Data for: Background and Lunar Neutron Populations Detected by LEND and Average Concentration of Near-Surface Hydrogen Near the Moon’s Poles

This file tabulates neutron leakage flux measurements for data collected by the Lunar Reconnaissance Orbiter (LRO) Lunar Exploration Neutron Detector (LEND) instrument, organized by central latitude and longitude of 3°X3° pixels in cylindrical projection. Data were collected from 15 September 2009 through 31 December 2011. The measurements are reported in a simple ASCII text file. The three LEND detectors reported here are STN3 (Sensor for Thermal Neutrons), SETN (Sensor for Epi-Thermal Neutrons), and CSETN (Collimated Sensor for Epi-Thermal Neutrons). The columns are as follows:
LODX = longitude index
LADX = latitude index
E_long = east longitude at pixel center
W_long = west longitude at pixel center
lat = latitude
STN3 cts = # neutron detections, including corrections for detector sensitivity variation and cosmic ray flux variation
STN3 bkd = estimated # neutron detections due to background in detector
STN3 sec = total integration time, in seconds
SETN cts = # neutron detections, including corrections for detector sensitivity variation and cosmic ray flux variation
SETN bkd = estimated # neutron detections due to background in detector
SETN sec = total integration time, in seconds
CSETNcts = # neutron detections, including corrections for detector sensitivity variation and cosmic ray flux variation
CSETNbkd = estimated # neutron detections due to background in detector
CSETNsec = total integration time, in seconds, summed over all operating CSETN detector elements
alt km = average altitude above lunar surface (selenoid), in km, within this pixel element.

Net flux is number of detections minus background, divided by integration time. For CSETN, this will result in flux/detector; multiply by 4 to standardize by LEND reporting for four operational CSETN detector elements.

"Background" is actual spacecraft background plus out-of-band neutron flux. For STN3, out of band flux includes epithermal neutrons, derived from SETN detector. For SETN, out of band flux includes thermal neutrons derived from STN3 detector (minimal contribution). For CSETN, only background is subtracted, no out of band contribution.