In order figure out the mass of the stars, I have to fit it to theoretical curves for a range of stellar masses at the same age and metallicity as the cluster.
The website CMD computes all the relevant data for a given age and metallicity, and can also factor in extinction, circumstellar dusk, and returns a file filled with data points over a range of masses. In this file are the Absolute Blue B and Visual V Magnitudes.
The WEBDA database has data on each star for a given open cluster. In this I can get the relative B and V magnitudes.
So as just a rough start, I tried plotting (B-V versus V)several clusters (translated to absolute magnitudes by compensating for distance) and roughly same age isochrones in Matlab. I plotted -V actually instead of V so that the graph would look right side up. It didn't work.
I fiddled around with it for a while to try and figure out what was wrong. The sun's data point fell into the cluster data, so I knew the isochrones were wrong. Finally I discovered that when importing the data files, Matlab stuck a column on Nan in front of the rest of the data. I was thinking B and V were in 9 and 10 respectively, but they were actually shifted and in 10 and 11th columns.
NOW IT WORKS YAY!!!!!!
Excellent job ISOlating the ISOchrones as the error source! That's a mighty-fine looking H-R diagram there.
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