Astronomy and Astrophysics – Astrophysics
Scientific paper
2005-12-07
Astronomy and Astrophysics
Astrophysics
12 pages, 6 figures (3 colour figures), accepted by A&A (in press)
Scientific paper
10.1051/0004-6361:20042160
We present mid-infrared (2-12 micron) spectra of the microquasar SS 433 obtained with the Infrared Space Observatory (spectroscopic mode of ISOPHOT and ISOCAM). We compare them to the spectra of four Wolf-Rayet stars: WR78, WR134, WR136, and WR147 in the same wavelength range. The mid-infrared spectrum of SS 433 mainly shows HI and HeI emission lines and is very similar to the spectrum of WR147, a WN8(h)+B0.5V binary. The 2-12 micron continuum emission of SS 433 corresponds to optically thin and partially optically thick free-free emission, from which we calculate a mass loss rate of 2-3 x 10^{-4} Msun/yr if the wind is homogeneous and a third of these values if it is clumped. This is consistent with a strong stellar wind from a WN star. However, following recent studies concluding that the mass donor star of SS 433 is not a Wolf-Rayet star, we propose that this strong wind out flows from a geometrically thick envelope of material that surrounds the compact object like a stellar atmosphere, imitating the Wolf-Rayet phenomenon. This wind could also wrap the mass donor star, and at larger distances (~ 40 AU), it might form a dust envelope from which the thermal emission, detected with ISOPHOT at 25 micron and 60 micron, would originate. This wind also probably feeds the material that is ejected in the orbital plane of the binary system and that forms the equatorial outflow detected in radio at distances > 100 AU.
Ábrahám Peter
Fuchs Ya"el
Koch Miramond L.
No associations
LandOfFree
SS 433 : a phenomenon imitating a Wolf-Rayet star does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with SS 433 : a phenomenon imitating a Wolf-Rayet star, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and SS 433 : a phenomenon imitating a Wolf-Rayet star will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-428145