The role of wind driving in OB star bow nebulae
arXiv:2003.11585 · doi:10.1093/mnras/staa838
Abstract
Bow-shaped mid-infrared emission regions have been discovered in satellite observations of numerous late-type O and early-type B stars with moderate velocities relative to the ambient interstellar medium. Previously, hydrodynamical bow shock models have been used to study this emission. It appears that such models are incomplete in that they neglect kinetic effects associated with long mean free paths of stellar wind particles, and the complexity of Weibel instability fronts. Wind ions are scattered in the Weibel instability and mix with the interstellar gas. However, they do not lose their momentum and most ultimately diffuse further into the ambient gas like cosmic rays, and share their energy and momentum. Lacking other coolants, the heated gas transfers energy to interstellar dust grains, which radiate it. This process, in addition to grain photo-heating, provides the energy for the emission. A weak R-type ionization front, formed well outside the infrared emission region, generally moderates the interstellar gas flow into the emission region. The theory suggests that the infrared emission process is limited to cases of moderate stellar peculiar velocities, evidently in accord with the observations.
arXiv comment11 pages, 3 figures, accepted for MNRAS
References in corpus (23)
- Simulations of Ion Acceleration at Non-relativistic Shocks. I. Acceleration Efficiency
- The empirical metallicity dependence of the mass-loss rate of O- and early B-type stars
- Simulations of Ion Acceleration at Non-relativistic Shocks. II. Magnetic Field Amplification
- E-BOSS: an Extensive stellar BOw Shock Survey. I: Methods and First Catalogue
- A comprehensive search for stellar bowshock nebulae in the Milky Way: a catalog of 709 mid-infrared selected candidates
- Models of the circumstellar medium of evolving, massive runaway stars moving through the Galactic plane
- Wind bubbles within H II regions around slowly moving stars
- E-BOSS: An Extensive stellar BOw Shock Survey. II. Catalogue second release
- Infrared Emission and the Destruction of Dust in HII regions
- Blowing in the wind: The dust wave surrounding Ori AB
- Bow shock nebulae of hot massive stars in a magnetized medium
- Plasma Diagnostics of the Interstellar Medium with Radio Astronomy
- Kinetic simulations of nonrelativistic perpendicular shocks of young supernova remnants. III. Magnetic reconnection
- On the observability of bow shocks of Galactic runaway OB stars
- Thermal emission from bow shocks I: 2D Hydrodynamic Models of the Bubble Nebula
- MHD-shock structures of astrospheres: Cephei-like astrospheres
- Infrared Photometric Properties of 709 Candidate Stellar Bowshock Nebulae
- Dynamics of H II regions around exiled O stars
- Bow shocks, bow waves, and dust waves. I. Strong coupling limit
- Modelling multi-wavelength observational characteristics of bow shocks from runaway early type stars
- Demonstration of a novel method for measuring mass-loss rates for massive stars
- Bow shocks, bow waves, and dust waves. II. Beyond the rip point
- Bow shocks, bow waves, and dust waves. III. Diagnostics