XMM-Newton Data Files Handbook

4.1.9.2 ERM Spectra Files

ERM Spectra files (*RM*ESX.FIT) are produced to cover every observation and slew period. They contain the spectra created in the ERM. The ERMS data consist of three measurements per readout, two spectra from the High Energy Detectors (HEDs) and one from the Low Energy Detector (LED). 256 spectral bins are available in the LED and HED. The HEDs are sensitive to electrons above 200 keV and protons above 10 MeV, while the LED is sensitive to electrons with energies above 50 keV. The two high energy spectra are the ``HE detector spectrum'' (HES), with events from either one or both HE detectors, and the ``coincidence HE spectrum'' (HEC), in which only events detected by both HEDs will be recorded. Each entry (frame) corresponds to a complete spectrum. The spectra are accumulated every 2 telemetry packets, if the ERM is operated in fast mode and every 128 telemetry packets if the ERM is operated in slow mode. Each ERM file consists of a single binary table, whose columns are specified in Table 24.

Table 24: ERM Spectra files (*RM*ESX.FIT) binary table columns

Name	Type	Units	Description
FTCOARSE	1J	SECONDS	Coarse frame time
FTFINE	1I		Fine frame time
FRAME	1J	COUNTER	Frame identifier
SPLE	256I	COUNTS	SP_LE Accumulated spectrum$^a$
SPHES	256I	COUNTS	SP_HES Accumulated spectrum$^a$
SPHEC	256I	COUNTS	SP_HEC Accumulated spectrum$^a$

$^a$See Sect. 4.1.9.2 for definition