The data products from the SHELA program include both images and catalogs.

Images

The image files have names of the form ch1s_wavg.fits, where the rubric is:

• ch1s = "ch1" = IRAC channel 1 (3.6 micron) and "s" = stack of epochs 1+2+3. Replace ch1 with ch2 for IRAC 4.5 micron.
• wavg = "weighted averaging" was used for the stack
• the _wht extension indicates the weightmap (proportional to the exposure time in each pixel).
• a prefix "ep#" indicates that the image is from a single epoch, for example "ep1" = epoch 1.

There are eight images per band - a science image and weight map for each of three epochs as well as the combined multi-epoch images. Units of the science images are 15.06 microJy/ADU (magnitude zero point of 20.9555). Units of the weight images are 23.6 seconds.

Catalogs

The catalogs can be queried with the Catalog Search tool, and are stored as binary fits tables and IPAC ascii tables. The column definitions are discussed in Papovich et al. (2016). The files have the following names:

• shela_irac_v1.2_flux_cat.fits -- the catalog including 3.6 and 4.5 micron photometry for sources from the 3 epoch, combined images.
• shela_irac_ep#_v1.2_flux_cat.fits -- the catalog with 3.6 and 4.5 micron photometry from the individual epoch images, where # = 1, 2, or 3 for the first, second, and third epoch, respectively.