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Ax Per Temperature estimation

Posted: Sun Nov 02, 2014 7:01 pm
by Jacques Montier
Hello all,

My purpose is to get temperature of the Ax Per hot component.
So i start from Ax Per spectrum
20141031_axper.png
20141031_axper.png (7.12 KiB) Viewed 4973 times
Then i substract the continuum
20141031_axper_continuum_off.png
20141031_axper_continuum_off.png (6.42 KiB) Viewed 4973 times
I found the colour exces E(B-V) = 0.27
http://www.astronomie-amateur.fr/feuill ... AXPer.html

I could deredden the spectrum with the Isis dereddening tool
20141031_axper_continuum_off_dereddened.png
20141031_axper_continuum_off_dereddened.png (7.32 KiB) Viewed 4973 times
The i could measure relative flux of HeI HeII and Hbeta lines with Fityk.

HeI : 4471A -> 18.71
HeII : 4686A -> 206.55
Hbeta : 4861A -> 524.13

Temperature can be computed by the formulas found on François's web site
http://www.astronomie-amateur.fr/feuill ... Cyg_2.html
http://articles.adsabs.harvard.edu/full ... .116..210I Iijima, T. 1982 p 214

T [K] = 10000*(19.37 * racine(K) + 5.13)
with K = 2.22 * F(HeII 4686)/(4.16 * F(Hb 4861) + 9.94 * F(He I 4471))

I found the temperature value : 136567 K ~ 136600 K.

Do you think that the method and value are correct ?

Thanks a lot for your advices

Best regards,

Re: Ax Per Temperature estimation

Posted: Mon Nov 03, 2014 6:28 pm
by Francois Teyssier
Bonsoir Jacques,
Cela parait trés correct
C'est l'ordre de grandeur des composants chauds dans les symbiotiques (combustion permanente de l'hydrogène provenant de l'étoile géante)

Murset (1991) donne T* = 105 000 K (mesure 1984)
Mikolajewska (1922) donne T* = 125000 K et 145000 K pour les périodes 1981-1982 et 1983-1986

Ce serait intéressant de faire les mesures sur les spectres depuis août

François