[en] A number of lines of investigation into the structure of the nucleon have converged to the point where we believe that one has a consistent explanation of the well known proton spin crisis

[en] A new method is proposed to investigate the internal geometrical structure of an extended particle surrounded by an incomplete virtual dressing field. This method involves analysing the time-dependent virtual field at large distances from the particle, without any direct interaction with the latter. As an example, the pulselike, time-dependent virtual field of an extended QED source is investigated using a model which has a well-known counterpart in meson theory. In the framework of nonrelativistic QED it is shown that, contrary to the case of a point source, the pulse has finite width and height. For the case of a spherically symmetric source, it is explicitly shown that the width and shape of the pulse at distance r from the particle depend on the parameters determining the space structure of the source. It is concluded that the study of the field of half-dressed particles may provide a new method to investigate their internal structure

[en] We retrace the discovery of the muon and stress its importance in the establishment of the standard model in particle physics. We remark the necessity of the existence of three families. At the end we speculate on some recent issues. (Author) 12 refs

[en] The effects of movement of the side walls of a confined granular packing are studied by discrete element, molecular dynamics simulations. The dynamical evolution of the stress is studied as a function of wall movement both in the direction of gravity as well as opposite to it. For all wall velocities explored, the stress in the final state of the system after wall movement is fundamentally different from the original state obtained by pouring particles into the container and letting them settle under the influence of gravity. The original packing possesses a hydrostaticlike region at the top of the container which crosses over to a depth-independent stress. As the walls are moved in the direction opposite to gravity, the saturation stress first reaches a minimum value independent of the wall velocity, then increases to a steady-state value dependent on the wall velocity. After wall movement ceases and the packing reaches equilibrium, the stress profile fits the classic Janssen form for high wall velocities, while some deviations remain for low wall velocities. The wall movement greatly increases the number of particle-wall and particle-particle forces at the Coulomb criterion. Varying the wall velocity has only small effects on the particle structure of the final packing so long as the walls travel a similar distance.

No abstract available

[en] The systematic classification of elementary particles is discussed and the theory of their structure is described. (M.D.)

[en] Recent progress in translating the increased precision and volume of deep inelastic data and information from hadronic collisions into parton distribution functions (PDFs) is reviewed. We discuss how small-x structure function (SF) data may be able to shed light on which large logarithms are relevant. (author)

[en] This Corrigendum contains a text that should replace the text between equations (16) and (19) (including equations (19)) in the article 'The Gerasimov-Drell-Hearn sum rule and nucleon structure', published in J. Phys. G: Nucl. Part. Phys. v. 22 p. 293-303

[en] We investigate in the proton form factor the possibility to have a zero in the space-like region. As a consequence the e-p differential cross-section would have a dip and a second maximum which are accessible to experiment. If the existence of such structure would be revealed it would be very important for understanding the composite nature of the proton

[en] The possible structure of charged leptons is discussed. A classical model is developed of a charged particle interacting locally with the external electromagnetic field, having at the same time a finite electromagnetic self-mass. It is shown that the spin, trembling motion and rest mass may be considered to be indicative of the three-centre structure of the charged particle. (Z.J.)