DEEP2 Galaxy Redshift Survey


The observations included in DR4 span a total of 411 slitmasks. For reference, we provide a table summarizing the basic information regarding each of the masks, including observation date, slitmask position and orientation, number of objects, and rough estimates of seeing and signal-to-noise. For more details, refer to Table 9 of Newman et al. (2013).

Data Release 4

DEIMOS Slitmask Design Information

In addition to 1-d and 2-d spectra and a complete redshift catalog, DR4 includes the design parameters for each DEIMOS slitmask. This design information, including the position and dimension (PA, length, width, etc.) of each slitlet, the objects placed in each slitlet, and much more, is stored in the “bintabs” files produced as part of the spec2d data reduction pipeline. For each slitmask, there is a separate “bintabs” file (e.g., “3206.bintabs.fits”), containing several binary tables:

  1. (1)ObjectCat

  2. (2)MaskDesign

  3. (3)DesiSlits

  4. (4)SlitObjMap

  5. (5)MaskBlu

  6. (6)BluSlits

  7. (7)Observers

  8. (8)PhotCat

These tables (and the slitlets and objects on the slitmask) are linked through multiple common identifiers (e.g., OBJECTID and DESID). Brief descriptions of the different tables are given here along with code for matching up the various entries in a more user-friendly manner.

The “bintabs” file for a given slitmask is identified by the filename, which follows the naming convention of “mmmm.bintabs.fits.gz”, where mmmm = the 4-digit slitmask number as given in Table 9 of Newman et al. (2013). To ease download, these mask design files are grouped in a single tarball:

Mask Design Info (“bintabs” files): deep2.dr4.bintabs.tar

When unpacked (e.g., using the command “tar xvf deep2.bintabs.tar”), the tarball will create a subdirectory named “deep2_bintabs_files”, which will contain the “bintabs” files for all of the DEEP2 DR4 slitmasks.