Zet Tau evolutions

Information about outbursts of eruptive stars, Be activity, ...
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Valerie Desnoux
Posts: 97
Joined: Wed Sep 28, 2011 4:52 am

Zet Tau evolutions

Post by Valerie Desnoux »

Looking at latest spectra from zet Tau, it shall be noted that the H-alpha profile is evolving in few weeks. Zet Tau is a binary star, always evolving, but this is always interesting to follow... Hope Ernst will bring us lights on this episode.
bess_zettau_20111228.png
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Valerie
Ernst Pollmann
Posts: 461
Joined: Mon Sep 26, 2011 7:16 pm

Re: Zet Tau evolutions

Post by Ernst Pollmann »

Hi Valerie,
are you sure, that your 2011-12-28-spectrum is really OK ?
My spectrum, only few days later, does show, that the V peak contains a triple-peak component and has the same hight as the the R-peak. I took it with the 2400 L/mm grating.

The appearance of the triple peak component is still a mystic sign. But Thomas Rivinius wrote me last year, that a triple peak component will appear only in a certain phase of the orbit of the companion.

Hopefully we have the chance (because of the weather), to continue this interesting evolution.

Best wishes, Ernst
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Active Spectroscopy in Astronomy
http://www.astrospectroscopy.de
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Halpha zeta Tau.jpg
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Ernst Pollmann
Posts: 461
Joined: Mon Sep 26, 2011 7:16 pm

Re: Zet Tau evolutions

Post by Ernst Pollmann »

Hi Valerie,
Halpha profile changes are observable obviously all the time. Sometimes the third (triple) component is within the V-peak, little later within the R-Peak and vice versa.

Look at the attached profile monitoring.
The time base seems to be fairly short (few weeks). Possibly this is caused by the small mass (or) diameter of the disk.
Remember: the Halpha-EW is on a historical small level right now.

Ernst Pollmann
----------------------------------------
Active Spectroscopy in Astronomy
http://www.astrospectroscopy.de
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zeta Tau.jpg
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Ernst Pollmann
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Re: Zet Tau evolutions

Post by Ernst Pollmann »

The decrease of emitting envelope should lead to termination of pronounced long term variations.The pronounced V/R variations have stopped with decrease of emission. As one can see in the V/R plot, expected maximum at the end of the plot seems to be missing (see attached figures).
Further observations are important for confirming this interesting development phase.

Ernst Pollmann
----------------------------------------
Active Spectroscopy in Astronomy
http://www.astrospectroscopy.de
http://www.astronomie.de/astronomische- ... troskopie/
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VtoR.jpg
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EW.jpg
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