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Photometry and Light curves
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You have reach the last step. By running phot.csh
you will build the light curves of each object in the file phot.data.
Good to have a look at the configuration file before running the script.
The configuration file for the photometry is register2/phot_config.
According to the mean size of the PSF in your image you should specify
some approximate value for the radius of the annulus where to estimate
the background (rad1_bg is the inner radius
of the annulus and rad2_bg is
the
outer radius). Two other important parameters are the photometric
radius, or the radius of the circle within which the pixels of the object
will be fitted in order to estimate the flux (rad_phot),
and the radius for the flux normalization (rad_aper).
Then run the light curve builder:
./phot.csh
Five light curve
will be created, they are named lc*.data (they are in the image directory,
images2) Have a look at lc0.data for instance. You look for a period in
the light curve by using the C implementation of Schwarzenberg-czerny method
provided in the package. For instance, try ../bin/czerny
-i lc0.data -a 0.2 -n 1. The routine should
return a period very close to 0.5 days. You can view the light curve by
plotting the file lc.data. The first 2 columns contains the phase and the
corresponding flux.
You can do the same for the other light curves, the remaining periods
should be:
0.25, 2.1, 0.75, and 3.5 days.
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