WFC3/UVIS: External CTE Monitoring 2009-2024
Benjamin Kuhn
TL;DR
This study analyzes 14 years of Hubble WFC3/UVIS data to quantify charge transfer efficiency flux losses, update correction models, and provide recommendations to mitigate these effects in astronomical observations.
Contribution
It offers the first long-term analysis of CTE flux losses for WFC3/UVIS and updates empirical correction coefficients based on extensive data from 2009 to 2024.
Findings
CTE flux loss rate for faint sources is about 0.05 mag per 2051 pixels per year.
Minimum background level of 20-25 e$^-$ per pixel reduces flux loss significantly.
2024 data shows flux losses of up to 23% for faint sources and over-corrections for bright sources at high backgrounds.
Abstract
This report examines Charge Transfer Efficiency (CTE) flux losses in the Wide Field Camera 3 UVIS detector aboard the Hubble Space Telescope. Spanning approximately 14 years of observations from October 2009 to February 2024, the study analyzes CTE flux loss trends across various total background levels and source fluxes. In addition to analyzing the present state of CTE flux losses, we provide updated coefficients for the empirical model for point source photometry corrections in both non-CTE-corrected (FLT) and CTE-corrected (FLC) data. Between 2009 and 2023, the rate of CTE flux loss for a 500-2000 e source, farthest from the readout, in FLT data with a 1-3 e/pix background, is measured to be 0.05 mag/2051 pix/year. The recommended minimum total background level to mitigate CTE losses remains at 20-25 e/pix. At that level, we find that 500-2000 e…
Peer Reviews
No public reviews on file for this paper yet. If you reviewed it on a platform where reviews are public (OpenReview, ICLR, NeurIPS, ICML), you can paste yours below so the community can read it here.
Videos
No videos yet. Explain this paper in a talk, walkthrough, or lecture? Add one.
Taxonomy
TopicsCCD and CMOS Imaging Sensors · Calibration and Measurement Techniques · Photocathodes and Microchannel Plates