The Wide-field Infrared Survey Explorer at IPAC

Frequently Asked Questions

CAUTION: The WISE Preliminary Data Release products are superseded by the products from the March 2012 WISE All-Sky Data Release.

Users are strongly advised to read the Cautionary Notes section of the Explanatory Supplement to the WISE Preliminary Data Release Products before using WISE Image and Source Catalog information.

1. WISE Data Access

• How do I access WISE data?

Access modes for the WISE data products are described in section I.3 of the WISE Explanatory Supplement.

• When will it be possible to download the entire WISE Preliminary Release Source Catalog?

The WISE Source Catalog is now available for bulk download via the NASA/IPAC Infrared Science Archive at

http://irsadist.ipac.caltech.edu/wise-prelim/

See section I.3 of the WISE Explanatory Supplement for a general description of WISE data access modes.

Interactive queries on any column or combination of columns in the WISE Source Catalog can be made using the IRSA/Gator General Catalog Search service. However, the return file size limit from Gator queries is ~2GB, so it is not designed for full Catalog downloads.

2. Photometric System and Calibration

• Can I get the relative spectral response curves for the WISE bandpasses?

The WISE filter bandpasses are described in section IV.3.g.v of the WISE Preliminary Release Explanatory Supplement. The filter bandpass relative spectral response (RSR) curves are shown graphically in Figures 4a and 4b, and can be downloaded in ASCII table format from links in the captions to those two figures.

• How do I convert WISE Source Catalog or Single-exposure Source Database magnitudes to AB magnitudes and flux densities?

WISE Catalog and Single-exposure Source Database magnitudes are given in the Vega system and represent total in-band brightness measurements. Conversion of WISE in-band magnitudes to monochromatic values such as flux density or AB magnitude is described in section IV.3.g.v of the WISE Explanatory Supplement. The broad WISE bandpasses may necessitate significant color corrections when deriving monochromatic brightnesses depending on the spectral energy distribution of the particular object. The nominal system flux zero points are defined for a f_ν∝ν^-2 spectrum through the WISE bandpasses. Color corrections for other spectral slopes are given in section IV.3.g.vi of the Supplement.

3. General

• Were any quality filters applied to the 2MASS PSC objects that were positionally associated with WISE Source Catalog and Single-exposure Source Database entries?

No quality filters were applied to the 2MASS PSC entries before positionally associating them with the WISE Source Catalog and Single-exposure Source Database entries. Associations were made with the full composite 2MASS All-Sky PSC, that includes the high reliability Catalog and the lower signal-to-noise extension (see section I.6.b.i of the 2MASS All-Sky Data Release Explanatory Supplement).

Last update - 2013 August 27         Contact the WISE Help Desk