The differences of the masses of isotopes with atomic numbers between ∼ 10 and ∼ 30 can be described within the chiral soliton model in satisfactory agreement with data. The rescaling of the model is necessary for this purpose -decrease of the Skyrme constant by ∼ 30%, providing the "nuclear variant" of the model. The asymmetric term in Weizsacker-Bethe-Bacher mass formula for nuclei can be obtained as the isospin dependent quantum correction to the nucleus energy. Some predictions of the binding energies of neutron rich isotopes are made in this way from, e.g. 16 Be, 19 B to 31 Ne or 32 Na. The neutron rich nuclides with high values of isospin are unstable relative to the decay due to strong interactions. The SK4 (Skyrme) variant of the model, as well as SK6 variant (sixth order term in chiral derivatives in the Lagrangian as solitons stabilizer) are considered, the rational map approximation is used to describe multiskyrmions. * 1) Probably, one of the first attempts to include the sixth order term was made in [7] where the bound B = 2 torus-like configuration was found, similar to the case of fourth order, or Skyrme term.

The energies of baryon states with positive strangeness, or anti-charm (-beauty) are estimated in chiral soliton approach, in the "rigid oscillator" version of the bound state soliton model proposed by Klebanov and Westerberg. Positive strangeness states can appear as relatively narrow nuclear levels (Θ-hypernuclei), the states with heavy anti-flavors can be bound with respect to strong interactions in the original Skyrme variant of the model (SK4 variant). The binding energies of anti-flavored states are estimated also in the variant of the model with 6-th order term in chiral derivatives in the lagrangian as solitons stabilizer (SK6 variant). The latter variant is less attractive, and nuclear states with anti-charm and anti-beauty can be unstable relative to strong interactions. The chances to get bound hypernuclei with heavy anti-flavors increase within "nuclear variant" of the model with rescaled model parameter (Skyrme constant e or e ′ decreased by ∼ 30%) which is expected to be valid for baryon numbers greater than B ∼ 10. The rational map approximation is used to describe multiskyrmions with baryon number up to ∼ 30 and to calculate the quantities necessary for their quantization (moments of inertia, sigma-term, etc.).

In memory of Karen Avetovich Ter-Martirosyan, the Teacher. IntroductionDescription of hadrons structure in terms of their quark constituents is generally accepted, but the alternative description within e.g. topological soliton (Skyrme) model [1,2] and its modifications also is useful and has certain advantages in comparison with traditional approaches. The chiral (topological) soliton approach is based on general principles and few ingredients incorporated in the effective chiral lagrangian, this is the reason for apparent simplifications in comparison, for example, with attempts to solve relativistic many-body problem. To simplify the latter, some additional objects like diquarks and triquarks have been phenomenologically introduced and discussed especially intensively after recent observations of the so called pentaquarks [3,4] 1 . Concept of diquarks "as an organizing principle for hadron spectroscopy" is considered in details in [12], see also [13]. The concepts of diquarks, triquarks or other correlated quark clusters are certainly of useful heuristic value, although their properties have not been deduced rigorously from basic QCD lagrangian. It should be noted that diquarks present in different physical states, baryons or mesons, can have different properties like the effective mass and size, even for same quantum numbers. 2In the present paper we perform explicit calculation of the strangeness contents of exotic and nonexotic baryon states at arbitrary number of colors N c , and discuss connection of the chiral soliton approach (CSA) and simple quark (pentaquark) model for exotic baryon states, 1 A contradictive present situation with experimental observation of possible pentaquark states is discussed, e.g. in [5,6]. Consideration of baryon states in the present paper is relevant independently on particular values of masses, widths and other properties of exotic baryon states measured experimentally. A detailed discussion of theoretical predictions of these states can be found in [7,8,9,10,11] 2 Some analogy with nuclei can be noted: two-, three-, etc. nucleon clusters play an important role in the structure of heavy nuclei, however, it is not possible to evaluate their properties from those of deuteron, helium etc., only. See, e.g. [14] for discussion of the role of femtometer toroidal structures in nuclei.

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