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A first look at the targets with the Star Analyser

Posted: Sun Dec 09, 2012 1:49 am
by Robin Leadbeater
The attached document (zipped pdf) describes the first look at the T Tauri stars using a Star Analyser. The idea is to develop a method for users who have not used the Star Analyser for serious work before.

A start, but very much "a work in progress" :?

Cheers
Robin

Re: A first look at the targets with the Star Analyser

Posted: Sun Dec 09, 2012 1:49 pm
by Andrew Smith
Nice start Robin.

Have you given up on using the requested comparison star or have the researchers accepted the use of other reference stars?

It was not clear to me if they want raw or corrected spectra of the target and reference stars or just target stars corrected by an acceptable reference. What do you think?

Regards Andrew

Re: A first look at the targets with the Star Analyser

Posted: Sun Dec 09, 2012 4:23 pm
by Robin Leadbeater
Hi Andrew,

For the slit spectroscopy, I think it was agreed by the PI that brighter comp stars than those originally suggested would be better but I am not sure if any were decided on. (Christian/Francois?) The main requirement for the comp stars is that they are stable and preferably hot (few lines)

For the Star Analyser, the aim is still to have comp stars in the same field if possible, most likely the ones shown in the DSS fields published above (These would not be the same as the slit spectrograph comp stars but could be cross checked against them)

The minimum data products would be dark, flat, background corrected, binned and wavelength calibrated spectra of the targets and traceable comp stars taken close to the same time and elevation. The instrument response/atmospheric corrections can then either be done by us or the PI.

At some stage cross checks between the various comp stars would be needed but these could be done at leisure, ether by us or by the PI using for example the Liverpool telescope

Cheers
Robin

Re: A first look at the targets with the Star Analyser

Posted: Sun Dec 09, 2012 9:37 pm
by Francois Teyssier
Hi Andrew (and Robin !)

About reference star, it's clear that we nead a brighter star than those proposed by Darryl Sergisson. Darryl agree.
We have to take more spectra from several observers in order to build a common protocol, noticely reference(s) star(s)
For my last acquisition, I used HR1490, a AV2, mag V 5.2
I have some difference in tne continuum shape with Christian's ones.
More spectra are needed to fix the protocol (throught a discission bretween the different obversers) and propose it to Derryl Sergisson

Waiting for your spectra,

Best regards

François

Re: A first look at the targets with the Star Analyser

Posted: Sun Dec 09, 2012 11:20 pm
by Robin Leadbeater
Hi Francois,

This evening I am concentrating on DN Tau. I recorded HR 1490 (HD29646) before and after DN Tau and I also have another A star (HD28975) in the same Star Analyser field as DN Tau so I should be able to make a simultaneous response/atmospheric correction and directly relate it to your result using HR 1490.

Cheers
Robin

Re: A first look at the targets with the Star Analyser

Posted: Mon Dec 10, 2012 12:04 am
by Terry Bohlsen
I have only taken on spectra so far for this of DR Tau. I used a relatively nearby reference star at a very similar airmass. This will be different for me compared to you guys in the north so there will need to be a selection of reference stars.
Terry

Re: A first look at the targets with the Star Analyser

Posted: Mon Dec 10, 2012 9:29 am
by Andrew Smith
Francois Teyssier wrote:Hi Andrew (and Robin !)

About reference star, it's clear that we nead a brighter star than those proposed by Darryl Sergisson. Darryl agree.
We have to take more spectra from several observers in order to build a common protocol, noticely reference(s) star(s)
For my last acquisition, I used HR1490, a AV2, mag V 5.2
I have some difference in tne continuum shape with Christian's ones.
More spectra are needed to fix the protocol (throught a discission bretween the different obversers) and propose it to Derryl Sergisson

Waiting for your spectra,

Best regards

François
Thanks for the update François, I am sorry not to have posted any spectra yet but I am still trying to develop an accurate and robust approach to both gathering the data and processing it. I am new to this and, as you may have noticed under my post on A Stars, having some difficulty. Last night I did manage to get some new spectra of bright A stars and seem to have removed the distortion by ensuring the camera lens to CCD distance is as close as I can get it to the optimal value as stated in the LISA manual.

Regards Andrew

Re: A first look at the targets with the Star Analyser

Posted: Mon Dec 10, 2012 6:05 pm
by Francois Teyssier
No problem Andrew,
Working on a collaborative wok is the best way to learn and improve acquisition and treatement methods (especially if Christain is in the game ;)
Best regards
François