Downtime expected shortly as all LEDAS services are moved to a new server.
Background subtraction using many non-local off-source observations
The procedure to generate an universal background model is
identical to that in section 3.2,
except for the following points:
A large number, typically more than 10, off-source
observations are required: there must be sufficient observations to
adequately sample the 37-day cycle. The observations can be spread
over several months, but the best results will be obtained if some are
before the source observation and some are after.
The time counters, describing the induced radiation, should
be inserted into both the source and all the off-source data cubes
using the program bgdsaa37. The program bgdsaa37 differs
from bgdsaa as the decay parameters it creates vary on the
Checking the quality of the background fit by the methods
described in section 3.1 and 3.2 can be a prohibitively long and tedious
procedure because of the number of off-source data files
involved. Inspection of the CONSTANT parameter files
(bgd_constant00m.phad) can frequently help locate regions of poor
quality data as only small differences due to variations in the
diffuse cosmic X-ray background should be present.
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