***NEW*** Note that with version 18.5.0 one can use multiprocessing to speed up MOPEX tasks. The tasks Overlap, Mosaic, Apex (Multi) and Apex User List (Multi) now allow multiprocessing of some steps. In the GUI, this is set in Initial Setup, Multi-Processing Mode. The options are "on", "off", and "manual". The default is "on" -- this grabs 3/4 of the available processors. Setting "manual" lets the user set the number of processors used. You should see speed-ups of at least 2x.
If using command-line, add these lines at the top of your namelist:
do_multiprocess = on | off | manual default = off
ncpu_multiprocess = 1 default = 1
If "manual" is set, set ncpu_multiprocess to the number of processors to use.
6.5.2 APEX Modules: APEX Multiframe and APEX User List Multiframe Settings
Command Line Equivalent: N/A
Default Output Directory: N/A
Depends On: Initial Setup
Relevant Pipelines: APEX Multiframe; APEX User List Multiframe
PURPOSE
To set the input parameters specific to the APEX Multiframe and APEX User List Multiframe pipelines. Parameters that are specific to only one of these pipelines are marked.
INPUT
User Input Fixed Positions Table File Name: (User List only)The input file containing the list of user-specified positions for source extraction. See §8.10 for more information.
Use Input List Type: (User List only) The type of positional input listed in the User Input Fixed Positions Table File. Options are 0 - positions in [x,y] (pixels); 1 - positions in [RA,Dec] (degrees) or 3 - positions in both [x,y] & [RA,Dec].
Pixel by Size: Check this to set the output pixel size in degrees. The default pixel size depends on the instrument and channel: see the templates for the default sizes.
Pixel Size X (deg): Set the X-size of the output pixels in degrees. The pixel size in the X-direction is quoted as a negative value to comply with convention. A positive value will generate an error message.
Pixel Size Y (deg): Set the Y-size of the output pixels in degrees.
Pixel By Ratio: Check this to set the output pixel size by ratio of the input pixel to the output pixel, i.e. to make the output pixels half the size of the input pixels (over-sample the mosaic), set the values of Pixel Ratio X(Y) = 2. The ratio is taken after correction for geometric distortion.
Pixel Ratio X: Set the pixel ratio in the X-direction.
Pixel Ratio Y: Set the pixel ratio in the Y-direction.
Use PRF File Name: Use a single fixed PRF file for fitting all sources in the field of view. PRF files are provided for both IRAC and MIPS, or you can use PRF Estimate to generate your own PRF from the data (not recommended for IRAC - see Chapter 7). The PRF files for MIPS and for the center of the IRAC arrays can be found in the <mopex_dir>/cal/ directory.
Use PRF Map File Name: Use a variable PRF map file, which allows the use of different PRFs depending on the location of the source on the array. See §8.7 for the format of the PRF Map file. If you wish to use a PRF Map file for IRAC, you will need to download the full list of IRAC PRF files from the website.
PRF File Name: The name of the PRF file to use for source fitting.
PRF Map File Name: The name of the PRF Map file to use for source fitting.
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 <mopex_dir>/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 included in the initial 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.
Use Standard Deviation to Detect: If checked, the standard deviation mosaic is used as the uncertainty estimate in image segmentation.
Use Uncertainty to Detect: If checked, the uncertainty mosaic is used as the uncertainty estimate in image segmentation.
Sigma Weighted Coadd: If checked, the input uncertainties will be used as weights by the Mosaic CoAdder module.
Use Refined Pointing: Check this to use the alternate FITS pointing keywords created by the offline pointing refinement script (pointing_refine.pl). Do not switch this on unless you have manually run pointing refinement outside of the normal BCD pipeline products. Most users will never use this option, as pointing refinement is not recommended for Spitzer data. If you believe that there is a problem with the pointing of your data with respect to e.g. the 2MASS catalog, please email the Spitzer Helpdesk for assistance.
Use Bright Object Mask: Select this option to use the object mask generated by the Bright Detect module in the full image segmentation.
COMMAND LINE INPUT
The following parameters are set in the Global Parameters part of the namelist. Note that if both MOSAIC_PIXEL_SIZE_X(Y) and MOSAIC_PIXEL_RATIO_X(Y) are both set, the former takes precedence and will override the latter.
