Observation request: T Tau early in January

[Robin Leadbeater]

Is anyone else seeing evidence of the emission in the spectrum extending beyond the star (seen here above the stellar spectrum) or is it some aberration in my system

Robin

EDIT: It appears to be genuine nebulosity in emission as it inverts after a meridian flip

[Paolo Berardi]

Hi Robin, this is my stretched 2d spectrum (after combining 2 jan frames) taken through a C9.25 f/10 telescope. I have very faint "smears" in correspondence with the emissions. I happened to see them (visible on both sides of spectrum axis) in other faint target spectra but I thought they were caused by star oscillation along the slit axis during the exposure (bad seeing, too faint guide star image).



Paolo

[Paolo Berardi]

I realize that my spectrum seems wider (in Y direction) and telescope focal length is lower respect to your setup, so the lines may be hidden.

That could be very interesting!

Paolo

[Robin Leadbeater]

Hi Paolo,

Perhaps it is localised in a particular direction. In which direction does your slit run (mine runs in north-south) ?

After two bad nights here, conditions tonight are of course perfect and I have been running continuously for 7 hours now at 5 min cadence. A pity it is a day too late

Robin

EDIT: It seems the emission nebula surrounding T Tau is well documented eg
http://adsabs.harvard.edu/abs/1950ApJ...111...11H

[Terry Bohlsen]

I took a series of relative short exposures of this star last night before I was clouded out using my LISA at R=1500 aprox.
What do I do with the fit files. Is there someone I need to send them to?

Terry

[Paolo Berardi]

Hi Robin, thank you for info! That is very interesting! So there is an irregular nebula that begin from T Tau and extend several arcseconds. My slit axis has ~ 90 degree position angle (E-W direction), so it could be another problem to see nebula spectrum.

Very nice spectrum Terry, congratulations. I'm waiting for the same your question...

Paolo

[Francois Teyssier]

Christian will create an ARAS page
You can send him the spectra and a copy to me for the data base

Data Base : http://www.astrosurf.com/aras/Aras_Data ... u/TTau.htm
with low res spectra from Peter

François

[Christian Buil]

Dear Hans,

I have important questions about the T Tau call for observation.

Other Chandra observations on this object are programmed? Do you think it is useful to intensively observe this star now?

Observers of the stars are quite numerous, others may participate (but weather is the most important problem). It seems that we can get good measurements of equivalent width with good temporal resolution also (we noted the time resolution needed, 10-15 minutes) and also fine profile evolutions.

I find interest to launch a coordinated operation on 4-5 nights outside the Chandra program, focusing maximum observer (and observations).
The results could be of some interest (flare detection with cross confirmation, instruments comparison, ...). This could be also a preparation for other campaigns.

Do you encourage this initiative ? It appears correct? Can you help for analyze the (potentials) results?

We can open a specific database on ARAS web site for centralize results and coordinate.

Christian

[Robin Leadbeater]

An animation of 8 hours of continuous observation at R ~5500 and 5 min cadence from 3rd Jan and a plot of the EW. There is some variation, though the lowest EW point coincides with a period of lower SNR due to thin cloud.

Robin

@_t_tau_20150103_interp.gif (493 KiB) Viewed 18831 times

ttau_Ha_EW_SNR_20150103.png (13.88 KiB) Viewed 18831 times

[Francois Teyssier]

Data Base updated with spectra from Peter, Paolo and Terry

http://www.astrosurf.com/aras/Aras_Data ... u/TTau.htm

"TTauri" isn't "Ttauri" : thanks Paolo !



François