Bibcode
Crivellari, L.; Morossi, C.
Bibliographical reference
Astronomy and Astrophysics, Vol.106, P. 332, 1982
Advertised on:
2
1982
Journal
Citations
4
Refereed citations
4
Description
This paper presents an alternative procedure which extracts spectra from
IUE low resolution images. The -by-line image is scanned perpendicularly
to the direction of dispersion . The resulting cross-cuts are then
fitted with a known-form analytical function, which consists of a linear
base-line describing the background plus as many bands as there are
spectra in the image under study. At each wavelength point the value of
the spectrum is assumed to be the area of the corresponding band. A
proper choice of the band profile allows us to recover the light
scattered perpendicularly to the direction of dispersion, due to the
"halation" effect in the on-board UV-to-visible image converter. In such
a way a more correct extracting procedure is achieved. It furnishes
noticeably better results than the standard VILSPA extracting routine in
the case of highly exposed images. As a by-product, some properties of
the Point Spread Function perpendicular to the direction of dispersion
are determined.