Overview
These Python scripts process WiFes datacubes into kinematic maps and line indices. All of them require python, and python packages - pyfits, scipy, pylab, to be installed on your computer. The two main scripts are; kinmap.py and abswidth.py doing the processing and map plotting. The additional spectrum.py and plot.py are useful for plotting already processed arrays and improving map resolution. All scripts should be run from the same directory as the data they are processing is saved in. Alternatively, the entire file path must be specified.
Creating kinematic maps - kinmap.py
Kinmap is used to make kinematic maps of galaxies. Its input are the raw .fits datacube, and a .fits template - needed for cross-correlation. Inputs must inlcude the '.fits' extension.
It produces 4 outputs:
- Array and plot of redshifts
- Array and plot of peak cross correlation FWHMs
- Array and plot of brightness counts in each spexel
- Cosmic-ray processed datacube
All the outputs are saved in a folder in the directory of the script. Initial datacube cutoff should be set high(~1000). The final brightness plot is a good indicator of where the nucleus is. The hottest nucleus spexel(s) should be plotted using spectrum.py, in order to decide on the cosmic ray cutoff. In this example, spexels (15,15) and (16,15) should be plotted(row,col). The template cutoff can be chosen using the plot created before prompting for it.
After processing is finished, histograms of redshift and FWHM values are displayed, which are to be used to determine the upper and lower limits of final plots.
Absorption line depths - abswidth.py
This script creates a map of absorption line depths, 1 being low depth, 0 being high depth. Its inputs are the (cosmic-ray processed)datacube and its redshift array, both previously produced by kinmap.py. Its output is a map of absorption line widths. After selecting the required arrays, user has a choice of selecting the absorption line depth, for which the map is needed. Upper and lower limits of the final map are determined using a histogram.
Individual spectrum plotts and array plots - spectrum.py and plot.py
These are small programs for easy plots of processed data. Spectrum.py plots a spectrum of an i-th row, j-th column, of the unprocessed datacube and is intended for CR cutoff selection. Plotting (16,15) spectrum from the example above, we see the cutoff is at ~700 counts. Plot.py is used to plot any of the .npy arrays produced by kinmap.py, in case user wants to change the upper/lower limits chosen before. Plots must be saved manually.
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