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Hubble Space Telescope
Post-SM4 Internal CTE for WFC

WFC Serial FPR

FPR serial CTE is similar to EPER, i.e., insignificant compared to EPER parallel CTE and showing chip dependence. However, unlike EPER serial CTE, discontinuity around the time of -77C to -81C temperature change is more apparent.

ACS ISR 2005-03 did not publish coefficients for FPR serial CTE. Below is the table with the new coefficients. MJD limits are defined such that MJD1 <= MJD < MJD2. Only Amps A and D ~1620e data are sufficient for fitting, so p coefficient could not be calculated (assumed to be 0). As a result, there are no predictions for CTE vs Signal. Their fits are shown in CTE vs Time.

MJD1 MJD2 AMP n c Notes about MJD2
52335 53918 Aa 3.683x10-6 6.890x10-9 -77C to -81C; Switched to Side-2
Db 1.132x10-6 3.848x10-9
53918 58849 Aa 1.521x10-6 5.586x10-9 A distant future
Db -4.769x10-6 5.767x10-9
a WFC1. Only 1620e used.
b WFC2. Only 1620e used.

CTE vs Signal

Here is the legend:

CTE vs Time

Only Amps A and D ~1620e:

All data:

Here is the legend: