# Predictive model of persistence in H2RG detectors

## TL;DR

This paper presents a model for understanding and correcting image persistence in H2RG infrared detectors by characterizing traps and using a digital filter to simulate charge trapping and detrapping.

## Contribution

The authors developed a behavior model using a digital filter to simulate charge trapping, enabling near real-time correction of persistence effects in H2RG detectors.

## Key findings

- Characterized traps in H2RG detectors at different wavelengths
- Developed a digital filter-based model for trap behavior
- Enabled near real-time persistence correction

## Abstract

Infrared hybridized detectors are widely used in astronomy, and their performance can be degraded by image persistence. This results in remnant images that can persist in the detector for many hours, contaminating any subsequent low-background observations. A different but related problem is reciprocity failure whereby the detector is less sensitive to low flux observations. It is demonstrated that both of these problems can be explained by trapping and detrapping currents that move charge back and forward across the depletion region boundary of the photodiodes within each pixel. These traps have been characterized in one 2.5 $\mu$m and two 5.3 $\mu$m cutoff wavelength Teledyne H2RG detectors. We have developed a behaviour model of these traps using a 5-pole Infinite Impulse Response digital filter. This model allows the trapped charge in a detector to be constantly calculated for arbitrary exposure histories, providing a near real-time correction for image persistence.