Astronomy and Astrophysics – Astrophysics
Scientific paper
2003-09-05
Astronomy and Astrophysics
Astrophysics
13 pages, 6 figures, To appear in the October issue of PASJ (vol.55, No. 5)
Scientific paper
This paper reports on an analysis of two Chandra X-ray observations of the young magnetic B star rho Ophiuchus S1. X-ray emission from the star was detected in both observations. The average flux was almost the same in both, but during each observation the flux showed significant time variations by a factor of two on timescales of 20-40 ks. Each spectrum could be fit by either an absorbed power-law model with a photon index of ~3 or a thin-thermal plasma model with a temperature of ~2 keV and an extremely low metal abundance (<~0.1 solar). The spectrum of the first observation has a weak-line feature at about 6.8 keV, which might correspond to highly ionized iron Kalpha. In contrast, the spectrum of the second observation apparently shows a weak edge absorption component at E~4 keV. The continuum emission and log LX/Lbol ~ -6 are similar to those of young intermediate-mass stars (Herbig Ae/Be stars), although the presence of a strong magnetic field (inferred from the detection of non-thermal radio emission) has drawn an analogy between rho Ophiuchus S1 and magnetic chemically peculiar (MCP) stars. If the X-ray emission is thermal, the small abundances that we derived might be related to the inverse first-ionization potential (FIP) effect, though there is no significant trend as a function of FIP from our model fits. If the emission is non-thermal, it might be produced by high-energy electrons in the magnetosphere.
Corcoran Michael F.
Hamaguchi Kenji
Imanishi Kensuke
No associations
LandOfFree
Chandra Observations of a Young Embedded Magnetic B Star in the rho Ophiuchus Cloud 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 Chandra Observations of a Young Embedded Magnetic B Star in the rho Ophiuchus Cloud, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Chandra Observations of a Young Embedded Magnetic B Star in the rho Ophiuchus Cloud will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-357483