Width variation in the spiral arms of distant galaxies from HST COSMOS field

We measured the slope of width growth with radius for spiral arms in 184 galaxies from the HST COSMOS field. The galaxies are viewed in an orientation close to face-on, and observed out to redshift z ≈ 1. The spiral arms are measured using an approximation of slices perpendicular to the arm originally proposed in Savchenko et al. (2020). It is shown that the typical values of the a parameter, which defines the increase of the arm width with the galactocentric distance, are, on average, significantly smaller for distant galaxies from the COSMOS field than for local ones. The average value is ⟨a⟩ = 0.06. It is shown that for the most galaxies, the width still increases with distance, and the opposite trend is observed for 25% of the cases. In the range of redshifts from 1 to 0, we observe a slight tendency for the parameter a to decrease.