Dwarf Carbon Star Model Atmospheres And Synthetic Spectra

Rare White dwarf stars with carbon atmospheres

White dwarfs represent the endpoint of stellar evolution for stars with initial masses between approximately 0.07 M⊙ and 8-10 M⊙, where M⊙ is the mass of the Sun (more massive stars end their life as either black holes or neutron stars). The theory of stellar evolution predicts that the majority of white dwarfs have a core made of carbon and oxygen, which itself is surrounded by a helium layer ...

Hydrogen model atmospheres for white dwarf stars

We present a detailed calculation of model atmospheres for DA white dwarfs. Our atmosphere code solves the atmosphere structure in local thermodynamic equilibrium with a standard partial linearization technique, which takes into account the energy transfer by radiation and convection. This code incorporates recent improved and extended data base of collision induced absorption by molecular hydr...

ISO-SWS spectra of the C-rich AGB star R Scl and dynamical model atmospheres

We have monitored the spectral variations of the carbon rich AGB star R Scl in the 2−45 μm range using the ISO-SWS instrument. We have also computed hydrostatic and hydrodynamic model atmospheres and corresponding synthetic spectra representative for two phases of R Scl. There is good qualitative agreement between observations and models in the near IR. This demonstrates the theoretical progres...

Synthetic spectra of simulated terrestrial atmospheres containing possible biomarker gases.

NASA's proposed Terrestrial Planet Finder, a space-based interferometer, will eventually allow spectroscopic analyses of the atmospheres of extrasolar planets. Such analyses would provide information about the existence of life on these planets. One strategy in the search for life is to look for evidence of O3 (and hence O2) in a planet's atmosphere; another is to look for gases that might be p...

Synthetic Spectra and Mass Determination of the Brown Dwarf Gl229B