研究成果藝廊 > 星際與拱星介質
研究成果藝廊
星際與拱星介質
| Spiral density patterns calculated for the interaction between a dense stellar wind and a planet or brown dwarf orbiting the mass-losing star |
|
圖片來源: Kim and Taam
The three panels show the results for three different wind speeds: 0, 5 and 10 Mach, with Mach the number of times the local sound speed is exceeded. The circle indicates the orbit of the planet or brown dwarf, with its current location at the intersection of the dotted lines. The dashed lines denotes the opening angle of the spiral in a static medium, from which the corresponding models with faster winds start their spiral pattern. The resulting density enhancement is indicated by the color scale.
|
| The mass-loss that a Sun-like star undergoes at the end of its life manifests itself as a very dense stellar wind, which will interact with any brown dwarfs or planets that are orbiting the star. The gravitational interaction of the substellar mass objects with the strong stellar wind can potentially create a spiral density wave in the gaseous stellar outflow, with the exact tightness and the shape of the spiral depending on the wind speed and orbital properties. The figure below shows a comparison of the shape of the spiral pattern between models with wind Mach numbers of 0, 5, and 10 respectively, where the Mach number represents the number of times the wind speed exceeds the local sound velocity (Kim and Taam, 2012, ApJ, 744, 136). |
asiaa.sinica.edu.tw