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Arxiv: Disc asymmetry characterisation in JWST-observed galaxies at 1 < z < 4 Published: 11/18/2024 9:01:01 PM Updated: 11/18/2024 9:01:01 PM

Paper abstract: We present a novel technique using Fourier series and Laguerre polynomials torepresent morphological features of disc galaxies. To demonstrate the utilityof this technique, we study the evolution of asymmetry in a sample of discgalaxies drawn from the Extended Groth Strip and imaged by the JWST CosmicEvolution Early Release Science Survey as well as archival HST observations. Wemeasure disc asymmetry as the amplitude of the of the m = 1 Fourier harmonicfor galaxies within redshift ranges of 1 < z < 4. We show that when viewed inshorter rest frame wavelengths, disc galaxies have a higher asymmetry as theflux is dominated by star forming regions. We find generally low asymmetry atrest frame infrared wavelengths, where our metric tracks asymmetry inmorphological features such as bars and spiral arms. We show that higher massgalaxies have lower asymmetry and vice versa. Higher asymmetry in lower massgalaxies comes from lower mass galaxies (typically) having higher starformation rates. We measure the relation between disc galaxy asymmetry andredshift and find no conclusive relationship between them. We demonstrate theutility of the Fourier-Laguerre technique for recovering physically informativeasymmetry measurements as compared to rotational asymmetry measurements. Wealso release the software pipeline and quantitative analysis for each galaxy.