Dark Energy Survey Year 1 Results: Constraining Baryonic Physics in the Universe
Creators: name: Huang, Hung-Jin
name: Eifler, Tim
name: Mandelbaum, Rachel
name: Bernstein, Gary M.
name: Chen, Anqi
name: Choi, Ami
name: García-Bellido, Juan
name: Huterer, Dragan
name: Krause, Elisabeth
name: Rozo, Eduardo
name: Singh, Sukhdeep
name: Bridle, Sarah
name: DeRose, Joseph
name: Elvin-Pole, Jack
name: Fang, Xiao
name: Friedrich, Oliver
name: Gatti, Marco
name: Gaztanaga, Enrique
name: Gruen, Daniel
name: Hartley, Will
name: Hoyle, Ben
name: Jarvis, Mike
name: MacCrann, Niall
name: Rau, Markus
name: Miranda, Vivian
name: Prat, Judit
name: Sánchez, Carles
name: Samuroff, Simon
name: Troxel, Michael
name: Zuntz, Joe
name: Abbott, Tim
name: Aguena, Michel
name: Annis, James
name: Avila, Santiago
name: Becker, Matthew
name: Bertin, Emmanuel
name: Brooks, David
name: Burke, David
name: Rosell, Aurelio Carnero
name: Kind, Matias Carrasco
name: Carretero, Jorge
name: Castander, Francisco Javier
name: da Costa, Luiz
name: De Vicente, Juan
name: Dietrich, Jörg
name: Doel, Peter
name: Everett, Spencer
name: Flaugher, Brenna
name: Fosalba, Pablo
name: Frieman, Josh
name: Gruendl, Robert
name: Gutierrez, Gaston
name: Hinton, Samuel
name: Honscheid, Klaus
name: James, David
name: Kuehn, Kyler
name: Lahav, Ofer
name: Lima, Marcos
name: Maia, Marcio
name: Marshall, Jennifer
name: Menanteau, Felipe
name: Miquel, Ramon
name: Paz-Chinchón, Francisco
name: Malagón, Andrés Plazas
name: Romer, Kathy
name: Roodman, Aaron
name: Sanchez, Eusebio
name: Scarpine, Vic
name: Serrano, Santiago
name: Sevilla, Ignacio
name: Smith, Mathew
name: Soares-Santos, Marcelle
name: Suchyta, Eric
name: Swanson, Molly
name: Tarle, Gregory
name: Thomas, Diehl H.
name: Weller, Jochen
Publisher: name: arXiv
Year: 2020
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences
subject: FOS: Physical sciences

description: Measurements of large-scale structure are interpreted using theoretical predictions for the matter distribution, including potential impacts of baryonic physics. We constrain the feedback strength of baryons jointly with cosmology using weak lensing and galaxy clustering observables (3$\times$2pt) of Dark Energy Survey (DES) Year 1 data in combination with external information from baryon acoustic oscillations (BAO) and Planck cosmic microwave background polarization. Our baryon modeling is informed by a set of hydrodynamical simulations that span a variety of baryon scenarios; we span this space via a Principal Component (PC) analysis of the summary statistics extracted from these simulations. We show that at the level of DES Y1 constraining power, one PC is sufficient to describe the variation of baryonic effects in the observables, and the first PC amplitude ($Q_1$) generally reflects the strength of baryon feedback. With the upper limit of $Q_1$ prior being bound by the Illustris feedback scenarios, we reach $\sim 20\%$ improvement in the constraint of $S_8=σ_8(Ω_{\rm m}/0.3)^{0.5}=0.788^{+0.018}_{-0.021}$ compared to the original DES 3$\times$2pt analysis. This gain is driven by the inclusion of small-scale cosmic shear information down to 2.5 arcmin, which was excluded in previous DES analyses that did not model baryonic physics. We obtain $S_8=0.781^{+0.014}_{-0.015}$ for the combined DES Y1+Planck EE+BAO analysis with a non-informative $Q_1$ prior. In terms of the baryon constraints, we measure $Q_1=1.14^{+2.20}_{-2.80}$ for DES Y1 only and $Q_1=1.42^{+1.63}_{-1.48}$ for DESY1+Planck EE+BAO, allowing us to exclude one of the most extreme AGN feedback hydrodynamical scenario at more than $2 σ$.
description: 22 pages, 18 figures, 2 tables. accepted to MNRAS. A brief video summary of this paper is available at https://www.youtube.com/watch?v=QbeNwk5papU