As a possible method to decrease CTE losses, the ACS/WFC post- ash capabilities have been tested and a reference le has been created. The ash level is highly varied across both WFC CCDs, with a factor of two di erence in signal level between the brightest and the darkest parts of the ash. The direction of the variation is such that the post- ash is brightest far from the readout ampliers, where the CTE trailing is stronger. The added noise and uneven correction of the post- ash, along with the success of the pixel-based and photometric CTE corrections already in place, result in a limited set of cases where post- ash may be helpful.
Instrument Science Report ACS 2014-01
- Pub Date:
- April 2014
- Hubble Space Telescope;
- Space Telescope Science Institute;
- Advanced Camera for Surveys;