Astronomy and Astrophysics – Astrophysics
Scientific paper
2002-08-23
AJ, 124, 3325 (2002)
Astronomy and Astrophysics
Astrophysics
10 pages, 7 figures (jpg), to be published in AJ. The paper is also available at http://vela.astro.ulg.ac.be/Preprints/P75/ind
Scientific paper
10.1086/344481
Dynamical studies of superbubbles and Wolf-Rayet ring nebulae show discrepancies from the standard, adiabatic model for wind-blown bubbles. We therefore study the physical properties and kinematics of three candidate bubbles blown by single O stars, to evaluate whether these discrepancies are also found in these simpler objects. Our sample candidates are N44F, N44J, and N44M, in the outskirts of the HII complex N44 in the Large Magellanic Cloud. We have obtained ground-based and HST emission-line images and high dispersion echelle spectra for these objects. From the Halpha luminosities and the [OIII]/Halpha ratios of these nebulae, we estimate the spectral types of the ionizing stars to be O7V, O9.5V and O9.5V for N44F, N44J, and N44M, respectively. We find that the observed expansion velocity of 12 km/s for N44F is consistent with the stellar wind luminosity expected from the central ionizing star, as predicted by the standard bubble model. The observed upper limits for the expansion velocities of N44J and N44M are also compatible with the expected values, within the uncertainties. We also report the discovery in N44F of strongly-defined dust columns, similar to those seen in the Eagle Nebula. The photoevaporation of these dense dust features may be kinematically important and may actually govern the evolution of the shell. The inclusion of photoevaporation processes may thus undermine the apparent agreement between the observed bubble dynamics and the simple adiabatic models.
Chu Y.-H. Y.-H.
Gruendl Robert A.
Guerrero Martin A.
Naze Yael
Oey Sally M.
No associations
LandOfFree
Structure and Dynamics of Candidate O Star Bubbles in N44 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 Structure and Dynamics of Candidate O Star Bubbles in N44, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Structure and Dynamics of Candidate O Star Bubbles in N44 will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-94543