The novel observation of an exotic strangeness S = +1 baryon state at 1.54 GeV will trigger an intensified search for this and other baryons with exotic quantum numbers. This state was predicted long ago in topological soliton models. We use this approach together with the new datum in order to investigate its implications for the baryon spectrum. In particular we estimate the positions of other pentaquark and septuquark states with exotic and with non-exotic quantum numbers.

The observation of neutrons turning into antineutrons would constitute a discovery of fundamental importance for particle physics and cosmology. Observing the n−n transition would show that baryon number (B) is violated by two units and that matter containing neutrons is unstable. It would provide a clue to how the matter in our universe might have evolved from the B = 0 early universe. If seen at rates observable in foreseeable next-generation experiments, it might well help us understand the observed baryon asymmetry of the universe. A demonstration of the violation of B − L by 2 units would have a profound impact on our understanding of phenomena beyond the Standard Model of particle physics.Slow neutrons have kinetic energies of a few meV. By exploiting new slow neutron sources and optics technology developed for materials research, an optimized search for oscillations using free neutrons from a slow neutron moderator could improve existing limits on the free oscillation probability by at least three orders of magnitude. Such an experiment would deliver a slow neutron beam through a magnetically-shielded vacuum chamber to a thin annihilation target surrounded by a low-background antineutron annihilation detector. Antineutron annihilation in a target downstream of a free neutron beam is such a spectacular experimental signature that an essentially background-free search is possible. An authentic positive signal can be extinguished by a very small change in the ambient magnetic field in such an experiment. It is also possible to improve the sensitivity of neutron oscillation searches in nuclei using large underground detectors built mainly to search for proton decay and detect neutrinos. This paper summarizes the relevant theoretical developments, outlines some ideas to improve experimental searches for free neutron oscillations, and suggests avenues both for theoretical investigation and for future improvement in the experimental sensitivity.

Analytical treatment of skyrmions given by rational map (RM ) ansaetze proposed recently for the Skyrme model is extended for the model including the 6-th order term in chiral field derivatives in the lagrangian and used for the calculations of different properties of multiskyrmions. At large baryon numbers the approximate solutions obtained are similar to the domain wall, or to spherical bubbles with energy and baryon number density concentrated at their boundary. Rigorous upper bound is obtained for the masses of RM multiskyrmions which is close to the known masses, especially at large B. For the 6-th order variant the lower bound for masses of RM skyrmions is obtained as well. The main properties of the bubbles of matter are obtained for arbitrary number of flavours. They are qualitatively the same for the 4-th and 6-th order terms present in the lagrangian, although differ in some details.

The characteristic predictions of chiral soliton models - the Skyrme model and its extentions - are discussed. The chiral soliton models prediction of dibaryon states with masses below NN-pion threshold is in qualitative agreement with recent evidence for the existence of narrow dibaryons in reactions of inelastic proton scattering on deuterons and two-photon radiation in proton-proton scattering. The connection between isovector magnetic momentum operator and mixed tensor of inertia of multiskyrmion, as well as between isoscalar magnetic momentum and orbital tensor of inertia valid for skyrmions with any B-numbers allows to estimate the electromagnetic decay widths of some states of interest. Another kind of predictions are multibaryons with nontrivial flavour - strangeness, charm or bottom, which can be found, in particular, in high energy heavy ions collisions. It is shown that the large B multiskyrmions given by rational map ansaetze can be described reasonably well within the domain wall approximation, or as spherical bubble with energy and baryon number density concentrated at its boundary. A simple formula is obtained describing the masses of known RM multiskyrmions with good accuracy.Comment: 18 pages, 1 figure; abstract of paper is available in Cosy News, 9, pp. 5-7, October 200

The binding energies of neutron rich strangeness S = −1 hypernuclei are estimated in the chiral soliton approach using the bound state rigid oscillator version of the SU (3) quantization model. Additional binding of strange hypernuclei in comparison with nonstrange neutron rich nuclei takes place at not large values of atomic (baryon) numbers, A = B ≤∼ 10. This effect becomes stronger with increasing isospin of nuclides, and for "nuclear variant" of the model with rescaled Skyrme constant e. Total binding energies of 8 Λ He and recently discovered 6 Λ H satisfactorily agree with experimental data. Hypernuclei 7 Λ H, 9 Λ He are predicted to be bound stronger in comparison with their nonstrange analogues 7 H, 9 He; hypernuclei 10 Λ Li, 11 Λ Li, 12 Λ Be, 13 Λ Be etc. are bound stronger in the nuclear variant of the model. 1