The report outlines the cycle of work carried out in the JINR Laboratory of Radiation Biology. Research areas: assessment of radiation risk for astronauts during long-term interplanetary flights and development of methods of experimental space radiobiology using computer modelling.

The existing models of galactic cosmic ray (GCR) spectra are under discussion. The model of the German Aerospace Center was implemented in GCRs Spectra software for further computer modelling. A computer model of a spacecraft was developed, and detailed calculations of the particle spectra of the mixed internal radiation field were performed. The simulation of interaction of the GCR particles with the spacecraft model was performed by the Monte Carlo FLUKA programme. Verification of the obtained results was carried out using measurement data of the RAD and Liulin-MO detectors. A new approach was used to assess radiation risk based on an effective dose for group of never-smoking men which is a more consistent assessment that takes into consideration the radioresistance of astronauts.

The existing approaches to modelling of the mixed radiation field using accelerators of heavy charged particles are being considered. A new approach to modelling of the space radiation environment within the framework of the programme of applied innovative research at the JINR NICA complex is being proposed. A mathematical model of the GCR simulator has been developed, the model is implemented in gcrs software. The initial data necessary for the development of the GCR simulator model has been obtained using FLUKA and PHITS programmes.