Globular cluster star-vation: Lost 99% of its mass?

[Ann]

Back to the Future: Estimating Initial Globular Cluster
Masses from their Present Day Stellar Mass Functions

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M12. NASA, STScl, ESA

A recent study of globular clusters claims that because globular clusters lose their low-mass stars at a much higher rate than their high-mass ones, the apparent shortage of low-mass stars in any present-day globular cluster gives us a reasonably good idea of its initial mass.

Jeremy J. Webb and Nathan W. C. Leigh wrote:
Figure 4 suggests that the clusters in our data set were on average a factor of 10 times more massive than they are today, with some clusters having initial masses greater than a factor of 20 times (e.g. NGC 5286 and NGC 6362) or even 100 times (e.g. NGC 6218) larger than their present day values.

Wikipedia wrote about NGC 6218 (also known as M12).
A study published in 2006 concluded that this cluster has an unusually low number of low mass stars. The authors surmise that they were stripped from the cluster by the gravitational influence of the Milky Way.

This suggests that globular cluster M12 would initially have had a mass of more than ten million solar masses, whereas today its mass is closer to "only" 100,000 solar masses. So M12 would have been 100 times more massive than today when it was it was newborn.

Ann

[bystander]

ESA/HEIC: The Riddle of the Missing Stars
STScI/NASA: Hubble Catches a Stellar Exodus in Action