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arXiv · 2302.02366

Evolution of the spiral structure of galaxies from the HST COSMOS field

V. P. Reshetnikov·A. A. Marchuk·I. V. Chugunov·P. A. Usachev·A. V. Mosenkov
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Abstract

We have investigated the pitch angle ($ψ$) of the spiral arms of galaxies in the Hubble Space Telescope COSMOS field. The sample consists of 102 face-on galaxies with a two-armed pattern at a mean redshift $\langle z \rangle \approx 0.5$. The typical values of $ψ$ in the spiral arms of distant galaxies are shown to be close to those for nearby spiral galaxies. Within one galaxy the scatter of $ψ$ for different arms is, on average, half the mean pitch angle. In the $z$ range from 1 to 0 we have found a tendency for $ψ$ to decrease. Our analysis of the $ψ$ distributions in galaxies at different redshifts is consistent with the assumption that in most of the galaxies at $z \leq 0.5$ the spiral arms are tidal in origin or they arose from transient recurrent instabilities in their disks.

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V. P. Reshetnikov, A. A. Marchuk, I. V. Chugunov, P. A. Usachev, A. V. Mosenkov. 2023-02-05. Evolution of the spiral structure of galaxies from the HST COSMOS field. https://doi.org/10.1134/s1063773722110111

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