Subject:
MiMeS2 follow up
From:
David Cohen <cohen@astro.swarthmore.edu>
Date:
Mon, 25 May 2009 15:17:40 -0400
To:
Stan Owocki <owocki@bartol.udel.edu>, "Gagne, Marc" <MGagne@wcupa.edu>, Maurice Leutenegger <maurice@milkyway.gsfc.nasa.gov>
CC:
Richard Townsend <townsend@astro.wisc.edu>, Véronique Petit <veronique.petit.1@ulaval.ca>

Hi,

I wanted to share my talk at the Paris MiMeS2 meeting with those of you who couldn't be there.

http://astro.swarthmore.edu/~cohen/presentations/cohen_MiMeS2_may2009.pdf

It's an overview of x-rays and magnetic massive stars, using theta1 Ori C as a template - but then going on to discuss diverse behavior in zeta Ori, sigma Ori E, tau Sco...  Marc and Stan, you'll note my slides #9, 10 in which I lay out the three-mechanisms-but-all-about-shock-heating framework.

Maurice and others, I'd be interested in your feedback on slides #74-76.

Note that there are lots of files in the directory where the talk is that might be useful to you when preparing your own talks.  Feel free to use them (see directories called movies, images, papers).

I don't have a big meeting core dump (a la Stan) to share.  My overall impressions are the following:

Things are going well with the espadons observing; most of the focus has been on the targeted component so far (but there's not yet lots of new information about, say, the topology of the field on theta1 Ori C for us to use in our modeling and multi-wavelength data analysis efforts).

Consequently, there's not a huge amount of new observations from the survey component.  We're not yet close to doing science with a statistically sound sample (to answer questions that we should be able to tackle in a few years, like, is there a correlation between the presence of a field and rotation?).

The members of the group working with the data are doing a great and careful job.  There was discussion of cross-talk - by which linear polarization can be mistaken for circular polarization.  And Veronique, among others, talked about statistical inferences (in a Bayesian context) about field strengths.  My impression is that there's some dissatisfaction with the "black box" nature of some of the relevant software (for doing the LSD analysis, maybe?) and that concern is exacerbated by the relative lack of published documentation.

Weak fields are being found (including a crazy detection - at the 2 sigma level - of a net <1G field on Vega).  VLT/FORS-detected fields are  being followed up on and generally not detected.  There may be hints of fields in stars like EZ CMa, but no sound detection.

Oleg gave a very nice talk on Zeeman Doppler tomography.

I was somewhat disappointed with the two pure theory talks (Stephane Mathis and Jon Braithwaite).  They certainly seem to know what they're talking about, but I wished they'd made more connections to the observations.

Gregg was a little unhappy that many of the four science focus areas seemed to not yet be...fertile.  E.g. we're not saying much about evolution and magnetars.  But he was positive about the point most directly related to our group - the wind field interaction.

Mary gave a talk on the abundance inhomogeneities on sigma Ori E.  Some of the results were too fresh (e.g. there was something wrong with the He patterns she showed).  She did display pretty good command of the data acquisition and some of the analysis.  But she still needs to work on her speaking style and, especially, question-answering.

Veronique gave a nice talk on other aspects of the x-rays, including a brief overview of our Chandra proposal.  Her talk is here:

http://astro.swarthmore.edu/~cohen/projects/mimes/paris2009/VPetit_Mimes2009.pdf

Actually, eventually, all the talks will be here: http://dev-lesia.obspm.fr/MiMeS/index.php/MiMes:Presentations_from_the_MiMeS_2_workshop_in_Paris

If anyone else who was there has other things to add - including you, Veronique, since you've got a different perspective compared to the members of our group, please chime in.

I've got some meeting photos here:

http://astro.swarthmore.edu/~cohen/pix/2009may/meeting.html

David