January 7, 2006  FLAMEX Public Data Release DR1  (Cetus)

The DR1 release for the Cetus region is now complete. The file formats
are the same as for Bootes. There is one noteworthy difference between
the two catalogs, which relates to the completeness simulations. For the
Bootes region the effective radii of the simulated galaxies were 0.07-0.5
arcsec (0.5-4.0 kpc at z=1). In the current release of the Cetus data the
effective radii of the simulated galaxies are 0.23-1.1 arcsec, with the
expectation that we will eventually also run a set of simulations for Bootes
with this new range of effective radii. The differences in effective
radii for the two survey regions should have a minimal effect for most
applications. If you are concerned about the impact for your particular 
project, please contact me (anthony@astro.ufl.edu) and I will be happy to 
assist.


September 30, 2005.  FLAMEX Public Data Release DR1 (Bootes)

DR1 includes the J and Ks catalogs resulting from the FLAMINGOS
Extragalactic Survey (FLAMEX). As noted on the web page, the Bootes
data is available today; the Cetus data will be available shortly.
For an overview of the survey observations and data reductions we
refer the reader to Elston et al. 2005, which has been submitted to
ApJ. The current draft of this paper is posted on the publications
page, with the large warning that this is indeed a draft that has not
yet been accepted.  If you refer to this paper, please check back in a
few weeks for an updated version to confirm that there have been no
substantive changes. Additional questions about the survey procedures
can be addressed to Anthony Gonzalez.


The .tgz files on the web page contain the matched J and Ks catalogs
for the survey. The survey is Ks-selected, with the J catalog
generated using SExtractor in dual image mode. The headers should be
mostly self-explanatory, but there are a few items that warrant
clarification:

Column 0 (Galaxy IDs): The first column contains a unique galaxy
identification number for each source. This is included for utility,
but for publication the standard coordinate naming convention is
preferred, with the prefix FLX J.

Column 1 (Subfields): The alphanumberic naming convention in this
column identifies the specific subfield in which the object was
detected. This is useful for quantifying field-to-field variations,
but otherwise likely of limited interest to most people. Those
interested in more information on the subfield naming convention may
contact the FLAMEX team.

Columns 2-82: These columns correspond to the standard SExtractor
outputs and as such should be self-explanatory. Beware that the
RUNNING_ID_NUMBER in column 2 refers to a given subfield and does not
uniquely identify an object within the full catalog. Also, WE STRONGLY
CAUTION YOU NOT TO USE THE 1.5"-3" APERTURE MAGNITUDES FOR OBJECT
PHOTOMETRY!  The FLAMINGOS instrument has intrinsic aberrations that
cause the psf to vary significantly across the field, and these
apertures are too small to produce robust photometry across an entire
subfield. They are of interest only in some technical applications
(like quantifying this variation).

Column 83: This column provides the relative exposure weight of the
image at the location of the object detection (xpeak,ypeak) normalized
to a maximum value of 1.0. This exposure weight is used in computing
the completeness limits for each object

Column 84-108: These columns contain quantities derived from our
completeness simulations.  In columns 84-97 we provide our best
estimates of the photometric uncertainties as derived from these
simulations. Note that these values are systematically larger than the
output of SExtractor.  In column 98-107 we provide the 50%
completeness limit at the location of each object for the AUTO and
aperture magnitudes. Note that we do not provide completeness limits
for apertures smaller than 4" for the reasons discussed
above. Finally, column 108 contains the computed object detection
probability based upon the 6" aperture magnitude and detection limit.


For all of the above quantities, we defer to the user to exercise
appropriate judgement with respect to significant digits. For the
derived quantities in particular the current format gives much higher
precision that is warranted.


Enjoy.