abstract

The superhamiltonian and the supermomentum are constructed for the Dirac field in curved spacetime and it is shown that field dynamics and kinematics of spacelike hyper-surfaces are consistent.

abstract

The data on the interactions of cosmic nuclei with emulsion are presented. The average energy of incoming nuclei is about 19 GeV/nucleon. The cross-sections for nucleus–nucleus collisions are determined and compared with Glauber theory. The average and the dispersion of multiplicity distribution observed in nucleus–nucleus collisions are presented. They are discussed in the framework of the incoherent production model in collision of two nuclei.

abstract

The known Weisskopf–Wigner formula for decay width is derived by the Królikowski–Rzewuski formalism. All approximations made in the course of the derivation are listed.

abstract

The Additive Quark Model relates \(\Delta \) to vector meson production. The predictions of this model are formulated and compared to the data in a number of reactions involving vector mesons and \(\Delta \) production. In all cases excellent agreement with data has been found. With the quark model we generalize the vector dominance relation proposed by Cho and Sakurai to the \(\Delta \) case. Experiments agree well with the predictions. Empirically the predictions appear to be valid also in other reactions like \(A_1\) production.

abstract

We investigate general features of an effective one-particle approximation to the description of hadronic matter produced in high energy collisions. This scheme is the consequence of the assumption that particles are emitted by random fluctuating sources. The fluctuations independently of the nature of the sources lead to strong correlations possessing both short and long range components, offering thus a unified description of the clustering phenomena and of the broadening of multiplicity distributions. We show that the long range components may give rise to a limiting hadron temperature.

abstract

Careful analysis of multiplicity, one particle inclusive spectra and resonances data leads to the idea that universality of particle production in all reactions should be abandoned and replaced by the idea of universality of quark jets. Quark jets are the building blocks in constructing production amplitudes according to the rules of duality and Topological Expansion. The model we suggest can be easily and naturally interpreted in terms of colour confinement. Multiplicities in hadron and lepton induced reactions are then related.

abstract

We argue that the production of “additional” low mass muon pairs at relative level of 10\(^{-4}\)  is a universal feature of the reactions in which hadronic jets are formed. Such dimuons arise from annihilations of quarks and antiquarks created during the space-time evolution of a jet. Contributions to the production of trimuons in lepton–hadron reactions are estimated.

abstract

It is pointed out that the following two assumptions: (a) low mass dimuons produced in hadronic collisions are originated by annihilations of quarks and antiquarks created during the collision and (b) mesons produced in these collisions come from recombinations of quarks and antiquarks, imply a close similarity between the shapes of inclusive spectra of low mass dimuons and directly produced mesons. Some data corroborating such a similarity are briefly reviewed and crucial tests concerning the \(A\)-dependence of low mass dimuon production in various rapidity regions are proposed.

abstract

It is demonstrated that the known perturbation expansion, and its first diagonal Padé approximant, for the Fourier transform of the energy of two classical sources in QCD, agree approximately with the potential used in charmonium phenomenology for 0.5 GeV \(\leq q \leq \) 10 GeV. It is argued that the singularity of the exact energy at \(q =0\) is stronger than \(g^{-2}\).