Production mechanism of heavy quarks for hadron - hadron and electron - positron collisisons

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1. Confirmation of a diquark and the construction of a quark - diquark model.In order to clarify reaction mechanisms of soft hadronic processes, we adopted the cascade model and the string model whose parameters were fixed from the comparison of the model predictions with data of <e^+> + <e^-> <Forward Arrow> hadrons. Concerning the quark structure of a proton, we assume two viewpoints ; ( <i> ) three independent quarks and ( <ii> ) a single quark and a diquark. The momentum distribution of the quark (or diquark) was formulated on the basis of two viewpoints and then coupled to each hadronization model. It was found that the model with the diquark could describe fairly well all single particle distributions of P+P <Forward Arrow> hadron + X at 360 GeV/c while the model without the diquark showed large deviation from the <X_F> (Feyman variable) distributions especially for the baryon production i.e. P+P <Forward Arrow> <LAMBDA> +X, P+X, <DELTA^(++)> +X.2. The EHS experiments has provided us single particle distributions of various reaction channels. The lifetimes of charmed particles D゜, <D^> +!- <> , <LAMBDA_c> were measured Proton - nucleus collisions, i. e. p+Al and p+Au were also observed and the results were compared with the multi - chain model.3. Construction of the luminosity monitor and development of track finding algorithm for the VENUS detector of TRISTAN.