Analysis of ISOPHOT chopped observations

P. Ábrahám, J. A. Acosta-Pulido, U. Klaas, S. Bianchi, M. Radovich, L. Schmidtobreick

Research output: Conference contribution

Abstract

Chopping between the source and 1 or 2 background positions was an ISOPHOT observing mode for faint source photometry. More than 7000 observations of this type were performed during the mission. We review the main instrumental effects related to chopping, and describe the data reduction steps and calibration strategies developed for this mode. A robust signal processing has been invented which allows to derive reliable difference signals from a chopped pattern. Signal losses dependent on chopper frequency and flux change have been assessed from comparison with staring observations. Chopper offsets have been investigated from the analysis of non-detection measurements. The current data reduction scheme, as implemented in the automatic processing of OLP10, achieves accuracies in general better than 30%. Far-infrared observations of faint sources close to the detection limit may have higher uncertainties, partly due to cirrus confusion which is a severe limitation of this observing mode.

Original languageEnglish
Title of host publicationEuropean Space Agency, (Special Publication) ESA SP
Pages89-94
Number of pages6
Edition481
Publication statusPublished - máj. 2003
EventThe Calibration Legacy of the ISO Mission - madrid, Spain
Duration: febr. 5 2001febr. 9 2001

Other

OtherThe Calibration Legacy of the ISO Mission
CountrySpain
Citymadrid
Period2/5/012/9/01

Fingerprint

Data reduction
Photometry
Signal processing
Calibration
Fluxes
Infrared radiation
Processing
Uncertainty

ASJC Scopus subject areas

  • Aerospace Engineering

Cite this

Ábrahám, P., Acosta-Pulido, J. A., Klaas, U., Bianchi, S., Radovich, M., & Schmidtobreick, L. (2003). Analysis of ISOPHOT chopped observations. In European Space Agency, (Special Publication) ESA SP (481 ed., pp. 89-94)

Analysis of ISOPHOT chopped observations. / Ábrahám, P.; Acosta-Pulido, J. A.; Klaas, U.; Bianchi, S.; Radovich, M.; Schmidtobreick, L.

European Space Agency, (Special Publication) ESA SP. 481. ed. 2003. p. 89-94.

Research output: Conference contribution

Ábrahám, P, Acosta-Pulido, JA, Klaas, U, Bianchi, S, Radovich, M & Schmidtobreick, L 2003, Analysis of ISOPHOT chopped observations. in European Space Agency, (Special Publication) ESA SP. 481 edn, pp. 89-94, The Calibration Legacy of the ISO Mission, madrid, Spain, 2/5/01.
Ábrahám P, Acosta-Pulido JA, Klaas U, Bianchi S, Radovich M, Schmidtobreick L. Analysis of ISOPHOT chopped observations. In European Space Agency, (Special Publication) ESA SP. 481 ed. 2003. p. 89-94
Ábrahám, P. ; Acosta-Pulido, J. A. ; Klaas, U. ; Bianchi, S. ; Radovich, M. ; Schmidtobreick, L. / Analysis of ISOPHOT chopped observations. European Space Agency, (Special Publication) ESA SP. 481. ed. 2003. pp. 89-94
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AU - Radovich, M.

AU - Schmidtobreick, L.

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