Astron. Astrophys. Suppl. Ser.
Volume 139, Number 1, October I 1999
|Page(s)||183 - 197|
|Published online||15 October 1999|
The IUE INES System: Improved data extraction procedures for IUE
Departamento de Física, Universidad Europea de Madrid, C/Tajo S/N, 28670 Villaviciosa de Odón, Spain
2 LAEFF, P.O. Box 50727, 28080 Madrid, Spain
3 ESA - XMM SOC, P.O. Box 50727, 28080 Madrid, Spain
4 ESA - IUE Observatory, P.O. Box 50727, 28080 Madrid, Spain
Send offprint request to: P.M. Rodríguez-Pascual
Accepted: 28 June 1999
We present the extraction and processing of the Low Dispersion spectra within the framework of the ESA "IUE Newly Extracted Spectra” () System. Weak points of , the optimal extraction implementation to produce the output products (extracted spectra) are discussed, and the procedures implemented in to solve these problems are outlined. The more relevant modifications are: 1) the use of a new noise model, 2) a more accurate representation of the spatial profile of the spectrum and 3) a more reliable determination of the background. The extraction also includes a correction for the contamination by solar light in long wavelength spectra. Examples showing the improvements obtained in with respect to are described. Finally, the linearity and repeatability characteristics of data are evaluated and the validity of the errors provided in the extraction is discussed.
Key words: methods: data analysis / space vehicles / techniques: image processing / ultraviolet: general
© European Southern Observatory (ESO), 1999