Transient particle effects on the ISOCAM instrument on-board the Infrared Space Observatory

Gee

et al. 2002

Dark frames from orbiting infrared detector arrays are analyzed using a charge-collection model to investigate the effects of secondary and primary particle environments in infrared detectors and related electronics. The effects of different components of the primary and secondary environments are assessed by examining trends with time and pixel-to-pixel charge correlations. I. INTRODUCTION U SE OF sensitive infrared detectors in space poses significant challenges for the astronomy, military, and radiation-effects communities. These devices are designed to respond to the low levels of ionization deposited by infrared photons. This high detector sensitivity, coupled with the faintness of infrared sources typically observed by these detectors, necessitates that detectors operate at cryogenic temperatures, where charge mobilities are low and charges can become metastably trapped. As such, infrared detectors are susceptible to a rich variety of radiation effects that can be caused not just by proton-induced nuclear recoils and heavy ions but also by single low-LET (so-called minimum-ionizing) particles in the radiation environment [1]-[3]. Moreover, the faintness of most infrared sources of interest means that observations are often of long duration so there is ample opportunity for radiation effects to corrupt detector readings. Previous studies have reported significantly higher-than-expected rates of radiation-induced contamination in images Manuscript

mentioning

confidence: 99%

Characteristics of the Hubble Space Telescope's radiation environment inferred from charge-collection modeling of Near-Infrared Camera and Multi-Object Spectrometer dark frames

Ladbury

Gee

et al. 2002

“…Secondary particles include delta electrons and nuclear reaction by-products. There is experimental evidence of secondary particles interfering with IR telescopes from the on-orbit experience of the European Space Agency's Infrared Space Observatory (ISO) [4]. Measurement of transients in the ISO detectors indicated a transient rate approximately 80 % higher than could be accounted for by the primary particles.…”

Section: Energetic Particle Environmentmentioning

confidence: 99%

Radiation-induced charge collection in infrared detector arrays

Reed

Ladbury

et al. 2002

A modeling approach is described for predicting charge collection in space-based infrared detector arrays due to ionizing particle radiation. The modeling uses a combination of analytical and Monte Carlo techniques to capture the essential features of energetic-ion-induced charge collection to detector pixels in a two-dimensional array. The model addresses several aspects that are necessary for high fidelity simulation of complex focal plane array structures including multiple layers, sub-regions within layers, variation of LET with range, secondary electron scattering, free-field diffusion, and field-assisted diffusion. Example results are given and predictions are compared to experimental data.*

“…There is experimental evidence of secondary particles interfering with IR telescopes from the on-orbit experience of the European Space Agency's Infrared Space Observatory (ISO) [1]. Measurement of transients in the ISO detectors indicated a transient rate approximately 80% higher than could be accounted for by the primary particles.…”

Section: Introductionmentioning

confidence: 97%

Proton-induced secondary particle environment for infrared sensor applications

Reed

Marshall

et al. 2003

We present measurements of the proton-induced secondary particle environment in the vicinity of an infrared focal plane array. Measurements were made of the energy depositions from secondary electrons and scattered protons from the interior of a cryogenic test dewar using an infrared detector array. The results are compared with model predictions and analyzed for implications to space-based infrared sensors.