WFC3/UVIS Eper CTE 2009-2020
Abstract
This report examines the changes in Charge Transfer Efficiency (CTE) as computed by the Extended Pixel Edge Response (EPER) technique. The data for the study were acquired from Cycle 17 through Cycle 26 (August 2009-present). Over the last 10 years, the CTE has declined below 0.9990 for the lowest signal level (~160 e-). In our analysis and report from 2016 we determined that the rate of decline is no longer well-matched by a linear fit but by a quadratic function instead. In 2016 we noted that this may indicate that the CTE decline is leveling off or reducing with time. Given the 10 years of data collected, we observe the periodic nature of the linear fit residuals and find that it is anti-correlated to solar activity. This is the first time this effect has been observed in practice in the WFC3 EPER data.
- Publication:
-
Space Telescope WFC Instrument Science Report
- Pub Date:
- May 2020
- Bibcode:
- 2020wfc..rept....6K
- Keywords:
-
- HST;
- Hubble Space Telescope;
- Space Telescope Science Institute;
- STScI;
- WFC3;
- Wide Field Camera 3;
- UVIS;
- EPER;
- CTE;
- SAA