WR140 periastron campaign 2008-2009
This campaign may be the first great ProAm international effort. It embodies professional and amateur astronomers of 8 nationalities, both European and American. Satellites Swift and RXTE are engaged as well. Besides the intense coverage of the WR140 system, other hot massive stars are being measured, stars of the spectral types Be and Oe. Only nine of the last type are known. A detailed description of this campaign can be found at this link and for images of our mission, view the Blog (in Portuguese).
WR140 is a binary system composed by a Wolf-Rayet WC7 star and a massive main sequence O4-5 star. Its orbit is highly eccentric (>0.8), and its period is about 7.9 years. This periastron took place the 12th January 2009. The measurements aim the assessment of the stellar winds interactions before, during and after the periastron. The system belongs to a group of systems known as Wind Colliding Binary Systems.
The figure shows the spectra of the binary system captured before (red) and immediately before (Blue) the periastron. The spectra reveal broad emission lines due to the dynamics of the WR star. The collision of the stellar winds will act mainly on the CIII and HeI lines. In the figure, an increase of the amplitude in the CIII line is evident. The Natrium absorption lines don't belong to the system, being due to the inter-stellar medium. They are used as reference point for the Doppler measurements on the lines affected by the wind collisions.
The spectra in the figure were captured in the Fronteira observatory (2008) and in the Army's Geographic Institute observatory (2009).
Resulting papers:
http://adsabs.harvard.edu/abs/2015arXiv150101377R
http://adsabs.harvard.edu/abs/2012ASPC..465..372F
http://adsabs.harvard.edu/abs/2011MNRAS.418....2F
http://adsabs.harvard.edu/abs/2011IAUS..272..501F
http://adsabs.harvard.edu/abs/2011IAUS..272..414M
http://adsabs.harvard.edu/abs/2011BSRSL..80..668F
http://adsabs.harvard.edu/abs/2011BSRSL..80..170M
http://adsabs.harvard.edu/abs/2011arXiv1101.1430F
http://adsabs.harvard.edu/abs/2015A&A...575A..99R