The ALPINE-CRISTAL-JWST Survey: The Tully-Fisher Relation at $z = 4-6$

Abstract

The Tully-Fisher relation provides a fundamental link between galaxy mass and their kinematics. Although its evolution is relatively well constrained up to cosmic noon, observational probes at higher redshifts remain scarce. In this work, we investigate the stellar and baryonic Tully-Fisher relations (TFRs) at $z=4-6$ by analyzing JWST/NIRSpec IFU observations of 18 main-sequence star-forming galaxies belonging to the ALPINE-CRISTAL-JWST survey. We apply a morpho-kinematic disk classification scheme, finding five disk-like galaxies and a survey disk fraction of $0.28\pm0.11$. These disk galaxies span stellar masses of $10^{9.5-10.5}\,M_\odot$, intrinsic rotational velocities of $91-127\,{\rm km\,s^{-1}}$, and intrinsic velocity dispersions of $66-129\,{\rm km\,s^{-1}}$. For both versions of the TFR, we find that the ALPINE-CRISTAL-JWST disks lie below the local relations and are likely offset from those reported at cosmic noon ($z\approx2.3$). By fixing the TFR slope to the $z=0$ value, we measure zero-point offsets for the stellar-mass TFR of $-0.96\pm0.18$ dex and $-0.50\pm0.18$ dex relative to the local Universe and cosmic noon, respectively. For the baryonic TFR, we find zero-point offsets of $-0.57\pm0.20$ dex and $-0.30\pm0.20$ dex with respect to the local Universe and cosmic noon relations. Our measurements are consistent with the redshift evolution of the zero-points of both TFRs being driven by the evolution of dark matter halo properties with cosmic time, modulated by a reduced contribution of dark matter to the dynamical mass on the galaxy scale.