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arXiv · 1104.4221

A New Method of the Corotation Radius Evaluation in our Galaxy

I. A. Acharova·Yu. N. Mishurov·M. R. Rasulova
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Abstract

We propose a new method for determination of the rotation velocity of the galactic spiral density waves, correspondingly, the corotation radius, $r_C$, in our Galaxy by means of statistical analysis of radial oxygen distribution in the galactic disc derived over Cepheids. The corotation resonance happens to be located at $r_C \sim 7.0 - 7.6 $ kpc, depending on the rate of gas infall on to the galactic disc, the statistical error being $\sim 0.3 - 0.4$ kpc. Simultaneously, the constant for the rate of oxygen synthesis in the galactic disc was determined. We also argue in favour of a very short time-scale formation of the galactic disc, namely: $t_f \sim 2$ Gyr. This scenario enables to solve the problem of the lack of intergalactic gas infall.

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I. A. Acharova, Yu. N. Mishurov, M. R. Rasulova. 2011-04-21. A New Method of the Corotation Radius Evaluation in our Galaxy. https://doi.org/10.1111/j.1745-3933.2011.01068.x

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