Stellar Velocity Dispersion of the Leo a Dwarf Galaxy

نویسندگان

  • Warren R. Brown
  • Margaret J. Geller
  • Scott J. Kenyon
  • Michael J. Kurtz
چکیده

We measure the first stellar velocity dispersion of the Leo A dwarf galaxy, σ = 9.3 ± 1.3 km s. We derive the velocity dispersion from the radial velocities of ten young B supergiants and two Hii regions in the central region of Leo A. We estimate a projected mass of 8 ± 2.7 × 10 M⊙ within a radius of 2, and a mass to light ratio of at least 20± 6 M⊙/L⊙. These results imply Leo A is at least ∼80% dark matter by mass. Subject headings: galaxies: individual (Leo A)

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تاریخ انتشار 2008