  The primary components of radiation in interplanetary space are galactic
cosmic rays (GCR) and solar cosmic radiation (SCR). GCR originates from outside
of our Solar System, while SCR consists of low energy solar wind particles that
flow constantly from the Sun and the highly energetic solar particle events
(SPEs) that originate from magnetically disturbed regions of the Sun, which
sporadically emit bursts of energetic charged particles. Exposure to space
radiation may place astronauts and aviation crews at significant risk for
numerous biological effects resulting from exposure to radiation from a major
SPE or combined SPE and GCR. Doses absorbed by tissues vary for different SPEs
and model systems have been developed to calculate the radiation doses that
could have been received by astronauts during previous SPEs. For this reason a
new application DYASTIMA-R which constitutes a successor of the Dynamic
Atmospheric Shower Tracking Interactive Model Application (DYASTIMA) is being
developed. This new simulation tool will be used for the calculation of the
equivalent dose during flights scenario in the lower or higher atmosphere,
characterized by different altitudes, different geographic latitudes and
different solar and galactic cosmic ray intensity. Results for the calculated
energy deposition and equivalent dose are calculated during quiet and disturbed
periods of the solar cycles 23 and 24, are presented.
