of particles in the central region may be understood as reflecting their valence quark structure in the framework of quark combinatorics, and the comparison of the valence structure of initial and final hadrons allows one to understand yields in the fragmentation regions. From the structure functions of initial hadrons and/or the fragmentation functions of (di)quarks into final hadrons as seen in deep inelastic lepton-hadron or e+e- collisions, one can deduce the shape of fragmentation spectra in soft hadronic collisions. However, hadronic oscillations also prove a very rich independent source of information on parton structure. Work to be done on the theoretical side is on a solid foundation of the two successful pictures of quark fragmentation and quark recombination as well as on an explanation of their apparent complementarity. On the experimental side, apart from further results from the pp collider, high statistics is needed on hydrogen and on heavier nuclei at rho lab>200 GeV/c in particular from strange beams.

https://iopscience.iop.org/article/10.1088/0034-4885/46/11/001/pdf

Parton models of low momentum transfer processes

/pdf/multi-chain-model-for-high-energy-hadron-nucleus-collisions-50p1wtzxna.pdf

Multi-Chain Model for High Energy Hadron Nucleus Collisions

We show that effects of dibaryon resonances can be clearly seen in the data on the differential cross section of red elastic scattering. Giving the formulation of the Glauber model with the resonance formation term in red direct channel in detail and analyzing all the data presently available by this model, we find that at least two resonances are needed in red direct channel in order to explain the data. One of them may be 'F, (2. 25 GeV) state of two nucleons which was found at Argonne and the other has mass value around ~.5GeV. The data are not enough to determine the spin-parity of the latter but ()' seems somewhat preferable. The branching ratios of the resonances into red system are also given.

/pdf/elastic-pion-deuteron-scattering-and-dibaryon-resonances-25lcktnara.pdf

Elastic Pion-Deuteron Scattering and Dibaryon Resonances

Leading nucleon spectra on nuclear targets are analyzed by the multi-chain model with sequential collision of the leading cluster. It is shown that the model can successfully repro· duce both the leading particle spectra and the charged particle distribution. The inelasticity of the leading cluster turned out to be smaller than 0.2 which gives a strong constraint on any type of multiple collision models.

/pdf/leading-particle-spectra-on-nuclear-targets-and-multi-chain-21jy83io0s.pdf

Leading Particle Spectra on Nuclear Targets and Multi-Chain Model

Multiparticle Production in Particle and Nuclear Collisions-1-

As a natural extension of the multi-chain model, which reproduces the charged particle distribution in hadron-nucleus collisions in the central and projectile fragmentation regions, the cascade mechanism due to the recoil nucleon is incorporated in the model It is shown that this effect almost fills up the discrepancy observed in the target fragmentation region The influence of the multi-baryon state in the target nucleus is also examined in relation to the ratio of the charged particles produced on nuclear target to that on nucleon target

/pdf/recoil-nucleon-effect-in-the-hadron-nucleus-collision-and-4xkqsz63b6.pdf

Hiroyuki Sumiyoshi

Papers

Multi-Chain Model for High Energy Hadron Nucleus Collisions

Elastic Pion-Deuteron Scattering and Dibaryon Resonances

Leading Particle Spectra on Nuclear Targets and Multi-Chain Model

Multiparticle Production in Particle and Nuclear Collisions-1-

Recoil Nucleon Effect in the Hadron-Nucleus Collision and Multi-Chain Model