The Composition and Evolutionary Status of Proxima Centauri
American Journal of Astronomy and Astrophysics
Volume 5, Issue 1, January 2017, Pages: 1-5
Received: Jan. 7, 2017; Accepted: Jan. 21, 2017; Published: Feb. 22, 2017
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Martin Beech, Campion College, The University of Regina, SK, Canada; Department of Physics, The University of Regina, SK, Canada
Corey McCowan, Campion College, The University of Regina, SK, Canada
Lowell Peltier, Department of Physics, The University of Regina, SK, Canada
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A suite of stellar evolution models has been used to estimate the mass and metallicity of Proxima Centauri (GJ 551, HIP 70890, V645 Cen). It is found that the observations are best described by an M ≈ 0.12 M star with a heavy element mass fraction in the range 0.004 < Z < 0.01 (or equivalently, a metallicity of -0.5 < [Fe/H] < -0.3). The derived metallicity of Proxima is distinctly at odds with that established for α Cen A and αCen B. It is argued that both the observational data as well as the evolutionary models for Proxima Centauri are consistent with an age of some 7 to 8 Gyr and that its (presently derived) physical characteristics are inconsistent with an in situ or coevally origin with the α Cen AB binary.
Proxima Centauri, α Cen A, α Cen B, Stellar Evolution, Metallicity
To cite this article
Martin Beech, Corey McCowan, Lowell Peltier, The Composition and Evolutionary Status of Proxima Centauri, American Journal of Astronomy and Astrophysics. Vol. 5, No. 1, 2017, pp. 1-5. doi: 10.11648/j.ajaa.20170501.11
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