Astronomy and Astrophysics – Astrophysics
Scientific paper
2008-03-05
AJ, 135, 1946-1957 (2008)
Astronomy and Astrophysics
Astrophysics
accepted by AJ; 15p, 15fig available in jpg
Scientific paper
10.1088/0004-6256/135/5/1946
Three Galactic O-type stars belong to the rare class of Of?p objects: HD108, HD191612, and HD148937. The first two stars show a wealth of phenomena, including magnetic fields and strong X-ray emission, light variability, and dramatic periodic spectral variability. We present here the first detailed optical and X-ray study of the third Galactic Of?p star, HD148937. Spectroscopic monitoring has revealed low-level variability in the Balmer and HeII4686 lines, but constancy at HeI and CIII4650. The Ha line exhibits profile variations at a possible periodicity of ~7d. Model atmosphere fits yield T_{eff}=41000+-2000K, log(g)=4.0+-0.1, Mdot_{sph}<~ 10^{-7}Msol/yr and a surabondance of nitrogen by a factor of four. At X-ray wavelengths, HD148937 resembles HD108 and HD191612 in having a thermal spectrum dominated by a relatively cool component (kT=0.2keV), broad lines (>1700km/s), and an order-of-magnitude overluminosity compared to normal O stars (log [L_X^unabs/L_BOL] ~ -6).
Bond Howard E.
Martins Fabrice
Naze Yael
Pollock A. M. T.
Rauw Gregor
No associations
LandOfFree
HD148937: a multiwavelength study of the third Galactic member of the Of?p class 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 HD148937: a multiwavelength study of the third Galactic member of the Of?p class, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and HD148937: a multiwavelength study of the third Galactic member of the Of?p class will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-160786