3.1.3 Reading the SXT Effective Area File
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Although it is not normally necessary to access the effective are data file directly, it is
very easy to do so. In IDL you must type:
IDL> file = CONCAT_DIR('$DIR_SXT_SENSITIVE','sra930211_01.genx')
IDL> restgen,file=file, str=area
IDL> help,area,/str
** Structure MS_125793397004, 5 tags, length=11600:
WAVE FLOAT Array(290)
ENTRANCE FLOAT Array(290)
CCD FLOAT Array(290)
MIRROR FLOAT Array(290)
FILTER FLOAT Array(6, 290)
IDL> plot_oi,area.wave,area.entrance,xr=[1,100]
IDL> plot_oo,area.wave,area.filter(0,*),xr=[1,100],yr=[.001,1]
The last two plot commands will reproduce Fig. 2 (a) and the first panel
in Fig. 3, respectively. In the data structure, WAVE is a vector of
wavelengths, ENTRANCE is the double entrance filter transmission,
CCD is the CCD QE, MIRROR is the mirror effective area (including
obscuration), and FILTER is the effective area through the various
filters. The order of the filter data is according to filter thickness going
from 0=open to 5=Be119. Note: this is not the normal SXT filter numbering scheme.
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