HR: 1340h
AN: MR23A-1029 [Abstracts]
TI: Simulation of Water Detection in Lunar Polar Regions With Different Types of Neutron Detectors
AU: * Zatsepin, O V
EM: zatsepin@umd.edu
AF: University of Maryland, Department of Physics, College Park, MD 20742, United States
AU: Sagdeev, R Z
AF: University of Maryland, Department of Physics, College Park, MD 20742, United States
AU: Sanin, A B
AF: Institute for Space Research, 84/32 Profsoyuznaya Str., Moscow, 117997, Russian
Federation
AU: Milikh, G M
AF: University of Maryland, Department of Physics, College Park, MD 20742, United States
AB:
Permanently shadowed craters in the polar regions of the Moon can probably contain water ice. It is possible to
search for ice deposits by measuring variations of lunar neutron albedo caused by the permanent bombardment
of the Moon by Galactic Cosmic Rays. Different types of neutron detectors can be used to measure variations of
the neutron albedo.
We consider a set of models of neutron detectors with equal mass. All instruments use 3He proportional
counters that are designed to detect variations of epithermal neutron flux. A lunar map of hydrogen distribution
could be developed by analyzing those variations. If the lunar polar regions contain water ice deposits then
hydrogen abundance in lunar soil in those regions increases, and thus such spots can be detected. For the
purpose of achieving better spatial resolution some instruments use collimators. Our models which have
detailed 3D-geometry are intended for the Monte-Carlo simulation with MCNPX code.
Besides, we consider a set of lunar soil models in our simulations. For each of these models we calculate the
neutron background flux. A special procedure was developed for simulations of neutron flux detected by different
instruments. Different lunar soil models were produced by varying such parameters as density, water abundance,
temperature and geometry of possible region containing water ice. As a result for each type of detector we
obtained data on variation of counting rate corresponding to variation of lunar soil models. These models will be
eventually tested against observations of the future lunar missions.
DE: 0798 Modeling
SC: Mineral and Rock Physics [MR]
MN: 2007 Fall Meeting