Galaxy morphologies at cosmic noon with JWST: A foundation for exploring gas transport with bars and spiral arms

¹ Max-Planck-Institut für extraterrestische Physik (MPE), Giessenbachstraße 1., 85748 Garching, Germany
² Max-Planck-Institut für Astrophysik (MPA), Karl-Schwarzschild-Str. 1, 85748 Garching, Germany
³ Department of Physics, University of Oxford, Clarendon Laboratory, Parks Road, OX1 3PU Oxford, UK
⁴ Purple Mountain Observatory, Chinese Academy of Sciences, 10 Yuanhua Road, Nanjing 210023, China
⁵ Department of Physics, University of Bath, Claverton Down, Bath BA2 7AY, UK
⁶ Research School of Astronomy and Astrophysics, Australian National University, Weston Creek, ACT 2611, Australia
⁷ ARC Centre of Excellence for All-Sky Astrophysics in 3 Dimensions (ASTRO 3D), Canberra, ACT 2611, Australia
⁸ Kavli Institute for Astronomy and Astrophysics, Peking University, Beijing 100871, People’s Republic of China
⁹ Cosmic Dawn Center (DAWN), Copenhagen, Denmark
¹⁰ DTU-Space, Technical University of Denmark, Elektrovej 327, DK2800 Kgs. Lyngby, Denmark
¹¹ Department of Physics and Astronomy and PITT PACC, University of Pittsburgh, Pittsburgh, PA 15260, USA
¹² Osservatorio Astronomico di Padova, Vicolo dell’Osservatorio 5, Padova I-35122, Italy
¹³ School of Physics and Astronomy, Tel Aviv University, Tel Aviv 69978, Israel
¹⁴ Universidad de Concepción, Víctor Lamas 1290, Barrio Universitario, Concepción, Chile

^⋆ Corresponding author: jespejo@mpe.mpg.de

Received: 24 March 2025
Accepted: 11 June 2025

Abstract

The way in which radial flows shape galaxy structure and evolution remains an open question. Internal drivers of such flows, such as bars and spiral arms, known to mediate gas flows in the local Universe, are now observable at high redshift thanks to JWST’s unobscured view. We investigated the morphology of massive star-forming galaxies at 0.8 < z < 1.3 and 2.0 < z < 2.5, epochs marking the peak and decline of cosmic star formation, both well covered by kinematic surveys. Using JWST/NIRCam imaging, we visually classified 1451 galaxies, identified non-axisymmetric features, counted the number of spiral arms, analyzed nonparametric morphological indicators, and studied the dynamical support of the sample covered by kinematics (≈11% of the sample) as measured via v/σ. Disk galaxies dominate the sample (fraction 0.82 ± 0.03); among them, 0.48 ± 0.04 exhibit spiral structure and 0.11 ± 0.03 host bars. Both fractions decline with redshift, in agreement with previous studies. The proportion of two- and three-armed spirals remains largely unchanged across our redshift bins: approximately two-thirds show two arms and one-third show three arms in both bins. Notably, we find a higher incidence of three-armed spirals (≈0.30) than reported in the local Universe (≈0.20), suggesting a mild evolution in spiral arm multiplicity. Nonparametric morphological metrics strongly correlate with stellar mass but show no significant redshift evolution. Finally, kinematic analysis reveals a correlation between disk morphology and rotational support: most disks exhibit v/σ > 3 and median values of v/σ > 7 for spirals and v/σ > 5 for barred galaxies. This study establishes a population-wide framework for linking galaxy morphology and dynamics at cosmic noon, providing a key reference for future studies on the role of detailed structural features in galaxy evolution.