Examples of XRBID Functions

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Examples of XRBID Functions#

Throughout this guide, I’ve included several examples of how to use the functions accessible through XRBID. Here, I compile more examples of the functions in XRBID and how they may be used, especially those not discussed in the main guide.

Important

This section is under construction!

RunPhots()#

As of version 1.5.0, RunPhots() now takes three aperture radii: min_rad, max_rad, and extended_rad. min_rad corresponds to the aperture radius used to take photometry of a point source (i.e. a star) and should usually remain at 3 pixels, unless a good argument can be made for a better aperture radius for stars in a particular galaxy. max_rad should always remain at 20, since the aperture correction out to infinity is taken from 20 pixels to infinity, unless you know what you’re doing with this code. The new parameter, extended_rad, represents the radius of extended sources. This should be set to the pixel radius of a standard cluster in your galaxy. The default is 10 pixels, as this was a good setting for clusters in M81, but you should always check your own data to see if a smaller or larger aperture radius is better suited to your particular data set.

For M101, which is 2 Mpc farther than M81, I found that clusters are well-constrained by an aperture radius of 8 pixels. Thus, when running RunPhots() for M101, I set extended_rad = 8:

from XRBID.AutoPhots import RunPhots
from astropy.io import fits 

hdu = fits.open("M101_mosaic_acs_f555w_drc_sci.fits")

RunPhots(hdu, gal="M101", instrument="acs", filter="F555W", 
         fwhm_arcs=0.3, num_stars=25, extended_rad=8)
         
hdu = fits.open("M101_mosaic_acs_f814w_drc_sci.fits")

RunPhots(hdu, gal="M101", instrument="acs", filter="F814W", 
         fwhm_arcs=0.3, num_stars=25, extended_rad=8)

hdu = fits.open("testdata/M101_mosaic_acs_f435w_drc_sci.fits")

RunPhots(hdu, gal="M101", instrument="acs", filter="F435W", 
         fwhm_arcs=0.3, num_stars=25, extended_rad=8)
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