28 September 2000
In updating the ACIS QE files, an error was found in the -S data: the
-I UV blocking filter was used instead of the -S (thinner aluminum).
A plot near the end of this document shows the size of the error.
1 September 2000
I have updated the ACIS QE tables, primarily used by mkarf, mkgarf, mkinstmap, with the more finely gridded data (0.2eV) now available from the Calibration group. This is especially important for grating observations.
(Note: These files do NOT incorporate CTI degradation affects. That is handled by the QE Uniformity Map.)
ARDlib (Analysis Reference Data library) provides the primary interface to this file via the CIAO response tools. (See ardlib.par.)
New file:
acisD1997-04-17qeN0003.fits.gz
Previous: acisD1997-04-17qeN0002.fits.gz
This is the silicon edge region, which has been particularly troublesome for HETGS spectroscopy, since the Si XIII (He-like) forbidden line is at 6.74A (1.84 keV), and because spurious features are generated in flux-calibration of sources with a strong continuum.
This is the blocking filter aluminum edge feature. There is little change in the structure, but the depth of the Front-Illuminated CCD is reduced.
This is the oxygen edge region:
i0_w203c4r_eff_0700_release.qdp
i1_w193c2_eff_0700_release.qdp
i2_w158c4r_eff_0700_release.qdp
i3_w215c2r_eff_0700_release.qdp
s0_w168c4r_eff_0700_release.qdp
s1_w140c4r_eff_0700_release.qdp
s2_w182c4r_eff_0700_release.qdp
s3_w134c4r_eff_0700_release.qdp
s4_w457c4_eff_0700_release.qdp
s5_w201c3r_eff_0700_release.qdp
and filter transmissivities:
acis_i_xray_trans_1198.qdp
acis_s_xray_trans_1198.qdp
The union of the grids was formed; QE and transmissivity were interpolated
to that grid and multiplied together. "Pruning" was done to reduce
the grid to the number of points sufficient for 0.1% accuracy under linear
interpolation (2000 points out of 65000).
--------------------------------------------------------------------------------
Dataset: acisD1997-04-17qeN0003.fits.gz
--------------------------------------------------------------------------------
Block Name
Type Dimensions
--------------------------------------------------------------------------------
Block
1: PRIMARY
Null
Block
2: AXAF_QE1
Table 3 cols x 1972
rows
Block
3: AXAF_QE2
Table 3 cols x 1959
rows
Block
4: AXAF_QE3
Table 3 cols x 1941
rows
Block
5: AXAF_QE4
Table 3 cols x 1964
rows
Block
6: AXAF_QE5
Table 3 cols x 1957
rows
Block
7: AXAF_QE6
Table 3 cols x 1340
rows
Block
8: AXAF_QE7
Table 3 cols x 1848
rows
Block
9: AXAF_QE8
Table 3 cols x 1320
rows
Block 10:
AXAF_QE9
Table 3 cols x 1938
rows
Block 11:
AXAF_QE10
Table 3 cols x 1971
rows
--------------------------------------------------------------------------------
Columns for Table Block
AXAF_QE1
--------------------------------------------------------------------------------
ColNo Name
Unit Type
Range
1
ENERGY
keV Real4
-Inf:+Inf
2
QE
Real4 0:1
3
SYS_MIN
Real4 -Inf:+Inf
Blocks 2-10 are for the ten chips of the -I and -S array. They
are nominally in sequential order by CCDID (but CCDID is a header keyword
so a serial block order is not required). Each block has the same
columns as block AXAF_QE1.
The file was created with acis_qbar_ard.pro
and subsidiary routines.
