National Aeronautics and Space Administration

WASS Archive Access

The Wisconsin All-Sky Survey (WASS) archive includes :
High level products: The data associated with the WASS are all-sky maps in FITS in the seven different energy band and a FITS table containing the effective area for each of the energy band. The maps are in galactic coodinates using an Aitoff projection and contain cont rate obtained. One of flight 25.045 (Mar 1979) had a mulfuctioning attitude system and data collected in the B and C band were not used.
Counts in each energy band were binned into 0.2 s intervals, when the payload pointing direction moved at most 1.1°, and a dead-time-corrected cosmic-ray background rate was subtracted. The pointing direction was determined for the middle of each interval, and a conical approximation to the collimator response was used to weight all pixels within the field of view. The net counts were then divided up among the pixels according to these weights. The 0.2 s observing time, corrected for electronic dead-time and atmospheric transmission, was similarly divided and stored in a second array. These count rate maps were produced by dividing the counts map by the exposure time map. ( McCammon et al. 1983, ApJ 269,107M)

Strong X-ray discrete source were removed from the maps. These are :

The pictures below of the sky maps and effective area link to the FITS image data in the WASS archive at the HEASARC

Maps

Effective area