Fringe Correction for STIS Near-IR Long-Slit Spectra using Contemporaneous Tungsten Flat Fields

Session 18 - STIS.
Display session, Wednesday, January 07
Exhibit Hall,

[18.03] Fringe Correction for STIS Near-IR Long-Slit Spectra using Contemporaneous Tungsten Flat Fields

P. Goudfrooij, S. A. Baum (STScI), J. Walsh (ESA/ST-ECF), P. Plait (ACC)

We report on the accuracy of fringe removal for STIS long-slit near-IR spectra using contemporaneous flats (taken during the course of science data collection). In case of point sources, we use tungsten flats taken through a small slit to mimic illumination by a point source. In case of extended sources, we use long-slit spectra of Jupiter's moon Io as test cases. We find that in case of the G750L grating, fringe residuals can be reduced to below the 1% level, for both point sources and extended objects. We will also compare these results with those obtained by using a library of long-slit in-flight flats whereby the fringes in the flats are matched to observed spectra by cross-correlation.

Program listing for Wednesday