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I'm trying to see how to calculate rotation curves for a spiral galaxy.

The data I have is brightness profile (mag/arcsec^2) and observed rotation curve - to see how it fits.

from what I found I need the total mass, and for that I need the surface mass density.

I couldn't find how to convert the brightness profile to mass density.

I can probably let matlab integrate the spline of the brightness profile, but that's not the mass density, so it wouldn't give me the mass I need.

Would appreciate help.

References to books (preferably with solved exercises) or other material are very welcome.

zaq

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# Calculating a rotation curve

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