Fast resets of sub-windows on infrared detectors as a strategy for persistence mitigation

TL;DR

This paper investigates a rapid reset strategy for sub-windows on infrared detectors to reduce persistence artifacts, demonstrating potential benefits but also identifying possible issues with local reset level changes.

Contribution

It introduces a novel approach of continuously resetting small detector regions to mitigate persistence effects in infrared imaging.

Findings

Fast localized resets can reduce persistence artifacts.

Potential for persistent local reset level changes with intense illumination.

Strategy shows promise but requires further refinement.

Abstract

Persistence effects in HgCdTe infrared detectors cause significant artifacts that can impact the quality of science observations for up to many hours after exposure to bright/saturating sources. This problem will have a substantially greater impact on viable observing modes for infrared cameras on future ELTs due to the leap in sensitivities that is expected. In this paper we present new results from an updated test system that was previously used to prototype ``on-detector guide windows'' to provide fast T/T feedback to AO systems, interleaved with simultaneous (slow) full-frame readouts for science. We now explore the possibility of continuously resetting these small regions of the detector that are illuminated with a compact source as a strategy for mitigating persistence, using two different detectors. While our results generally show promise for this observing strategy, we found for one of our detectors that the combination of fast localized resets with intense illumination can introduce a potentially problematic persistent change in local reset levels.