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arXiv · astro-ph/9611156

Mass of the Galaxy Inferred from Outer Rotation Curve

Mareki Honma·Yoshiaki Sofue
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Abstract

Using an outer rotation curve of the Galaxy, we explore the galactic constants and the mass of the Galaxy. We show that Θ_0 of 200 km/s is more favorable than the IAU standard value of 220 km/s, and also show that if Θ_0 is smaller than 207 km/s the rotation curve beyond 2R_0 is declining in Keplerian fashion. In the case of Θ_0= 200 km/s and R_0= 7.6 kpc, the total mass and the extent of the Galaxy inferred from the rotation curve are 2.0+/-0.3x 10^{11} M_\odot and 15 kpc, respectively. These results may significantly change the previous view of the Galaxy, that its outer region is dominated by a massive dark halo extending out to several tens of kpc.

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Mareki Honma, Yoshiaki Sofue. 1996-11-20. Mass of the Galaxy Inferred from Outer Rotation Curve. https://doi.org/10.1093/pasj%2F48.6.l103

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