The effect of environment on Type Ia supernovae in the Dark Energy Survey three-year cosmological sample Kelsey, L. Galbany González, Lluis Surveys Supernovae: general Distance scale Cosmology: observations This work was supported by the Science and Technology Facilities Council (grant number ST/P006760/1) through the DISCnet Centre forDoctoral Training. M.Sullivan and M.Smith acknowledge support from EU/FP7-ERC grant 615929, and PW acknowledges support from STFC grant ST/R000506/1. LG was funded by the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No. 839090. This work has been partially supported by the Spanish grant PGC2018-095317-B-C21 within the European Funds for Regional Development (FEDER). Funding for the DES Projects has been provided by the U.S. Department of Energy, the U.S. National Science Foundation, the Ministry of Science and Education of Spain, the Science and Technology Facilities Council of the United Kingdom, the Higher Education Funding Council for England, the National Center for Supercomputing Applications at the University of Illinois at Urbana-Champaign, the Kavli Institute of Cosmological Physics at the University of Chicago, the Center for Cosmology and Astro-Particle Physics at the Ohio StateUniversity, the Mitchell Institute for Fundamental Physics and Astronomy at Texas A&M University, Financiadora de Estudos e Projetos, Fundacao Carlos Chagas Filho de Amparo a Pesquisa do Estado do Rio de Janeiro, Conselho Nacional de Desenvolvimento Cientifico e Tecnologico and the Ministerio da Ciencia, Tecnologia e Inovacao, the Deutsche Forschungsgemeinschaft and the Collaborating Institutions in the Dark Energy Survey. The Collaborating Institutions are Argonne National Laboratory, the University of California at Santa Cruz, the University of Cambridge, Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas-Madrid, the University of Chicago, University College London, the DES-Brazil Consortium, the University of Edinburgh, the Eidgen ossische Technische Hochschule (ETH) Z urich, Fermi National Accelerator Laboratory, theUniversity of Illinois at Urbana Champaign, the Institut de Ciencies de l'Espai (IEEC/CSIC), the Institut de Fisica d'Altes Energies, Lawrence Berkeley National Laboratory, the Ludwig-Maximilians Universit at M unchen and the associated Excellence Cluster Universe, the University of Michigan, the National Optical Astronomy Observatory, the University of Nottingham, The Ohio State University, the University of Pennsylvania, the University of Portsmouth, SLAC National Accelerator Laboratory, Stanford University, the University of Sussex, Texas A&M University, and the OzDES Membership Consortium. The DES data management system is supported by the National Science Foundation under grant numbers AST-1138766 and AST-1536171. The DES participants from Spanish institutions are partially supported by MINECO under grants AYA2015-71825, ESP2015-66861, FPA2015-68048, SEV-2016-0588, SEV-2016-0597, and MDM-2015-0509, some of which include ERDF funds from the European Union. IFAE is partially funded by the CERCA program of the Generalitat de Catalunya. Research leading to these results has received funding from the European Research Council under the European Union's Seventh Framework Program (FP7/2007-2013) including ERC grant agreements 240672, 291329, and 306478. We acknowledge support from the Brazilian Instituto Nacional de Ciencia e Tecnologia (INCT) e-Universe (CNPq grant 465376/2014-2). This manuscript has been authored by Fermi Research Alliance, LLC under Contract No. DE-AC02-07CH11359 with the US Department of Energy, Office of Science, Office of High Energy Physics. The data underlying this paper are available in the DES3YR data release, available at https://www.darkenergysurvey.org/des-year-3- supernova-cosmology-results/, and in the online supplementary material. Supplementary data are available at MNRAS online. Table 1. Seeing-optimized image stack parameters. Analyses of Type Ia supernovae (SNe Ia) have found puzzling correlations between their standardized luminosities and host galaxy properties: SNe Ia in high-mass, passive hosts appear brighter than those in lower mass, star-forming hosts. We examine the host galaxies of SNe Ia in the Dark Energy Survey 3-yr spectroscopically confirmed cosmological sample, obtaining photometry in a series of 'local' apertures centred on the SN, and for the global host galaxy. We study the differences in these host galaxy properties, such as stellar mass and rest-frame U - R colours, and their correlations with SN Ia parameters including Hubble residuals. We find all Hubble residual steps to be >3 sigma in significance, both for splitting at the traditional environmental property sample median and for the step of maximum significance. For stellar mass, we find a maximal local step of 0.098 +/- 0.018mag; similar to 0.03mag greater than the largest global stellar mass step in our sample (0.070 +/- 0.017mag). When splitting at the sample median, differences between local and global U - R steps are small, both similar to 0.08mag, but are more significant than the global stellar mass step (0.057 +/- 0.017mag). We split the data into sub-samples based on SN Ia light-curve parameters: stretch (x(1)) and colour (c), finding that redder objects (c > 0) have larger Hubble residual steps, for both stellar mass and U - R, for both local and global measurements, of similar to 0.14mag. Additionally, the bluer (star-forming) local environments host a more homogeneous SN Ia sample, with local U - R rms scatter as low as 0.084 +/- 0.017mag for blue (c < 0) SNe Ia in locally blue U - R environments. 2021-05-05T10:33:19Z 2021-05-05T10:33:19Z 2020-12-21 info:eu-repo/semantics/article Monthly Notices of the Royal Astronomical Society, Volume 501, Issue 4, March 2021, Pages 4861–4876, [https://doi.org/10.1093/mnras/staa3924] http://hdl.handle.net/10481/68334 10.1093/mnras/staa3924 eng info:eu-repo/grantAgreement/EC/FP7/615929 info:eu-repo/grantAgreement/EC/H2020/839090 info:eu-repo/grantAgreement/EC/FP7/240672 info:eu-repo/grantAgreement/EC/FP7/291329 info:eu-repo/grantAgreement/EC/FP7/306478 http://creativecommons.org/licenses/by-nc-nd/3.0/es/ info:eu-repo/semantics/openAccess Atribución-NoComercial-SinDerivadas 3.0 España Oxford University Press