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Abstract The baryonic Tully–Fisher relation (BTFR) has applications in galaxy evolution as a test bed for the galaxy–halo connection and in observational cosmology as a redshift-independent secondary distance indicator. This analysis leverages the 31,000+ galaxy Arecibo Legacy Fast ALFA (AreciboL-band Feed Array) Survey (ALFALFA) sample—which provides redshifts, velocity widths, and Hicontent for a large number of gas-bearing galaxies in the local universe—to fit and test an extensive local universe BTFR. The fiducial relation is fit using a 3000-galaxy subsample of ALFALFA, and is shown to be consistent with the full sample. This BTFR is designed to be as inclusive of ALFALFA and comparable samples as possible. Velocity widths measured via an automated method andM_bproxies extracted from survey data can be uniformly and efficiently measured for other samples, giving this analysis broad applicability. We also investigate the role of sample demographics in determining the best-fit relation. We find that the best-fit relations are changed significantly by changes to the sample mass range and to second order by changes to mass sampling, gas fraction, different stellar mass and velocity width measurements. We use a subset of ALFALFA with demographics that reflect the full sample to measure a robust BTFR slope of 3.30 ± 0.06. We apply this relation and estimate source distances, finding general agreement with flow-model distances as well as average distance uncertainties of ∼0.17 dex for the full ALFALFA sample. We demonstrate the utility of these distance estimates by applying them to a sample of sources in the Virgo vicinity, recovering signatures of infall consistent with previous work. 

Abstract We report the discovery of two companion sources to a strongly lensed galaxy SPT0418-47 (“ring”) at redshift 4.225, targeted by the JWST Early Release Science program. We confirm that these sources are at a similar redshift to the ring based on Hαdetected in the NIRSpec spectrum and [Cii]λ158μm line from the Atacama Large Millimeter/submillimeter Array (ALMA). Using multiple spectral lines detected in JWST/NIRSpec, the rest-frame optical to infrared images from NIRCam and MIRI and far-infrared dust continuum detected by ALMA, we argue that the newly discovered sources are actually lensed images of the same companion galaxy SPT0418-SE, hereafter referred to “SE,” located within 5 kpc in the source plane of the ring. The star formation rate derived using [Cii] and the dust continuum puts a lower limit of 17M_☉yr⁻¹, while the SFR_Hαis estimated to be >2 times lower, thereby confirming that SE is a dust-obscured star-forming galaxy. Analysis using optical strong line diagnostics suggests that SE has near-solar elemental abundance, while the ring appears to have supersolar metallicity O/H and N/O. We attempt to reconcile the high metallicity in this system by invoking early onset of star formation with continuous high star-forming efficiency or by suggesting that optical strong line diagnostics need revision at high redshift. We suggest that SPT0418-47 resides in a massive dark-matter halo with yet-to-be-discovered neighbors. This work highlights the importance of joint analysis of JWST and ALMA data for a deep and complete picture of the early universe. 

We present recent developments on Cornell’s 2nd generation z (redshift) and Early Universe Spectrometer (ZEUS-2). ZEUS-2 is a long-slit echelle-grating spectrometer, originally implemented to deliver R∼1000 spectroscopy in the 350-, and 450-micron telluric windows using NIST Transition-Edge Sensed (TES) bolometer arrays. We have expanded its capabilities to also cover the 200-micron window, and present first-light data for the new array from our 2019 observing campaign on the Atacama Pathfinder EXperiment (APEX) telescope. We also discuss the various enhancements we have implemented to improve observing efficiency and noise performance, including identifying and mitigating vibrations in hardware and improving the stability and robustness of the control software for the detector temperature. Furthermore, we have implemented several software routines to interface with the telescope control systems. These improvements, demonstrated during our recent observing campaign in Nov-Dec 2021, resulted in enhanced reliability and ease of operation, as well as increased sensitivity. A data-driven software pipeline, leveraging data from all 300 detectors on the array to remove common-mode noise, was implemented, and noise performance was further improved by robustly detecting unstable detectors and disabling them during observations.