Now that I have a table of NUV
data from GALEX (courtesy of our new undergrad - Billy!), we can start making some color cuts to determine some sort of "youngness" parameter. In David's paper (Rodriguez et al. 2011), he plotted NUV-J vs J-K and made color cuts from Findeisen & Hillenbrand 2010. Here I've plotted our M stars on the same scale so we can see where they would lie on David's plot:
The purple/blue cloud in David's plot represents galaxies. What I'd really like is Figure 3 from david's plot, but scaled with stellar age. I'm going to add some of the stars from his paper which do have ages on this plot and see where the DEBRIS M stars lie.
Another option would be to simply track down a sample of M stars with published ages which have been observed with GALEX.
You probably saw Figure 4 in my own paper, which is similar to the Figure 3 you have here, but zoomed in to the region of interest and color-coded by age.
ReplyDeleteA problem with this method is flare stars- these can be old but have the same NUV colors as younger stars. Also, this method may not be too useful beyond ~100-300 Myr. I suppose it doesn't hurt to try it out, though.
I can point you to Findeisen et al. 2011 Figure 8 and 9 for some plots of NUV colors vs age, and Shkolnik et al. 2010 Figure 6 for age diagnostics of M stars.
PS: I would suggest double-checking your Galex-DEBRIS matching. An M-star shouldn't have J-K=0, and the one with NUV-J~0 is also suspicious.
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