Search Publications

Deglitching methods by the ISOPHOT Interactive Analysis (PIA)

Gabriel, C.; Acosta-Pulido, J. A.

The ISOPHOT detectors were continuously exposed to high energy cosmic particles hits, resulting in an average hit rate frequency of an event per every 7 s. The net effect is a disturbance of the readout voltages, which decreases the signal-to-noise ratio and hence the photometric accuracy level. Thanks to the highly redundant readout method of ISO…

Cosmic Ray Effects on the ISOCAM Long Wave Detector

Claret, A.; Dzitko, H.; Engelmann, J.

The ISOCAM detector is subjected to transient effects induced by cosmic rays, the so-called glitches. This paper is focused on the ISOCAM long wave detector. The predicted glitch rates have been re-evaluated by taking into account secondary particles production in the materials surrounding the LW detector. We show in this preliminary study that th…

Ultimate sensitivity with ISOCAM

Altieri, B.; Aussel, H.; Elbaz, D. +3 more

We discuss the instrumental factors which constrain the sensitivity limits of the mid-infrared camera (ISOCAM) of ESA's Infrared Space Observatory (ISO). The observing strategy judged to be best suited to faint-source detection is described. A data analysis technique adapted to the extraction of the faintest point-sources is discussed. We report t…

SWS-Detector Glitch Effect Correction

Wiezorrek, E.; Wieprecht, E.; Haser, L.

We describe how the ISO-SWS (Infrared Space Observatory - Short Wavelength Spectrometer) software packages detect various glitch events i.e. high energy particle hits effecting the SWS detectors. A rough classification of glitch types is given. The events cause an instantaneous change in the slope of the SWS detector read outs followed by a distor…

ISOCAM Long Wave Detector Glitches: Data and Ray-Tracing Simulations

Nieminen, Petteri; Sørensen, John

The affected pixel number distribution of the ISOCAM Long-Wave (LW) detector in cosmic ray-induced glitches is calculated. The methods employed are Monte Carlo ray-tracing techniques and the taxi metric, which allows direct calculation of the affected pixels based on the knowledge of entry and exit points of the ray. The simulation results are com…

Recognition of Space Weather Impact on the Isophot Detectors

Klaas, Ulrich; Castañeda, Hector O.

The effects of changes in the space environment on the ISOPHOT photoconductive detectors over the whole ISO mission were studied using the complete set of responsivity check measurements taken after the curing of the detectors. We found that the responsivity of the Ge-based, low bias voltage far-infrared detectors (P3, C100, and C200) is sensitive…

The ISOCAM Detectors: an Overview

Gallais, P.; Boulade, O.

The two detectors of the ISOCAM camera on board the ISO spacecraft, have performed nominally for the entire duration of the emission. Their main properties (dark current, noise and responsivity) stayed very stable from the first tests on ground to the end of the life of ISO, a 6 yr long period. The main limitation to the sensitivity of the observa…

Summary of ISO Detector Workshop

Young, Erick T.

The Infrared Space Observatory successfully carried out a wide range of astronomical observations in the wavelength range 2.4 µm to nearly 200 µm. To cover this extremely broad range, a variety of detector technologies were used by the instruments teams. As such ISO also proved to be an important test bed for the operation of these det…

HIPPARCOS and the Future of Space Astrometry

Perryman, M. A. C.

Charged-particle induced background expected in X-ray detecting CCDs in highly eccentric earth orbits

Danner, R.

Charged particle fluxes on satellites in highly eccentric Earth orbits are studied, using data from ISEE1 and EXOSAT missions. The effects of minimum-ionizing particles, low-energy electrons and secondary radiation produced by these particles on CCDs used as X-ray detectors are identified. A technique to discriminate events caused by minimum-ioniz…