During the 2015 Potsdam conference on Wolf-Rayet stars a small team discussed a new ProAm campaign on WR stars.
The professional team
Team members have been Tony Moffat and Nicole St-Louis (Montreal), Andy Pollock (Sheffield), David Huenemoerder (MIT), Lidia Oskinova (Potsdam) and me. A number of other professionals are also on board. They are i.a. Tomer Shenar (Potsdam), Andre-Nicola Chené (Hawaii), Mike Corcoran (Goddard Spece Flight Center), Gloria Koenigsberger (Mexico) and Stephen Ro (Toronto). Others will certainly join the campaign later.
The goal
As some of you remember, our last WR campaign at Tenerife had been highly successful. Within our data Emily Aldoretta not only could monitor Corotating Interaction Regions (CIR) in the wind but also discovered that CIRs come and go with a period of about 40 days (about 18 cycles of the 2.1 day stellar rotational period). The respective poster can be downloaded at http://www.astro.umontreal.ca/~emily/CA ... er2015.pdf. sThese rotating shock-fronts (see picture) are the only straigth-forward prope for the stellar surface being hidden behind an optically thick stellar wind. From Emily‘s results new questions arise. For instance:
• What is the reason for this interesting long-term behavior? Can it be hot and bright surface spots, resonances in non-radial pulsations or strong but local magnetic fields?
• Do other WR stars show this behaviour?
Please note that these questions can only be addressed with such a long run. For detecting periodic variability of the order of 40 days one can not observe the star for only three weeks. Therefore, such physics are a real domain of amateur spectroscopy at a very good site with excellent long-term weather conditions.
Targets and time
To answer these and other questions we decided to observe four WR stars for a very long time. We will apply for six consecutive months (!) at IAC80 on Tenerife to obtain Echelle spectra of the following WR stars: WR 6 = EZCMa (prime target), WR 22 and WR 24. As additional target we will go again for the periastron passage of WR 140 but now for other lines with the Echelle (see Mons campaign in 2008/09). Because of the location in the sky and WR 140 periastron we focus on the period November 2016 – April 2017.
Except WR 140, all targets are located close to the celestial equator so that our SASER colleagues in the southern hemisphere (New Zealand, Australia, Brazil) could contribute.
Observer teams at Teide and costs
If we really obtain six months at IAC80 we would split the entire run into 12 two-week blocks with maximum two observers. We hence need 24 people who are willing to donate their time for this extraordinary run. As we already have some experience from our last two Teide campaigns we can estimate the costs to be about 1200 Euro each (including flight, rental car, accommodation).
We herewith ask who is interested in this campaign and would probably go to Tenerife for two weeks somewhere in this period. We also ask for support observations from private and professional observatories. They are highly welcome.
The next steps
a) The professionals will soon write a scientific proposal for Tenerife. It is open for discussion who will be the scientific prime investigator (PI) for the different targets and who will reduce the obtaiend data (scientists, PhD or master students).
b) I will be the campaign manager for Teide and the amateurs.
c) I intend to go to Tenerife soon to talk to the local people in charge so that they can see how we manage the run and how we want to avoid potentially upcoming problems with such a big team.
d) In contrast to the last two Teide campaigns this time we will organize a „pre-campaign“ meeting so that every team member is able to learn the most important procedures and to meet other members in person. I will do that to avoid potential misunderstandings with respect to the campaign and specific responsibilities (everybody will pay the same for such a meeting wherever it will be).
Please think about your participation in this extraordinary campaign and please think about going to Tenerife. If you are not sure I recommend to talk to members of the last campaigns. They will certainly confirm that such observations at a professional observatory is a unique experience. By experience, the procedures at the telescope are simple and easy for everybody, even if you are still in a spectroscopic learning process. The discussion is open!
Cheers, Thomas
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