A quantitative comparison of lunar orbital neutron data

TL;DR

This paper quantitatively analyzes lunar neutron data from LEND CSETN, revealing that most detected neutrons originate from high energy epithermal neutrons, and discusses implications for lunar water distribution.

Contribution

It provides a quantitative assessment of the background in LEND CSETN data and compares its spatial resolution to Lunar Prospector, enhancing lunar water detection methods.

Findings

At least 90% of LEND CSETN flux is from high energy epithermal neutrons.

LEND CSETN's effective resolution is comparable to Lunar Prospector.

The neutron map can help probe lunar water distribution.

Abstract

Data from the Lunar Exploration Neutron Detector (LEND) Collimated Sensors for Epithermal Neutrons (CSETN) are used in conjunction with a model based on results from the Lunar Prospector mission to quantify the extent of the background in the LEND CSETN. A simple likelihood analysis implies that at least 90% of the lunar component of the LEND CSETN flux results from high energy epithermal neutrons passing through the walls of the collimator. Thus, the effective full-width at half-maximum of the LEND CSETN is comparable with that of the omni-directional Lunar Prospector Neutron Spectrometer. The resulting map of high energy epithermal neutrons offers the opportunity to probe the hydrogen abundance at low latitudes, and provide constraints on the distribution of lunar water.