First Data Release (DR1) Data Products, Version 2
The NDWFS first data release (DR1_02) consists of dithered and stacked, photometrically and astrometrically calibrated FITS images in three bands (Bw, R, and I) for four NW sub-fields of the Boötes Field of the NOAO Deep Wide-Field Survey.
A FITS image and three associated IRAF FITS masks are available for each of the bands in each of the four fields comprising the DR1_02 data release. These files can be downloaded by clicking on the fields of the following table. Note these are large files! The FITS images are 300+ MB each. An image cutout function will be available shortly which will allow image regions of arbitrary size to be created on-the-fly and downloaded via the web.
| Field | Bw | R | I |
|---|---|---|---|
| NDWFSJ1426p3456 | Image BPM EXP NREJ |
Image BPM EXP NREJ |
Image BPM EXP NREJ |
| NDWFSJ1426p3531 | Image BPM BPM NREJ |
Image BPM EXP NREJ |
Image BPM EXP NREJ |
| NDWFSJ1428p3456 | Image BPM EXP NREJ |
Image BPM EXP NREJ |
Image BPM EXP NREJ |
| NDWFSJ1428p3531 | Image BPM EXP NREJ |
Image BPM EXP NREJ |
Image BPM EXP NREJ |
Access to the NDWFS DR1_02 data products is also available via the NOAO archive FTP server.
The FITS images and IRAF pixel masks available above are named according to the following convention:
NDWFSJrrrrpdddd_f_id.fits
where
| "NDWFS" | Stands for the NOAO Deep Wide-Field Survey |
| "J"rrrrpdddd | Denotes the IAU J2000 RA and DEC of the sub-field of the survey and does not necessarily match the image center position, which is defined in the image header World Coordinate System |
| f | Indicates the filter (Bw, R, or I) |
| id | Indicates the version number of the released data. If any changes are made to released images any such changes will be logged on these web pages |
Files with the "_nrej.fits" suffix are "rejection mask" files. For a given pixel in the combined image, the value of NCOMBINE (one of the header keywords) minus the value of the associated pixel in the rejection mask indicates the number of images that contributed to the value of that pixel in the combined image. These are similar to the "_rjm.pl" files of the version 1 release except they are in FITS rather than IRAF "pixel list" format.
The "_bpm.fits" files are "bad pixel mask" files. Any region where valid data contributed to the stack has a value of 0 while the remainder of the mask has a value of 1. Regions found in the bad pixel mask are typically edges of the field and "bleed trails" of saturated pixels from bright stars.
Files with the "_exp.fits" suffix are "exposure mask" files. They contain the net exposure time in seconds for a given region of an image. The net exposure time varies across the image due to the rejection of bad pixels and dithering. Regions where the exposure mask values vary significantly include edges of the subfields and areas which fell between the mosaic camera CCD chips in several images contributing to the final stacks.
NOAO Deep Wide-Field Survey -- Last modified: February 29 2016 16:18:52. -- Feedback: buelljannuzi@email.arizona.edu
Updated on May 14, 2024, 1:42 pm