Constraints on dark matter to dark radiation conversion in the late universe with DES-Y1 and external data
Creators: name: Chen, Angela
name: Huterer, Dragan
name: Lee, Sujeong
name: Ferté, Agnès
name: Weaverdyck, Noah
name: Alves, Otavio Alonso
name: Leonard, C. Danielle
name: MacCrann, Niall
name: Raveri, Marco
name: Porredon, Anna
name: Di Valentino, Eleonora
name: Muir, Jessica
name: Lemos, Pablo
name: Liddle, Andrew
name: Blazek, Jonathan
name: Campos, Andresa
name: Cawthon, Ross
name: Choi, Ami
name: Dodelson, Scott
name: Elvin-Poole, Jack
name: Gruen, Daniel
name: Ross, Ashley
name: Secco, Lucas F.
name: Sevilla, Ignacio
name: Sheldon, Erin
name: Troxel, Michael A.
name: Zuntz, Joe
name: Abbott, Tim
name: Aguena, Michel
name: Allam, Sahar
name: Annis, James
name: Avila, Santiago
name: Bertin, Emmanuel
name: Bhargava, Sunayana
name: Bridle, Sarah
name: Brooks, David
name: Rosell, Aurelio Carnero
name: Kind, Matias Carrasco
name: Carretero, Jorge
name: Costanzi, Matteo
name: Crocce, Martin
name: da Costa, Luiz
name: Pereira, Maria Elidaiana da Silva
name: Davis, Tamara
name: Doel, Peter
name: Eifler, Tim
name: Ferrero, Ismael
name: Fosalba, Pablo
name: Frieman, Josh
name: Garcia-Bellido, Juan
name: Gaztanaga, Enrique
name: Gerdes, David
name: Gruendl, Robert
name: Gschwend, Julia
name: Gutierrez, Gaston
name: Hinton, Samuel
name: Hollowood, Devon L.
name: Honscheid, Klaus
name: Hoyle, Ben
name: James, David
name: Jarvis, Mike
name: Kuehn, Kyler
name: Lahav, Ofer
name: Maia, Marcio
name: Marshall, Jennifer
name: Menanteau, Felipe
name: Miquel, Ramon
name: Morgan, Robert
name: Palmese, Antonella
name: Paz-Chinchon, Francisco
name: Malagón, Andrés Plazas
name: Roodman, Aaron
name: Sanchez, Eusebio
name: Scarpine, Vic
name: Schubnell, Michael
name: Serrano, Santiago
name: Smith, Mathew
name: Suchyta, Eric
name: Tarle, Gregory
name: Thomas, Daniel
name: To, Chun-Hao
name: Varga, Tamas Norbert
name: Weller, Jochen
name: Wilkinson, Reese
Publisher: name: arXiv
Year: 2020
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences
subject: FOS: Physical sciences

description: We study a phenomenological class of models where dark matter converts to dark radiation in the low redshift epoch. This class of models, dubbed DMDR, characterizes the evolution of comoving dark matter density with two extra parameters, and may be able to help alleviate the observed discrepancies between early- and late-time probes of the universe. We investigate how the conversion affects key cosmological observables such as the CMB temperature and matter power spectra. Combining 3x2pt data from Year 1 of the Dark Energy Survey, {\it Planck}-2018 CMB temperature and polarization data, supernovae (SN) Type Ia data from Pantheon, and baryon acoustic oscillation (BAO) data from BOSS DR12, MGS and 6dFGS, we place new constraints on the amount of dark matter that has converted to dark radiation and the rate of this conversion. The fraction of the dark matter that has converted since the beginning of the universe in units of the current amount of dark matter, $ζ$, is constrained at 68\% confidence level to be $&lt;0.32$ for DES-Y1 3x2pt data, $&lt;0.030$ for CMB+SN+BAO data, and $&lt;0.037$ for the combined dataset. The probability that the DES and CMB+SN+BAO datasets are concordant increases from 4\% for the $Λ$CDM model to 8\% (less tension) for DMDR. The tension in $S_8 = σ_8 \sqrt{Ω_{\rm m}/0.3}$ between DES-Y1 3x2pt and CMB+SN+BAO is slightly reduced from $2.3σ$ to $1.9σ$. We find no reduction in the Hubble tension when the combined data is compared to distance-ladder measurements in the DMDR model. The maximum-posterior goodness-of-fit statistics of DMDR and $Λ$CDM model are comparable, indicating no preference for the DMDR cosmology over $Λ$CDM.
description: 23 pages, 11 figures. DES extensions group. Accepted by PRD