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Fourier Spectra

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Ariella
Fourier Spectra

Hello!

I am looking to do fourier analysis to produce a fourier spectra of the variable star XX Cyg. I am using VStar and after inputting my string of Magnitude VS. HJD - it is not showing me that the fundemental frequency for XX Cyg ( ~  7.5 ) is going to the main power.

Has anyone worked with this or tried to do something similar ?? Not sure if I am inputting anything wrong or not reading it right. 

 

Cheers

David Benn
David Benn's picture
DCDFT parameters

Hi Ariella

I downloaded the last two years of XX Cyg data in VStar and used these parameters in DCDFT with Period Range:

minimum: 0.1

maximum: 0.2

resolution: 0.000001

The top hit from this is 0.134864 days which is close to the VSX period:

  https://www.aavso.org/vsx/index.php?view=detail.top&oid=10969

That gives a reasonable phase plot.

You mention 7.5 for the period, so perhaps we're talking about a different star.

David

Ariella
Thank you!

I was able to finish my research- thank you for your help

SFS
Period vs Frequency

Perhaps by 7.5 was meant the nominal frequency (in the conventional-only-in-astronomy cycles per day).  A common, minor error.

David Benn
David Benn's picture
Period vs Frequency

Of course! Thanks.

David

Ariella
Parameter

I was sucessfuly able to get the value I needed - I noticed while changing the paramters ( min max and resolution ) the main frequency stayed the same but depending on how the parameters were changed - majority of other numbers changed. Also, the order of power ( which should be the primary frequency in my research ) changed. Are the parameters extra sensitive to certain values or inputs? Or do they mean something special and I'm missing it?

Sorry for the questions - I am just an undergrad trying to figure this out! Thank you

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