On the possibility of determining the distance to the Galactic center from the geometry of spiral arm segments

I. I. Nikiforov; A. V. Veselova

doi:10.1515/astro-2017-0240

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arXiv · 1604.05233

On the possibility of determining the distance to the Galactic center from the geometry of spiral arm segments

I. I. Nikiforov·A. V. Veselova

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Abstract

A new approach to determining the solar galactocentric distance, $R_0$, from the geometry of spiral-arm segments is proposed. Geometric aspects of the problem are analyzed and a simplified three-point method for estimating $R_0$ from objects in a spiral segment is developed in order to test the proposed approach. An estimate of $R_0 = 8.44 \pm 0.45$ kpc is obtained by applying the method to masers with measured trigonometric parallaxes, and statistical properties of the $R_0$ estimation from spiral segments are analyzed.

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I. I. Nikiforov, A. V. Veselova. 2016-04-18. On the possibility of determining the distance to the Galactic center from the geometry of spiral arm segments. https://doi.org/10.1515/astro-2017-0240

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