Durham University

Department of Physics

Staff profile

Publication details for Prof Richard Massey

Massey, Richard (2010). Charge transfer inefficiency in the Hubble Space Telescope since Servicing Mission 4. Monthly Notices of the Royal Astronomical Society: Letters 409(1): L109-L113.

Author(s) from Durham

Abstract

We update a physically motivated model of radiation damage in the Hubble Space Telescope Advanced Camera for Surveys/Wide Field Channel, using data up to mid-2010. We find that charge transfer inefficiency increased dramatically before shuttle Servicing Mission 4, with ∼1.3 charge traps now present per pixel. During detector readout, charge traps spuriously drag electrons behind all astronomical sources, degrading image quality in a way that affects object photometry, astrometry and morphology. Our detector readout model is robust to changes in operating temperature and background level, and can be used to iteratively remove the trailing by pushing electrons back to where they belong. The result is data taken in mid-2010 that recovers the quality of imaging obtained within the first six months of orbital operations.