Pileup Data

Last updated October 7, 1998
These tables contain pileup fractions for each test, calculated for all grades and for the standard grade set (02346). Click on each test ID to open the postscript file containing the spectrum for that test.

  • ``Photon'' pileup fractions are defined as the ratio of the sum of Photon in the n = 2-3 or n = 2-4 spectral pileup peaks to the total number of Photon in the main peak (n=1) + the pileup peaks, calculated as
    pp= sumn > 1 [An × n] / sumn >= 1 [An × n] ,

    where An is the area under the main peak or pileup peak.

  • ``Event'' pileup fractions are defined as the ratio of the total number of events in the pileup peaks to the total number of events in all peaks:
    pe = sumn > 1 [An] / sumn >=1 [An] .

    Test Photon Event
    All grades Std. grades All grades Std. grades
    On-axis PSF
    H-IAI-PI-1.021 0.098 0.085 0.051 0.044
    H-IAI-PI-2.019 0.099 0.093 0.052 0.049
    H-IAI-PI-3.001 0.576 0.445 0.340 0.240
    H-IAS-PI-1.041 0.057 0.043 0.029 0.022
    H-IAS-PI-12.002 0.093 0.072 0.049 0.037
    H-IAI-PI-2.022 0.158 0.140 0.082 0.072
    H-IAS-PI-2.043 0.100 0.079 0.052 0.041
    H-IAS-PI-2.044 0.158 0.129 0.082 0.066
    Count rate linearity tests
    H-IAI-CR-1.001 0.0800.071 0.041 0.037
    H-IAI-CR-1.003 0.2450.230 0.132 0.124
    H-IAI-CR-1.005 0.5340.469 0.313 0.264
    H-IAI-CR-1.007 0.5890.438 0.344 0.232
    H-IAI-CR-1.009 0.1250.104 0.067 0.055
    H-IAI-CR-1.011 0.2660.243 0.143 0.130
    H-IAS-CR-1.002 0.0640.051 0.033 0.026
    H-IAS-CR-1.004 0.2310.186 0.123 0.098
    H-IAS-CR-1.006 0.5480.395 0.319 0.212
    H-IAS-CR-1.008 0.6260.369 0.372 0.182

    Off-axis PSF
    Test Photon Event HRMA Pitch & Yaw
    All grades Std. grades All grades Std. grades
    H-IAI-PI-2.001 0.3030.268 0.179 0.155 Pitch=1.2, Yaw=1.19,
    defocus=+0.001
    H-IAI-PI-3.006 0.3480.273 0.191 0.146 Pitch=-7.49, Yaw=0,
    defocus=+0.023
    H-IAI-PI-2.007 0.3050.263 0.180 0.151 Pitch=1.2, Yaw=0,
    defocus=+0
    H-IAI-PI-2.013 0.3040.258 0.179 0.148 Pitch=0, Yaw=1.19,
    defocus=+0
    H-IAI-PI-7.005 0.1860.158 0.103 0.086 Pitch=-7.5, Yaw=-7.5,
    defocus=+0

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