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arXiv · 2401.05852

Edge-on galaxies in the HST COSMOS field: the evolution of stellar discs up to z$\sim$0.5

P. A. Usachev·V. P. Reshetnikov·S. S. Savchenko
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Abstract

We present a sample of 950 edge-on spiral galaxies found with the use of an artificial neural network in the Hubble Space Telescope COSMOS field. This is currently the largest sample of distant edge-on galaxies. For all galaxies we analyzed the 2D brightness distributions in the F814W filter and measured the radial and vertical exponential scales ($h$ and $h_z$ correspondingly) of the brightness distribution. By comparing the characteristics of distant galaxies with those of nearby objects, we conclude that thin stellar discs with $h/h_z \geq 10$ at $z \approx 0.5$ should be rarer than today. Both exponential scales of the stellar disc show evidence of luminosity-dependent evolution: in faint galaxies the $h$ and $h_z$ values do not change with $z$, in bright (and massive) spiral galaxies both scales, on average, grow towards our epoch.

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P. A. Usachev, V. P. Reshetnikov, S. S. Savchenko. 2024-01-11. Edge-on galaxies in the HST COSMOS field: the evolution of stellar discs up to z$\sim$0.5. https://arxiv.org/abs/2401.05852

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