II. The WISE All-Sky Data Products

3. Atlas Images

h. Full-Depth Ecliptic Polar Atlas Images

1. Description and Contents
2. Access the WISE Full-Depth Ecliptic Polar Atlas Image Sets

i. Description and Contents

The WISE survey scanning strategy produced frameset depth-of-coverage that increased with increasing ecliptic latitude. Typically, 12 independent Single-exposures were accumulated at each point on the sky near the Ecliptic plane, and over 3000 exposures were obtained directly at the north and south Ecliptic poles. The extremely large number of framesets involved with Tiles near the Poles exceeded the processing memory and runtime capabilities for source extraction, so coverage was artificially limited to an average depth of approximately 160 framesets for 41 Tiles near the Ecliptic poles (20 in the north and 21 in the south) during the Multiframe Pipeline processing that produced the All-Sky Image Atlas and Source Catalog.

Although source extraction using all available Single-exposure framesets was not feasible for these 41 Tiles, the full-depth coadded image products were constructed using all framesets that satisfied the basic selection criteria described in V.2.c. These full-depth image sets are provided to augment the basic All-Sky Atlas Images.

The WISE Full-Depth Ecliptic Polar Atlas Images are 4095x4095 pix @1.375"/pix FITS format image sets. One image set is produced for each of the 41 Atlas Tiles for which coverage was attenuated for the All-Sky Atlas and Source Catalog. Each image set consists of:

• Intensity images - Four spatially registered images, one in each of the WISE bands, produced by coadding multiple 7.7 sec (W1 and W2) or 8.8 sec (W3 and W4) single-exposure images covering the Atlas Tile area. Pixel outlier rejection is used during coaddition to suppress transient events such as cosmic rays, hot pixels, satellite trails and other fast moving sources.


• Depth-of-coverage maps - Four images, one in each WISE band, that provide the realized exposure coverage for each pixel in the corresponding coadded intensity images following outlier rejection.


• Uncertainty maps - Four images that give the propagated 1-σ uncertainty estimate for each pixel in the corresponding coadded intensity images. The uncertainty maps are used for proper error estimation when making aperture photometry measurements on the Atlas Intensity Images.

The Full-Depth Polar Atlas Images and maps are in the Flexible Image Transport System (FITS) format and follow the World Coordinate System (WCS) standard for astronomical image data.

The Full-Depth Ecliptic Polar Atlas Image products have filenames that follow the same convention as the All-Sky Atlas Images:

• Intensity image:   COADDID-wBAND-int-3.fits


• Depth-of-coverage image:   COADDID-wBAND-cov-3.fits


• Uncertainty image:   COADDID-wBAND-unc-3.fits

where BAND = 1, 2, 3, or 4, and COADDID is a unique identification string pertaining to the sky footprint (see II.2.a). The disambiguation string in the COADDID is ab42 for Full-Depth Polar Atlas Images (it is ab41 for the All-Sky Atlas Images). The Full-Depth Polar Atlas Image FITS header content is the same as for the All-Sky Atlas Images, and is described in II.3.b.

Because the Full-Depth Polar Atlas Images were generated using the same algorithms as the All-Sky Release Atlas Images, they are subject to the same issues and limitations. Please read the Cautionary Notes for the All-Sky Release Atlas Images.

Access to the Full-Depth Ecliptic Polar Atlas Image sets, along with cross-reference tables that contain the individual framesets used in each coadd, is availabe via the links in Table 1, below.

ii. Access the WISE Full-Depth Ecliptic Polar Atlas Image Sets

You may retrieve the image data and Atlas/Frame cross-reference information files for the 41 Full-Depth Ecliptic Polar Atlas Tiles using Table 1 below.

• The COADDID column identifies the Full-Depth Atlas Tile.


• Click on the links in the Image Products column to download a tar file that contains the gzip'd Intensity Images, Depth-of-coverage maps, and Uncertainty maps for each Tile. CAUTION: These tar files are 400-450MB in size.


• Click on the links in the Atlas/Frame Cross Reference Tables column to download an ascii table that contains a listing of all Single-exposure framesets that overlap the footprint of the Atlas Tile. For each frameset entry, there are 4 columns corresponding to the four WISE bands that indicate if the band-frames were used in the Full-Depth coadd. Band-frames that were used are marked "ok", and those that were rejected are marked with a code that gives the reason for the rejection (e.g. "score" - Frame quality score is zero; "moon" - scattered moonlight; "anneal" - (W3 and W4 only) the frame was taken less than 2000 sec following a Si:As detector anneal).



Table 1 - WISE Full-Depth Ecliptic Polar Atlas Image Products

COADDID	Image Products	Atlas/Frame Cross Reference Tables
0825m637_ab42
0838m652_ab42
0853m667_ab42
0858m637_ab42
0870m682_ab42
0873m652_ab42
0879m697_ab42
0890m667_ab42
0891m637_ab42
0908m652_ab42
0909m682_ab42
0920m697_ab42
0924m637_ab42
0927m667_ab42
0943m652_ab42
0949m682_ab42
0962m697_ab42
0964m667_ab42
0978m652_ab42
0988m682_ab42
2610p681_ab42
2621p651_ab42
2635p666_ab42
2642p636_ab42
2650p681_ab42
2656p651_ab42
2672p666_ab42
2675p636_ab42
2679p696_ab42
2690p681_ab42
2691p651_ab42
2708p636_ab42
2709p666_ab42
2721p696_ab42
2726p651_ab42
2729p681_ab42
2741p636_ab42
2746p666_ab42
2761p651_ab42
2769p681_ab42
2783p666_ab42

Last update: 2012 February 21