Measuring the Virial Temperature of Galactic Halos through Electron Scatteringof Quasar Emission Lines

  title={Measuring the Virial Temperature of Galactic Halos through Electron Scatteringof Quasar Emission Lines},
  author={Abraham Loeb},
  journal={The Astrophysical Journal},
  • A. Loeb
  • Published 9 September 1998
  • Physics
  • The Astrophysical Journal
Semianalytic models of galaxy formation postulate the existence of virialized gaseous halos around galaxies at high redshifts. A small fraction of the light emitted by any high-redshift quasar is therefore expected to scatter off the free electrons in the halo of its host galaxy. The broadening of the scattered emission lines of the quasar can be used to measure the temperature of these electrons. For gas in virial equilibrium, the velocity width of the scattered line profile is larger by a… 

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