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# First cosmology results using Type Ia Supernovae from the Dark Energy Survey: Constraints on cosmological parameters

Abbott, T.M.C., Allam, S. and Andersen, P. , The DES Collaboration (2019) First cosmology results using Type Ia Supernovae from the Dark Energy Survey: Constraints on cosmological parameters. The Astrophysical Journal Letters, 872 (2), [L30].

Record type: Article

## Abstract

We present the first cosmological parameter constraints using measurements of type Ia supernovae (SNe Ia) from the Dark Energy Survey Supernova Program (DES-SN). The analysis uses a subsample of 207 spectroscopically confirmed SNe Ia from the first three years of DES-SN, combined with a low-redshift sample of 122 SNe from the literature. Our "DES-SN3YR" result from these 329 SNe Ia is based on a series of companion analyses and improvements covering SN Ia discovery, spectroscopic selection, photometry, calibration, distance bias corrections, and evaluation of systematic uncertainties. For a flat ΛCDM model we find a matter density ${{\rm{\Omega }}}_{{\rm{m}}}=0.331\pm 0.038$. For a flat wCDM model, and combining our SN Ia constraints with those from the cosmic microwave background (CMB), we find a dark energy equation of state $w=-0.978\pm 0.059$, and ${{\rm{\Omega }}}_{{\rm{m}}}=0.321\pm 0.018$. For a flat w 0 w a CDM model, and combining probes from SN Ia, CMB and baryon acoustic oscillations, we find ${w}_{0}=-0.885\pm 0.114$ and ${w}_{a}=-0.387\,\pm \,0.430$. These results are in agreement with a cosmological constant and with previous constraints using SNe Ia (Pantheon, JLA).

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1811.02374 - Accepted Manuscript

Accepted/In Press date: 6 February 2019
e-pub ahead of print date: 21 February 2019
Published date: February 2019

## Identifiers

Local EPrints ID: 429875
URI: http://eprints.soton.ac.uk/id/eprint/429875
ISSN: 2041-8205
PURE UUID: 90d2d96c-d111-4ef4-a7a7-c8b8e84324ff
ORCID for Mark Sullivan: orcid.org/0000-0001-9053-4820
ORCID for Mathew Smith: orcid.org/0000-0002-3321-1432

## Catalogue record

Date deposited: 08 Apr 2019 16:30

## Contributors

Author: T.M.C. Abbott
Author: S. Allam
Author: P. Andersen
Author: Mark Sullivan
Author: Michael Childress
Author: Mathew Smith
Author: Charlotte Angus
Author: Philip Wiseman
Corporate Author: The DES Collaboration