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Spectral differentiation in EB?

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keving
Spectral differentiation in EB?

Hi there

First, thanks to all the organisers and presenters of the EB webinar - I learned a lot!

As I was listening, I wondered if it is possible to detect changes in the spectrum of an EB if it is comprised of two widely different spectral types? If so, and you track it over a minimum, there should be some interesting dynamics to observe. I do  spectroscopy and have just started to do do the simulatneous photometry so it might be  a nice project...

Thanks

Kevin

 

 

 

 

sah
sah's picture
Spectral differentiation in EB?

I have no experience with spectroscopy but I think this should be possible. I would suggest starting with a deep total eclipse. During totality, the light from the brighter star is completely blocked so the spectrum of the fainter star can be recorded. At maximum, the spectrum of the brighter star will dominate and you should be able to digitally subtract out the spectrum of the fainter star.

 

I few suggested candidates for summer are V342 Aql, W Del, and U Sge. In autumn, ST Per, Z Per, and RW Tau should also work. For all of these stars, the totality lasts an hour or longer so you will have time to record the spectrum at minimum.

 

SAM

I have no experience with spectroscopy but I think this should be possible. I would suggest starting with a deep total eclipse. During totality, the light from the brighter star is completely blocked so the spectrum of the fainter star can be recorded. At maximum, the spectrum of the brighter star will dominate and you should be able to digitally subtract out the spectrum of the fainter star.

 

I few suggested candidates for summer are V342 Aql, W Del, and U Sge. In autumn, ST Per, Z Per, and RW Tau should also work. For all of these stars, the totality lasts an hour or longer so you will have time to record the spectrum at minimum.

 

SAM

keving
V342 Aql

Thanks for suggestions,

I managed to track down an article on V342 Aql. ( Erdem et al. New AStronomy , 2007) which gives the spectra of the two components - A4II+[K0IV] (at least that's how I interpreted this information).

A are  K very distinguishable, so maybe this is a starting  point..

 

Kevin

 

 

Ed Wiley_WEY
Ed Wiley_WEY's picture
Spectral differences

If you use BV or BVI you can get a sense of differences in color by calculating B-V and/or V-I for each data point pair (BV pair, VI pair) during the drop to minimum. Since the B amd V (or V and I) are taken at slightly different times there will not be precision, but you will get an idea of basic color changes, if any.

Ed

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