Comparison Between MIT and XRCF (Phase I) Measurements of Relative Quantum Efficiency

To compare measurements of relative quantum efficiency made at MIT's Center for Space Research (CSR) and Marshall Spaceflight Center's X-ray Calibration Facility (XRCF), we have used the data in Table 4.54 to compute relative QE ratios referenced to device S2. The results are presented in Table 4.58. Similarly, we have compiled relative QE ratios referenced to S2 from telemetry data taken at XRCF (see Table 4.59). The telemetry data was taken using windows near the top and bottom of each device to avoid saturating the telemetry stream. The pileup correction factors applied to the XRCF count rates are presented in Table 4.60.
 
 

Table 4.58: Spatially Averaged Relative Detection Efficiency at CSR--Referenced to S2. In each box the mean is given as the top entry; the RMS variation is given in parentheses below it.

 

Flight	Position	Mean (RMS) Relative Efficiency vs. Energy (keV)
Device		0.525	0.677	1.740	2.015	4.509	5.894	8.040
		O	F	Si	P	Ti	Fe55	Cu
w203c4r	I0	0.858	0.790	0.979	0.930	0.990	0.970	0.898
		(0.055)	(0.049)	(0.071)	(0.066)	(0.072)	(0.074)	(0.090)
w193c2	I1	0.878	0.798	0.977	0.949	0.991	0.969	0.907
		(0.058)	(0.053)	(0.073)	(0.069)	(0.075)	(0.077)	(0.087)
w158c4r	I2	0.906	0.836	0.983	0.966	0.993	0.965	0.906
		(0.055)	(0.051)	(0.070)	(0.067)	(0.071)	(0.073)	(0.084)
w215c2r	I3	0.882	0.809	0.980	0.936	0.991	0.972	0.894
		(0.056)	(0.049)	(0.074)	(0.069)	(0.076)	(0.079)	(0.092)
w168c4r	S0	0.939	0.868	0.987	0.960	0.992	0.965	0.881
		(0.058)	(0.053)	(0.074)	(0.070)	(0.074)	(0.076)	(0.091)
w182c4r	S2	1.000	1.000	1.000	1.000	1.000	1.000	1.000
		(0.000)	(0.000)	(0.000)	(0.000)	(0.000)	(0.000)	(0.000)
w457c4	S4	0.901	0.853	0.988	0.966	0.995	0.991	0.963
		(0.051)	(0.052)	(0.063)	(0.060)	(0.064)	(0.068)	(0.091)
w201c3r	S5	0.886	0.817	0.984	0.939	0.996	0.992	0.967
		(0.051)	(0.047)	(0.067)	(0.061)	(0.068)	(0.072)	(0.095)
w140c4r	S1	3.078	2.606	1.033	1.439	0.921	0.715	0.522
		(0.207)	(0.159)	(0.074)	(0.110)	(0.093)	(0.066)	(0.053)
w134c4r	S3	2.989	2.417	1.082	1.489	1.004	0.835	0.640
		(0.170)	(0.187)	(0.084)	(0.116)	(0.082)	(0.072)	(0.068)

Table 4.59: Spatially Averaged Relative Detection Efficiency from XRCF Telemetry--Referenced to S2

 

Flight	Position	Mean Relative Efficiency vs. Energy (keV)
Device		0.277	0.525	0.705	1.487	1.740	2.166	4.509	6.399	8.040
		C	O	Fe L	Al	Si	Nb L	Ti	Fe K	Cu
w203c4r	I0		0.842	0.810	0.962	0.982	0.942	0.981	0.948	0.903
w193c2	I1		0.868	0.805	0.965	0.979	0.954	0.985	0.946	0.910
w158c4r	I2		0.909	0.849	0.979	0.996	0.969	0.988	0.951	0.894
w215c2r	I3		0.865	0.807	0.976	0.994	0.961	0.989		0.907
w168c4r	S0	0.687	0.912	0.873	0.979	0.986	0.964	1.002	0.953	0.904
w182c4r	S2	1.000	1.000	1.000	1.000	1.000	1.000	1.000	1.000	1.000
w457c4	S4	0.625	0.897	0.910	0.975	0.991	0.965	1.005	0.980	$1.049^\ast$
w201c3r	S5	0.625	0.876	0.828	0.966	0.983	0.966	0.999	0.972	1.008
w140c4r	S1	36.619	3.460	3.022	1.071	1.034	1.287	0.847	0.617	0.527
w134c4r	S3	35.679	3.280	3.033	1.115	1.092	1.342	0.949	0.755	0.671
$^{\ast}$ The XRCF bias for this data point is peculiar.

 

Table 4.60: Pileup Correction Factors Applied to Count Rates from XRCF Telemetry

 

Flight	Position	Pileup Correction vs. Energy (keV)
Device		0.277	0.525	0.705	1.487	1.740	2.166	4.509	6.399	8.040
		C	O	Fe L	Al	Si	Nb L	Ti	Fe K	Cu
w203c4r	I0		1.001	1.007	1.049	1.007	1.020	1.017	1.021	1.119
w193c2	I1		1.001	1.007	1.049	1.007	1.020	1.017	1.021	1.117
w158c4r	I2		1.001	1.007	1.050	1.008	1.021	1.009	1.015	1.116
w215c2r	I3		1.001	1.007	1.050	1.008	1.021	1.017		1.116
w168c4r	S0	1.000	1.001	1.002	1.050	1.008	1.021	1.018	1.028	1.139
w182c4r	S2	1.000	1.001	1.007	1.051	1.008	1.022	1.013	1.020	1.140
w457c4	S4	1.000	1.001	1.003	1.050	1.008	1.021	1.011	1.029	1.164
w201c3r	S5	1.000	1.001	1.002	1.049	1.008	1.021	1.018	1.029	1.157
w140c4r	S1	1.001	1.004	1.007	1.044	1.007	1.029	1.019	1.016	1.036
w134c4r	S3	1.001	1.003	1.009	1.046	1.008	1.030	1.016	1.018	1.042