MOPEX User's Guide - IRSA

MOPEX User’s Guide
Mosaic PRF File Name: The name of the PRF file to be used for source detection in the
mosaic. Since APEX Multiframe carries out the source extraction on the stack of input
images, not the mosaic, this does not have to be perfect. For IRAC data, the PRF for the
center of the array will usually suffice, while for MIPS, there is a mosaic PRF supplied.
These can be found in the /cal/ directory.
Probability Threshold: (float from 0.0 to 1.0, default = not set). If the Point Source
Probability image is used for detection, it is in principle possible that a large proportion of
pixels will have values close to 1, which is the maximum. The calculation of the initial
detection threshold could be skewed upward by these high values with a possible result of no
detections. If this parameter is set, values larger than Probability Threshold will not be
inc luded in the initia l threshold calculation. This is an unlikely scenario, and this parameter
generally does not need to be set.
Use PSP to Detect: This parameter determines which image should be used as input to the
Detect module.
Delete Intermediate Files: Check this to delete all of the intermediate files created by the
APEX pipeline. This leaves only the input files and the files created by the final module. This
is useful for saving disk space once you are satisfied with your reduction setup. Note that
MOPEX will prompt you with a pop-up dialogue box when you run the flow, to be sure that
you meant to select this irreversible option.
Use Background Subtracted Image for Fitting: If checked, the background subtracted
version of the image created by the Extract MedFilter module is used for PRF fitting.
Use Background Subtracted Image for Aperture: If checked, the background subtracted
version of the image created by the Extract MedFilter module is used for aperture photometry
The Aperture Photometry module can perform an annular background subtraction, so it may
be better not to use this option.
Use Data Uncertainties for PRF-fitted SNR: If checked, APEX will use the data
uncertainties for calculating the PRF-fitted SNR. The default is off, in which case it will use
the current Gaussnoise noise estimate (i.e. basically the background RMS).
Create Standard Deviation Mosaic: If checked, the Mosaic CoAdder module will create the
standard deviation mosaic.
Create UNC Mosaic: If checked, the Mosaic CoAdder module will create a mosaic of the
input (or S/N Estimator generated) uncertainties.
Point Source Extraction (APEX) 109
APEX Modules