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

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 $h\mathrm{/}{h}_z\ge 10$ 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.