abstract

Using results concerning the algebraic classification of curvature quantities in complex and real space-times (Acta Phys. Pol. B 10, 485 (1979)) a sequence of generalizations of Goldberg–Sachs Theorem is enumerated.

abstract

It is argued that the electric charge \(e^{\prime } = 47\pi /e\), where \(e\) is the charge of the electron, plays a distinguished role, similar to the role of Dirac’s magnetic charge \(g = 1/2e\).

abstract

Experimental data on inelastic meson and nucleon interactions with nuclei have been analyzed within the framework of the internuclear cascade model to distinguish the points, where it disagrees with the experiment and requires further improvement. For nuclei with the mass number \(A \lesssim 15\) the discrepancies with the experiment become considerable at energies \(T \gtrsim 100\) GeV. For nuclei with \(A \simeq 100\) the discrepancies begin to appear already at \(T \lesssim 10\)–15 GeV. However, the deviations are such that at least in the energy region \(T \lesssim 100\) GeV one may hope to overcome them without introduction of any essentially new mechanisms of hadron–hadron interaction, by means of further improving the cascade model only.

abstract

Mass relations among the charmed and uncharmed baryons predicted in the quark models are derived in the framework of SU(8) symmetry. Higher order effects and spin triplet mass breaking interactions are studied.

abstract

In this note a method for the consistency checks on the spin assignment for the non-diffractive mesons of well defined \(G\) parities has been discussed. This method rules out the values 1 and 2 for the spins of the \(\chi \)(3510) and \(\chi \)(3555), respectively, suggested by the SLAC-LBL group and confirms the value 0 for the spin of the \(\chi \)(3415) also suggested by the same group. it has also been shown that all the \(\chi \)-particles so far observed must be spin-zero mesons.

abstract

Quark fragmentation functions are extracted from a Monte Carlo quark–parton model of multiparticle production in e\(^+\)e\(^-\) annihilation. Scale breaking due to transverse momenta and masses of quarks is taken into account. The model leads asymptotically to the retention of electric and baryonic charges of quarks.

abstract

The branching ratio \(R = {\mit \Gamma }({\rm K}^0_{\rm L} \to (\pi \mu )_{\rm atom}\nu )/ {\mit \Gamma }({\rm K}^0_{\rm L} \to \pi \mu \nu )\) is calculated as a function of \(\xi = f_-/f_+\), where \(f_{\pm }\) are dimensionless forip factors for the K\(^0_{\rm L}\). The world average values \(\xi = -0.2(-0.9)\) from K\(_{\mu 3}\)/K\(_{e 3}\) (muon polarization) measurements give \(R = 3.8 (2.7) \times 10^{-7}\). Bethe’s theory of inelastic collisions is adapted to the calculation of the ionization cross-section \(\sigma _{\rm ion}\) for a relativistic (\(\pi \mu )_{\rm atom}\) in the 1\(S\) state due to its interaction with the screened Coulomb field of a target (foil) atom. In particular, for a (\(\pi \mu )_{\rm atom}\) with an energy of 10\((m_{\pi }+m_{\mu })c^2\) incident on an aluminum target (foil) atom, \(\sigma _{\rm ion} = 7.4 \times 10^{-22}\) cm\(^2\). These calculations are relevant to the experiments being currently performed by M. Schwartz and collaborators at Brookhaven and FNAL.

abstract

The model for the (p, \(\alpha \)) reaction on heavy nuclei is developed. Starting from the three-body approach to the (p, \(\alpha \)) reaction and the quasi-particle-phonon model for heavy deformed nuclei, the cross sections for the (p, \(\alpha \)) reactions on \(^{162}\)Dy, \(^{166,168}\)Er and \(^{176,178,180}\)Hf targets are calculated.

abstract

The shell model calculations with MSDI for \(^{42}\)Ca and \(^{42}\)Sc nuclei are extended by including the 1g\(_{9/2}\) orbit. The adjustable parameters \(A_{\rm T}\) are treated either as state independent or as state dependent. Inclusion of the 1g\({9/2}\) orbit produces no substantial changes in the density and the sequence of the states.

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The problem of the electromagnetic and thermodynamic arrow of time is discussed within the framework of the imperfect fluid Friedman cosmology.

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The evolution equations derived for parton distributions by Altarelli and Parisi are reformulated so, as to include explicit loss terms. This gives equations closer to master equations from statistical physics and supplies the necessary regularization of divergences without involving arguments foreign to the parton model. Relations with other approaches are also discussed.