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For a long time it was known that deuteron, as a weakly coupled nucleon pair, has no excited states. However, A.M. Baldin et al, commenting results of the first physical experiment with accelerated nuclei at JINR synchrophasotron, assumed as far back as in 1979 that one of peaks in a differential cross-section may arise due to an "excited state of deuterium". We have established that one of the peaks in the cross-section may be explained indeed in this way and corresponds to the dibaryon reported by WASA-at-COSY Collaboration. Another peak in the same region is interpreted most likely by interference of several N * -resonances, and this possibility was also mentioned in the paper by A.M. Baldin et al. Further experimental studies based on modern experimental facilities and more abundant statistics are necessary to verify these observations.

A model of a multilayer device with non-trivial geometrical structure and nonlinear dependencies of thermodynamic material properties at cryogenic temperatures is suggested. A considered device, called cryogenic cell, is intended for use in multicharged ion sources for pulse injection of gaseous species into ionization space of ion sources. The main requirement for the cryogenic cell operation is the permanent opening and closing for gaseous species injection in a millisecond range, while cell closing is provided by freezing of the gaseous specie at the outer surface of the cell and the cell opening -by the corresponding pulse heating of the cell surface up to definite temperature. The thermal behaviour of the device in a millisecond time range is simulated. The algorithm for solving the non-stationary heat conduction problem with a time-dependent periodical heating source is suggested. The algorithm is based on finite difference explicit-implicit method. The OpenCL realization of the algorithm is discussed. The optimal particular choice of the parameters to provide the required pulse temperature regime of the designed cryogenic cell for the chosen working gas is presented. Based on these results further optimization can be formulated.

Density fluctuations of intranuclear matter suffering collisions with projectile particles are capable to turn into multiquark clusters with chiral symmetry restored.Theoretical analysis of these processes requires an additional taking account of finite size effects in the region of the chiral phase transition. From the experimental point of view, this method of observation of the chiral phase transition has its inherent advantages due to a relatively moderate number of secondary particles to be registered.