A New Method of the Corotation Radius Evaluation in our Galaxy

TL;DR

This paper introduces a novel statistical method to determine the corotation radius in our Galaxy using oxygen distribution data from Cepheids, providing insights into galactic dynamics and formation timescales.

Contribution

A new statistical approach for estimating the galactic corotation radius and oxygen synthesis rate, supporting a rapid formation scenario of the galactic disc.

Findings

Corotation radius estimated at 7.0 - 7.6 kpc

Oxygen synthesis rate constant determined

Galactic disc formation timescale around 2 Gyr

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.