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Robin Leadbeater's picture
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Joined: 05/03/2014 - 00:50
Grey ?

I Iooked at this but their claim that the extinction is grey is not the case here if one looks at the photometry in the IR where there was no reduction in H J bands and a smaller drop in R compared with B,V  which is also seen in spectra. Perhaps this can be explained by the large grained dust model but I am surprised they have not considered the available photometry data

andrew.j.smith1905's picture
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Yes somewhat strange

Strange indeed Robin, and suprising as the are both experts on red supergiants. Indeed EML has written a book on the astrophysics of Red Giants!

Maybe the IR bands are more sensitive to Teff than in the V . I will look at her book and see if I can find any comment on it.It will be interesting to see how the discussion develops.

Regards Andrew 

Robin Leadbeater's picture
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beyond 6700A

I see their spectra stop at 6700A before the larger changes in the spectrum become obvious

andrew.j.smith1905's picture
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Nice discription

In any event I found their discription of how the did the Spectrophotometry interesting.

Regards Andrew 

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