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We present a new method for modelling the kinematics of galaxies from interferometric observations by performing the optimization of the kinematic model parameters directly in visibility-space instead of the conventional approach of fitting velocity fields produced with the CLEAN algorithm in real-space. We demonstrate our method on ALMA observations of $^{12}$CO (2$-$1), (3$-$2) or (4$-$3) emission lines from an initial sample of 30 massive 850$\mu$m-selected dusty star-forming galaxies with far-infrared luminosities $\gtrsim$$\,10^{12}\,$L$_{\odot}$ in the redshift range $z \sim\,$1.2$-$4.7. Using the results from our modelling analysis for the 12 sources with the highest signal-to-noise emission lines and disk-like kinematics, we conclude the following: (i) Our sample prefers a CO-to-$H_2$ conversion factor, of $\alpha_{\rm CO} = 0.92 \pm 0.36$; (ii) These far-infrared luminous galaxies follow a similar Tully$-$Fisher relation between the circularized velocity, $V_{\rm circ}$, and baryonic mass, $M_{\rm b}$, as more typical star-forming samples at high redshift, but extend this relation to much higher masses $-$ showing that these are some of the most massive disk-like galaxies in the Universe; (iii) Finally, we demonstrate support for an evolutionary link between massive high-redshift dusty star-forming galaxies and the formation of local early-type galaxies using the both the distributions of the baryonic and kinematic masses of these two populations on the $M_{\rm b}\,-\,\sigma$ plane and their relative space densities.

Massive galaxies are expected to grow through different transformative evolutionary phases where high-redshift starburst galaxies and quasars are examples of such phases. The physical mechanisms driving these phases include companion galaxy interactions, active galactic nuclei feedback, and magnetic fields. Our aim is to characterize the physical properties and the environment of the submillimeter galaxy AzTEC-3 at z = 5.3 and the lensed quasar BRI 0952-0115 at z = 4.4, to set a limit on the polarization properties, as well as placing both in the broader context of galaxy evolution. We used full polarization, sub-arcsecond-resolution, ALMA band-7 observations of both BRI 0952-0115 and AzTEC-3 and detect [CII] line emission towards both galaxies, along with companions in each field. We present an updated gravitational lensing model for BRI 0952-0115. We present infrared luminosities, star-formation rates, and [CII] line to infrared luminosity ratios for each source. The [CII] emission line profile for both BRI 0952-0115 and AzTEC-3 exhibit a broad, complex morphology, indicating the possible presence of outflows. We present evidence of a 'gas bridge' between AzTEC-3 and a companion source. Using a simple dynamical mass estimate for the sources, we suggest that both systems are undergoing minor or major mergers. No polarization is detected for the [CII], placing an upper limit below that of theoretical predictions. Our results show that high-velocity wings are detected, indicating possible signs of massive outflows; however, the presence of companion galaxies can affect the final interpretation. Furthermore, the results provide additional evidence in support of the hypothesis that massive galaxies form in overdense regions, growing through interactions. Finally, strong, ordered magnetic fields are unlikely to exist at the kiloparsec scale in the two studied sources.

We utilise the unprecedented depth and resolution of recent early-release science (ERS) JWST observations to define the near-infrared counterparts of sub-millimetre selected galaxies (SMGs). We identify 45 SCUBA-2 SMG positions within The Cosmic Evolution Early Release Science Survey (CEERS) JWST/NIRCam fields. Through an analysis of multi-wavelength $p$-values, NIRCam colours and predicted SCUBA-2 fluxes, we define 43 JWST/NIRCam counterparts to the SCUBA-2 SMGs, finding a 63 per cent agreement with those identified in prior $HST$ studies. Using EaZy-py we fit the available HST and JWST observations to quantify the photometric redshifts of the NIRCam-SMGs, establishing a broad range of redshift from $z$$\approx$0.2$-$5.4 with a median of $z$$\approx$2.29, in agreement with other studies of SMGs. We analyse their rest-frame optical and near-infrared morphological properties (e.g. effective radius (R$_{\rm e}$), S\'ersic index ($n$), CAS, Gini and M$_{20}$), finding, on average, late-type disc-like morphologies with large scatter into the intermediate and merger regions of the non-parametric parameter space. For the non-merging galaxies, we find a median rest-frame optical size and S\'ersic index (and $1\sigma$ scatter) of R$_{\rm e}$=3.10$\pm$1.67kpc and $n$=0.96$\pm$0.66. Whilst in the rest-frame near-infrared we establish more compact, higher S\'ersic index morphologies (R$_{\rm e}$=1.64$\pm$0.97, $n$=1.85$\pm$0.63). We further establish that both the rest-frame optical and near-infrared effective radii correlate negatively (at a 2$\sigma$ level) with redshift whilst the S\'ersic index remains constant with cosmic time. Our results are consistent with the picture of inside-out galaxy evolution, with more centrally concentrated older stellar populations, and more extended, younger star-forming regions whose stellar emission is heavily attenuated in the central regions., Comment: Submitted for publication in A&A. Comments welcome. 18 pages

We present spatially resolved kinematics of 27 ALMA-identified dust-obscured star-forming galaxies (DSFGs) at $z\sim$1.3-2.6, as traced by H$\alpha$ emission using VLT/KMOS near-infrared integral field spectroscopy from the "KMOS-ALMA Observations of Submillimetre Sources" (KAOSS) Large Programme. We derive H$\alpha$ rotation curves and velocity dispersion profiles for the DSFGs, and find that among the 27 sources with bright, spatially extended H$\alpha$ emission, 24 display evidence for disc-like kinematics. We measure a median inclination-corrected velocity at 2.2$R_{\rm d}$ of $v_{\rm rot}=$190$\pm$40kms$^{-1}$ and intrinsic velocity dispersion of $\sigma_0=$87$\pm$6kms$^{-1}$ for these disc-like sources. The kinematics yield median circular velocities of $v_{\rm circ}=$230$\pm$20kms$^{-1}$ and dynamical masses within 2$R_{\rm e}$ ($\sim$7kpc radius) of $M_{\rm dyn}=$(1.1$\pm$0.2)$\times$10$^{11}$M$_\odot$. Compared to less actively star-forming galaxies, KAOSS DSFGs are both faster rotating with higher intrinsic velocity dispersions, but have similar $v_{\rm rot}/\sigma_0$ ratios, median $v/\sigma_0=$2.5$\pm$0.5. We suggest that the kinematics of the DSFGs are primarily rotation supported but with a non-negligible contribution from pressure support, which may be driven by star formation or mergers/interactions. We estimate the normalisation of the stellar mass Tully-Fisher relation (sTFR) for the disc-like DSFGs and compare it with local studies, finding no evolution at fixed slope between $z\sim$2 and $z\sim$0. Finally, we show that the kinematic properties of the DSFG population are consistent with them evolving into massive early-type galaxies, the dominant $z\sim$0 population at these masses., Comment: 24 pages, 15 figures, accepted for publication in MNRAS, updated author list