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Getting Started

The Wisconsin Ultraviolet Photo-Polarimeter Experiment (WUPPE) was the spectropolarimetry component of the three ASTRO instruments that flew on Space Shuttle missions in December 1990 and March 1995. A halfwave spectropolarimeter provided medium resolution spectropolarimetry for research into the interstellar medium, hot stars, stars with circumstellar material, interacting binary stars, novae, solar system objects, and active galaxies. A Lyot analyzer obtained low resolution observations of faint targets, but due to calibration problems did not produce scientifically useful data. The WUPPE instrument provides a unique data set, one of the few providing polarimetric data in the ultraviolet portion of the spectrum.

The MAST holdings include 238 WUPPE observations of 160 targets obtained with the halfwave spectropolarimeter. Of these, useful spectropolarimetric data are available for 121 targets. Ultraviolet spectrophotometry only is available for the remainder. The data cover a wavelength range from 1400 to 3300 Å, with a spectral resolution of 16 Å. The flux calibration is based primarily on the original IUE (IUESIPS) flux calibration. The polarization was calibrated on the ground and in flight, the latter by observing stars known to be unpolarized in the visible and by observing heavily polarized stars with nearly simultaneous ground-based polarimetric observations.

The search form may be used to select data from the WUPPE catalog by object name, coordinates, type of object, date of observation, etc. Click on the Entry ID to view the spectrum, degree of polarization, and polarization position angle plotted as functions of wavelength.

The data are archived as FITS files. In addition, ASCII files of the data and Postscript plots depicting the polarization and spectrum are provided as part of the standard data product. See Data Products and Reading WUPPE Files for more information.