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arXiv · 1307.1824

Estimation of mass and cosmological constant of nearby spiral galaxies using galaxy rotation curve

B. Aryal·R. Pandey·N. Baral·U. Khanal·W. Saurer
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Abstract

An expression for rotational velocity of a test particle around the central mass in the invariant plane is derived. For this, a line element of Schwarzschild de-Sitter space-time is used to study the effect of cosmological constant ($Λ$) on the motion of both massive and massless particles. Using rotation curve data of 15 nearby spiral and barred spiral galaxies, we estimated the mass and $Λ$ of the galaxy. The mass of the galaxies are found to lie in the range 0.13-7.60 $\times$ 10$^{40}$ kg. The cosmological constant ($Λ$) is found to be negative ($-$0.03 to $-$0.10 $\times$ 10$^{-40}$ km$^{-2}$), suggesting the importance of anti-de Sitter space in the local bubble. Possible explanation of the results will be discussed.

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B. Aryal, R. Pandey, N. Baral, U. Khanal, W. Saurer. 2013-07-07. Estimation of mass and cosmological constant of nearby spiral galaxies using galaxy rotation curve. https://arxiv.org/abs/1307.1824

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