This section gives a full listing and description of all the input and output parameters available in Bandmerge. An annotated example of a Bandmerge primary namelist can be found in Appendix A. A similar example of a secondary namelist (essentially a subset of the primary namelist) can be found in the same section. See §2.2 for an explanation of the namelist types. The namelist is split into two sections – Global Parameters and Module Parameter Block. The primary namelist contains both sections, while the secondary namelists only include the Module Parameter Block section.
IMPORTANT NOTE: all input variables in the namelists require a space preceding and following the equals sign, i.e. "variable = value". An entry like "variable=value" will not be read and the hard-coded default will be used. You will not be warned that your input value is not being read.
3.1 Global Parameters
These are the parameters listed at the top of the namelist, and control the input and output flow for the Bandmerge Perl script. The variables for input into the Bandmerging algorithm are given in §4.2 Module Parameter Block.
run_bandmerge = 1 (switch)
Run the Bandmerge module. This must be set to 1. If set to 0, Bandmerge will not run.
convert_sky_to_cartesian = 1 (switch)
Convert the source positions from RA and Dec into Cartesian coordinates for source matching. Necessary if your input source lists give positions in RA and Dec. To turn this off, set convert_sky_to_cartesian = 0. See also convert_cartesian_to_sky.
convert_cartesian_to_sky = 1 (switch)
Convert the calculated source positions from Cartesian coordinates used internally by Bandmerge into RA and Dec for the final source output list. Set to 0 to get the output source list in X and Y instead of RA and Dec.
File name of the input source detection tables. The namelist should contain a separate similar line for each input table, e.g.
PointSourceList_Filename1 = irac1_extract.tbl
PointSourceList_Filename2 = irac2_extract.tbl
PointSourceList_Filename3 = mips70_extract.tbl
etc…
Instrument_Channel* = <Instrument and channel number> (string)
A line for each of the input source detection tables telling Bandmerge which instrument and channel the data were taken with. Unless the table headers list the INSTRUME and CHNLNUM keywords, you must include these lines for each input table e.g.
Instrument_Channel1 = IRAC_1
Instrument_Channel2 = IRAC_2
Instrument_Channel3 = MIPS_2
etc…
MIPS-24, MIPS-70 and MIPS-160 are referred to as MIPS_1, MIPS_2 and MIPS_3, respectively. IRAC channels 1, 2, 3 and 4 refer to 3.6, 4.5, 5.8 and 8.0 microns, respectively. If your data were not taken with Spitzer then you must still assign them a Spitzer instrument and channel number to fool the Bandmerge software into running properly.
FIF_FILE_NAME = <name of Fiducial Image Frame table> (string)
File name of the input Fiducial Image Frame table (see §2.4). Either this keyword or REFERENCE_FITS_FILENAME is required.
REFERENCE_FITS_FILENAME = <name of reference FITS image> (string)
File name of the FITS image to be used as the common coordinate reference image (see §2.4). Either this keyword or FIF_FILE_NAME is required.
File name of the initial Bandpair Uncertainty File (see §2.3).
Number_of_iterations = 2 (int)
Number of iterations that Bandmerge should use to refine the source positions. For each iteration, the user must also supply a secondary namelist file (see §2.2.2). This cannot be set to zero.
clean_type = 3 (int)
Tells Bandmerge which columns of the input source detection tables to update when running the source position refinement (see §2.2.2). Choices are 1 (update source positions), 2 (update source position uncertainties) and 3 (update both source positions and uncertainties).
s2c_prefix = ‘cnv’ (string)
Sets the prefix to be added to the filenames after converting the positions from RA and Dec to Cartesian X,Y. Normally the user has no reason to change this.
OUTPUT_DIR = <output dir> (string)
Sets the name of the output directory.
OUTPUT_FILE_NAME = <name for output merged source table> (string)
Sets the name of the final output merged source table. Intermediate iteration output tables are given the prefix “iter1_”, “iter2_” etc. This file is written to the output directory.
3.2 Module Parameter Block
The Module Parameter Block contains all of the variables for input into the Bandmerging algorithm. The block is delineated by the following lines:
&BANDMERGEIN
&END
See Appendix A for examples. Most users will find that the default values for the module are satisfactory for their needs. Input parameters are as follows, given in alphabetical order:
Minimum values allowed for the denominator in chi-square and pseudo-chi-square calculations (see §1.6).
Chi_Sq_Max (float, default 36.0, optional)
Maximum allowed chi-square value used to specify the match threshold (see §1.6).
Dump (int, default 0, optional)
Produce optional dump output. Options are Dump = 0 (no additional output - default); Dump = 1 (basic output); Dump = 2 (expanded output; Spitzer data only). If non-zero, the namelist parameter Output_DUMP_Filename_Base must be specified.
Epsilon (double, default 1.0e-12, optional)
Minimum value allowed for determinant in calculation of the inverse of the covariance matrix (used in Position Refinement – see §1.7).
Input_Table_Column<i> = <column name> (string, <i> = 1-32, default is no optional columns, optional)
Allows the inclusion of extra columns from the input file to be copied verbatim to the bandmerged output file (e.g. if you want to include SNR in the output). <i> is a number running from 1-32 that controls the order in which the optional columns are written to the output file. <column name> is the name of the column header in the input file that you wish to include, and must be specified in single quotes, e.g. Input_Table_Column1 = ‘SNR’ will write the SNR column from the input file into the output file in the first column after all of the standard outputs.
LR_Scale_Fac (float, default 1.5, optional)
Scale factor used during Linkage Rejection Processing (§1.6.4) to calculate the looser threshold to be applied to bandpair matching. The new threshold is calculated by multiplying the original match threshold (either Chi_Sq_Max or Pseudo_Chi_Sq_Max) by this scale factor.
NL_print (switch, default 0, optional)
Switch indicating whether (= 1) or not (= 0) the contents of the namelist file should be printed to stdout.
Output_DUMP_Filename_Base (string, default is no dump file, optional)
Base of the output dump file (see Chapter 4). The suffix #.tbl (where # is the band number) will be added to the base filename. If Dump is non-zero then this parameter must be set.
Output SPCMB_Filename (string, required)
Name of the (QA) spectral combination counts output file (see §4.2).
Output_STAT_Filename (string, required)
Name of the output statistical summary table (see §1.8 and §4.3).
Pseudo_Chi_Sq_Max (float, default 36.0, optional)
Merge threshold used in confusion processing (see §1.6.4).
SigMin (double, units arcsec, default 0.03, optional)
Minimum sigma value allowed in position calculations (see §1.7).
Signal-to-noise ratio threshold for input band <n> used in statistical summary computations (see §1.8; Spitzer data only).
Status_Check_Flag (integer, default 0, optional)
May be set to 0, 1 or 2. Any other values will be ignored and a WARNING message will be printed. See Appendix B for details on status flags.
Status_Threshold (integer, default 0, optional)
May be set to 0 through 6. Any other values will be ignored and a WARNING message will be printed. See Appendix B for details on status flags.
Trace_PS<n> (int, <n> = 1-7, default 0, optional)
Source identification for a point source in input band <n> that should be traced through the processing. A value of 0 or the absence of this keyword indicates that no source should be traced in this band. This functionality has not been implemented, and so users should set this option to 0.
Warning_Max (integer, default 10, optional)
Maximum number of warnings that may be printed regarding divisions by zero, negative square roots, and/or negative (pseudo-) chi-square calculations found.
X_Window (float, units arcsec, default 10.0, optional)
Coarse window for search in X direction for merge Candidates (see §1.6.1)
Y_Window (float, units arcsec, default 10.0, optional)
Coarse window for search in Y direction for merge Candidates (see §1.6.1)
