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Aha... Not quite as expected!

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Anthony Rodda's picture
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Joined: 01/09/2014 - 14:15
Aha... Not quite as expected!

So far so good.  I've produced circa 30+ spectra of Miles stars, running comparisons and getting good fits and flux calibration.

Just verging on the confidence necessary to chase science targets when this happens...  

ISIS without instrument response correction - but unlike anything I've seen.  

I'm sure someone will recognise the deliberate error so please wade in.  I've probably not centred the star in the slit and so registered a disproportionate amount red band or captured a monumental amount of CA.

Regards

T

Anthony Rodda's picture
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ignore this bit... finger trouble.....

Just realised it's a double star aka *132 Tau! Any chance it's 'real'?

Regards

T

John Simpson's picture
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132 Tau

Not sure if this helps or not, maybe just typo but your chart shows HD222368 [which is Miles listed in ISIS], but 132 Tau is HD 38751[also Miles listed] and quite some distance away?

Regards

john s

Robin Leadbeater's picture
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The spectrum features do look

The spectrum features do look more F7 (HD222368) than G8 (HD 38751)

Robin

Robin Leadbeater's picture
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Saturation ?

Hi Tony,

A couple of ideas:-

It looks like there is a huge hole in the spectrum from ~4500-6600 where the response should be highest. Could there be saturation in these regions ?

Alternatively could you have set the binning zone limits very narrow or offset from the middle of the spectrum so it is missing part of the spectrum in the middle wavelengths ?

Cheers

Robin

Anthony Rodda's picture
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Thanks Robin

I'll check both.

Regards

T