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Innovative scintillation detector based on cerium bromide crystal was developed and manufactured. Laboratory measurements of detectors background for cerium bromide and lanthanum bromide were performed and demonstrated that cerium bromide crystals are preferable for spectroscopy investigations of potassium or other celestial body soil elements’ gamma lines. Experimental test bench for nuclear planetology (ETB-NP) for laboratory investigations with use of active methods of pulse neutron probing of celestial bodies’ soil test samples was created. Experimental studies provided data on background estimations certainty in nuclear physics measurements for tests and calibrations of instruments in laboratory environment. First series of tests with first soil samples series consisting of glass prism target containing layers of polyethylene at different depths were conducted. Die-away curves profiles studies of epithermal and thermal neutrons after pulse neutron radiation of prism target showed that secondary neutrons flux depends on the depth of polyethylene layer location within the prism target. First issues of software for Planetary Soils Contents Analysis (PSCA) were created. Numerical modelling of nuclear physics processes during DAN PNG pulse neutron generator interaction with prism target containing polyethylene layers at different depths was performed. It shows good agreement between numerical modeling of after-pulse neutron die-away radiance from prism target and laboratory measurements. First issue of PSCA-LEND software was used for numerical modeling of generation, transfer within the soil and registration within the detectors of Lunar natural neutron emission under the influence of galactic cosmic rays. Results from this modeling were compared to actual measurements of LEND neutron telescope on the lunar orbit provided for neutron flux estimations at different phases of solar activity. It was demonstrated, that variable neutron flux from the lunar surface agrees well with variations of neutron component of radiation environment onboard the International Space Station on the Earth’s orbit, as well as with neutron flux from Martian surface. Water content in some areas at Lunar poles was estimated to be as high as 0.4% mass, and these areas do not necessarily coincide with “cold traps” at the bottoms of polar craters where solar rays never reach. Comparison of neutron measurements and lunar relief showed that water ice concentration is higher on the slopes facing ploewards (to the north in the northern pole areas and to the south in the southern pole areas). First issue of PSCA-DAN software was used for numerical modeling of generation, transfer within the soil and registration within the detectors of secondary neutron emission from martian soil after high energy neutron pulses generated by the neutron generator part of the DAN instrument. Comparison of experimental measurements by DAN instrument with numerical modeling results showed that the best agreement is provided by two-layer water content model and one-layer chlorine content model. Parameters of this model, showing the best accordance with measurements, can be used for experimental assessment of water content in the upper level, depth of the lower layer, water content in the lower layer and average chlorine concentration. |