DESI Peculiar Velocity Survey -- Fundamental Plane
Creators: name: Said, Khaled
name: Howlett, Cullan
name: Davis, Tamara
name: Lucey, John
name: Saulder, Christoph
name: Douglass, Kelly
name: Kim, Alex G.
name: Kremin, Anthony
name: Ross, Caitlin
name: Aldering, Greg
name: Aguilar, Jessica Nicole
name: Ahlen, Steven
name: BenZvi, Segev
name: Bianchi, Davide
name: Brooks, David
name: Claybaugh, Todd
name: Dawson, Kyle
name: de la Macorra, Axel
name: Dey, Biprateep
name: Doel, Peter
name: Fanning, Kevin
name: Ferraro, Simone
name: Font-Ribera, Andreu
name: Forero-Romero, Jaime E.
name: Gaztañaga, Enrique
name: Gontcho, Satya Gontcho A
name: Guy, Julien
name: Honscheid, Klaus
name: Kehoe, Robert
name: Kisner, Theodore
name: Lambert, Andrew
name: Landriau, Martin
name: Guillou, Laurent Le
name: Manera, Marc
name: Meisner, Aaron
name: Miquel, Ramon
name: Moustakas, John
name: Muñoz-Gutiérrez, Andrea
name: Myers, Adam
name: Nie, Jundan
name: Palanque-Delabrouille, Nathalie
name: Percival, Will
name: Prada, Francisco
name: Rossi, Graziano
name: Sanchez, Eusebio
name: Schlegel, David
name: Schubnell, Michael
name: Silber, Joseph Harry
name: Sprayberry, David
name: Tarlé, Gregory
name: Magana, Mariana Vargas
name: Weaver, Benjamin Alan
name: Wechsler, Risa
name: Zhou, Zhimin
name: Zou, Hu
Publisher: name: arXiv
Year: 2024
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences
subject: FOS: Physical sciences

description: The Dark Energy Spectroscopic Instrument (DESI) Peculiar Velocity Survey aims to measure the peculiar velocities of early and late type galaxies within the DESI footprint using both the Fundamental Plane and optical Tully-Fisher relations. Direct measurements of peculiar velocities can significantly improve constraints on the growth rate of structure, reducing uncertainty by a factor of approximately 2.5 at redshift 0.1 compared to the DESI Bright Galaxy Survey's redshift space distortion measurements alone. We assess the quality of stellar velocity dispersion measurements from DESI spectroscopic data. These measurements, along with photometric data from the Legacy Survey, establish the Fundamental Plane relation and determine distances and peculiar velocities of early-type galaxies. During Survey Validation, we obtain spectra for 6698 unique early-type galaxies, up to a photometric redshift of 0.15. 64\% of observed galaxies (4267) have relative velocity dispersion errors below 10\%. This percentage increases to 75\% if we restrict our sample to galaxies with spectroscopic redshifts below 0.1. We use the measured central velocity dispersion, along with photometry from the DESI Legacy Imaging Surveys, to fit the Fundamental Plane parameters using a 3D Gaussian maximum likelihood algorithm that accounts for measurement uncertainties and selection cuts. In addition, we conduct zero-point calibration using the absolute distance measurements to the Coma cluster, leading to a value of the Hubble constant, $H_0 = 76.05 \pm 0.35$(statistical) $\pm 0.49$(systematic FP) $\pm 4.86$(statistical due to calibration) $\mathrm{km \ s^{-1} Mpc^{-1}}$. This $H_0$ value is within $2σ$ of Planck Cosmic Microwave Background results and within $1σ$, of other low redshift distance indicator-based measurements.
description: 18 pages, 9 figures, 2 tables. Accepted for publication in MNRAS