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Statstar Exercise Update, Version 2

Oops, I read the wrong column in the table for the M=0.5M_sun, X=0.7 and Z=0.008 star: the correct luminosity is 0.021300L_sun, and effective temperature is 2321.40 K. The data for the X=0.7 and Z=0.01 star seems to be correct, at least it ran OK for me. --Dr. A

Further Update! While the above values are the ones given by the textbook authors for that mass and metallicity, when I ran them I found to my amusement that they are close but not quite correct. What a wacky sense of humor those guys have! I hunted around a bit, but after 2 or 3 minutes, couldn't fine tune the values to get an exact solution, and thus decided that it was impossible to do so ;). So... lets try this with 0.6M_sun stars instead of the 0.5M_sun stars (yes, I've tested these values and they work!). For the X=0.7, Z=0.008 star, L=0.05692 L_sun, and T = 2910.8 K, and for X=0.7, Z=0.01, L = 0.0486 L_sun, and T = 2760.04 K. Sorry for the inconvenience. -- Dr. A

Gnuplot Information

Gnuplot is a free, fairly simple to use stand alone plotting package available for several operating systems including Linux and Winders. Gnuplot also has a rudimentary set of built in analysis tools including a large function library and non-linear fitting.

A gentle introduction to gnuplot is available on the University of Northern Iowa's College of Natural Sciences Computing Laboratories Introduction to GnuPlot pages.

A short but useful tutorial on using some of Gnuplot's advanced features, including fitting has been written by Henri Galvin at Duke University.

Downloading Statstar

You can download either the fortran code or a winders executable version of statstar from Dr. Pinsky's web page, or from the textbook author's web site.

Statstar Plotting Script

The script statstar.plot can be used as a template for plotting statstar output.

The classes statstar results for plotting is in M_T_L_results.dat. The file has been formatted for plotting using gnuplot, and the instructions are inside the file as well.


Send Dr. Andersen email: vandersen@uh.edu