Hi Noel,

What slit width did you use? Did you measure the resolution? (The FWHM of the neon lines). I suspect that the resolution is well short of the 1A specified for this project. An 1800 line grating with a 50um slit width like Lothar is proposing with his C14 might give a good result with a 20 inch aperture though, provided your seeing is good (What is your typical star FWHM at your observatory?)

Cheers
Robin

----- Original Message -----
From: Noel Richardson ([email]fg-spek-convento(==>)vds-astro.de[/email])
To: fg-spek-convento(==>)vds-astro.de ([email]fg-spek-convento(==>)vds-astro.de[/email])
Sent: Tuesday, December 13, 2011 9:34 PM
Subject: [fg-spek] Re: New ProAm campaign in 2013



We have a new LHIRES III spectrograph at our observatory. This summer, we obtained spectra of 3 WR stars (136, 137, and 140) with a 600 g/mm grating and an SBIG ST-8 camera. The dispersion (in the red) was ~0.75A/pix and the spectra are shown below. These were obtained with the instrument on a 20-in, f/8 telescope. Exposure times are given in the figure. These are not an ideal set-up for this campaign, but are good test exposures.

I would be willing to share these files with people that were interested in seeing the data quality during these initial planning steps.

I will also post another idea I had about using Hubble.

----- Original Message -----
From: Andrenicolas Chene (fg-spek-convento@vds-astro.de)
To: fg-spek-convento@vds-astro.de (fg-spek-convento@vds-astro.de)
Sent: Wednesday, December 14, 2011 12:42 AM
Subject: [fg-spek] Re: New ProAm campaign in 2013


A 1.5 magnitudes difference is a factor ~4 in flux (hence a factor 2 in S/N). If you could reach a S/N of 200 in one hour with WR140, you will reach a S/N of ~100 for WR134,5,7 with the same exposure time.



Berthold Stober wrote: hi AN,

as said, I never tried to observe such stars of 8 mag or even weaker. You can find a lot of spectra I made in the past in the database in our forum, there are some spectra from WR 140, this was the weekest star I explored systematically......)

cheers berthold




André-Nicolas Chené
Postdoctorado
Universidad de Concepcion
Universidad de Valparaiso

----- Original Message -----
From: Andrenicolas Chene (fg-spek-convento@vds-astro.de)
To: fg-spek-convento@vds-astro.de (fg-spek-convento@vds-astro.de)
Sent: Tuesday, December 13, 2011 1:52 PM
Subject: [fg-spek] Re: New ProAm campaign in 2013


I also agree with Tony... But I don't think we need to observe WR137 during the whole run. Neither WR135... Only WR134 would really benefit from a very long time span. So, why don't we do the following:

We observe WR134 as the prime target. Then, for a good fraction of the time, we also observe WR135, mostly trying to do a 24/24h coverage, which has never been achieved yet. Then, for a shorter amount of time (1-2 weeks), we can change WR135 for WR137. This would be somehow useful AND give us a nice story to tell Sky and Telescope.

Before organizing the schedule, we would first need to know how many observers+telescopes are involved, what are the capacities of all those spectrographs (resolution, Exp. Time required to reach S/N=100-200, wavelength coverage) before we decide who observes what star, what line and when.

AN

Thomas Eversberg wrote: Hi Teggoneggy!

That's a good argument (your arguments are far to often very good... ) and I can support it. Maybe my expectations are too high. It would be great to establish a REALLY large group being able to cover even WR 137. Perhaps we have the luck to welcome our highly active french friends to the team.

I suggest, we leave this open for a while and I add André-Nicolas' science case for WR 137 to the website with a specific remark that it is considered as a back-up target. What do you think?

Oh, I just see that Noel Richardson from Atlanda registered (Hi Noel). I invited him and Doug Gies to have a look on our discussion. Noel has already some nice ideas...

Cherio, Tomanaggo

PS: 1867 might be the birth of Canada but more important it is 2177 in the Babylonian Seleukidik era (whatever that is).



--------------------------
André-Nicolas Chené
Postdoctorado
Universidad de Concepcion
Universidad de Valparaiso

Hi AN et al.:

My gut feeling tells me, though, that if we monitor any of these stars, then better to do it "all or nothing",
i.e. intensely during the whole 4 months, rather than part of the time. This applies to whether we want to monitor CIRs and their long-term stability (WR134, 137) or constraining the statistics of clumps (WR135). Observing WR135 for only a few nights (or even a week or two) would probably not go much beyond the already intense 3-day run using WHT/CFHT in 1994 (Lepine et al. 2000). And that short run does not address the question of the long-term behaviour of wind clumps.

Best, Tony

----- Original Message -----
From: Andrenicolas Chene (fg-spek-convento@vds-astro.de)
To: fg-spek-convento@vds-astro.de (fg-spek-convento@vds-astro.de)
Sent: Wednesday, December 14, 2011 12:39 PM
Subject: [fg-spek] Re: New ProAm campaign in 2013


Well... when I want less targets, you want more, and when I want more, you want less...

Ok... What if we plan the first 3.5 months for WR134+WR135, and, like I said, we keep the last 2 weeks for WR134+WR137. 3.5 months for WR135 is significantly larger than 3 nights, right? Also, for WR137, all we need is to cover a few times the putative 0.8d-period, and to compare what we get with observations obtained during the last 6-7 years in order to verify if any changes in the period are seen at different orbital phases of the binary.

I think whether we do WR134 OR WR134+135+137:

WR134: With 4-5 spectra per night, we can monitor adequately the line profile variations, while 2-3 spectra would be a bit more challenging. Hence, the more spectra we get for that star, the better. If we also observe WR135, will we still have good results for WR134 AND get something good for WR135?

WR134+135+137: If you can convince me that we can share nights with two targets, why should it be only WR135? For just the cost of a fraction of the campaign, we add a third target. It is true that the science case I have in mind doesn't absolutely need the intensive effort the Pro-Am campaign allows. On the other hand, a few spectra would be useful and studying the three first WR ever discovered is a good story for media. "On the traces of Charles Wolf and Georges Rayet". Sounds cool, no?

What do you think?

Saludos

Tony Moffat wrote: Hi AN et al.:

My gut feeling tells me, though, that if we monitor any of these stars, then better to do it "all or nothing",
i.e. intensely during the whole 4 months, rather than part of the time. This applies to whether we want to monitor CIRs and their long-term stability (WR134, 137) or constraining the statistics of clumps (WR135). Observing WR135 for only a few nights (or even a week or two) would probably not go much beyond the already intense 3-day run using WHT/CFHT in 1994 (Lepine et al. 2000). And that short run does not address the question of the long-term behaviour of wind clumps.

Best, Tony





André-Nicolas Chené
Postdoctorado
Universidad de Concepcion
Universidad de Valparaiso