LRO LEND Extended Derived LEND Counts Data Reduced Data Record

RDRDLX – Extended Derived LEND Counts Data Reduced Data Record

Instrument: Lunar Exploration Neutron Detector

PDS Data Set ID: LRO-L-LEND-4/5-V1.0

For more information about LEND RDR products, see the RDR Product SIS.

For more information about all LEND products, see the LEND Archive Volume SIS.

The Lunar Exploration Neutron Detector (LEND) Extended Derived LEND Counts Data Reduced Data Record (RDRDLX) data products contain a time-series of Neutron Detector science data that contains supplemental values useful for interpretation of Derived LEND Data (RDRDLD) data, including uncertainties for neutron counts on each detector.

No spacecraft background subtraction is made for this dataset. The time series measurements of each of the un-collimated LEND neutron signals are corrected for altitude.

Once the altitude correction has been made to the data, it is examined to determine if data collection occurred during a solar particle event (SPE). SPEs significantly influence the LEND detectors’ counting rates, often increasing the counting rates by several orders of magnitude. Any data collected during times of intense solar activity are flagged and excluded from further routine data processing.

The following circumstances lead to a value of -1 being assigned to the count rate in the corresponding derived record:

  • Measurements obtained with the nadir angle of the spacecraft greater than 1.9° are ignored.

  • Raw counts from each of the detectors are examined for ‘outlier’ values, which could be produced either due to some micro-discharge in the HV circuit of a counter, or due to some corruptions in the instrument memory. Measurements are defined as outlier events based upon a specific count threshold for each detector (11 cps for CSETN1-4; 30 cps for SETN; and 49 cps for STN1-3).

  • Single or multiple detectors do not have high voltage applied for a period of time.

Data is also corrected for instrument warm-up, separation of charged particles and neutrons, and variation of galactic cosmic rays.

The RDRDLX data product is a time-series collection of neutron count uncertainties derived from the 9 neutron detectors aboard the LEND instrument, as well as a calculated sum of neutron counts and uncertainty across the four collimated sensors of epithermal neutrons, CSETN1-4. The data product is structured as a single 12-column, time-ordered data file for each collection day.

LEND RDRDLX products have the following file names:

LEND_RDR_DLX_yyyymmdd.DAT (with detached PDS label)

where:

yyyymmdd = 8-digit date specifier

In ODE, RDRDLX products have the following product IDs:

LEND_RDR_DLX_YYYYMMDD_DAT