UCL Discovery
UCL home » Library Services » Electronic resources » UCL Discovery

The Splashback Feature around DES Galaxy Clusters: Galaxy Density and Weak Lensing Profiles

Chang, C; Baxter, E; Jain, B; Sanchez, C; Adhikari, S; Varga, TN; Fang, Y; ... Weller, J; + view all (2018) The Splashback Feature around DES Galaxy Clusters: Galaxy Density and Weak Lensing Profiles. The Astrophysical Journal , 864 (1) , Article 83. 10.3847/1538-4357/aad5e7. Green open access

[thumbnail of Chang_pdf.pdf]
Preview
Text
Chang_pdf.pdf - Published Version

Download (1MB) | Preview

Abstract

Splashback refers to the process of matter that is accreting onto a dark matter halo reaching its first orbital apocenter and turning around in its orbit. The clustercentric radius at which this process occurs, r sp, defines a halo boundary that is connected to the dynamics of the cluster. A rapid decline in the halo profile is expected near r sp. We measure the galaxy number density and weak lensing mass profiles around redMaPPer galaxy clusters in the first-year Dark Energy Survey (DES) data. For a cluster sample with mean M 200m mass ≈2.5 × 1014 M ⊙, we find strong evidence of a splashback-like steepening of the galaxy density profile and measure r sp = 1.13 ± 0.07 h −1 Mpc, consistent with the earlier Sloan Digital Sky Survey measurements of More et al. and Baxter et al. Moreover, our weak lensing measurement demonstrates for the first time the existence of a splashback-like steepening of the matter profile of galaxy clusters. We measure r sp = 1.34 ± 0.21 h −1 Mpc from the weak lensing data, in good agreement with our galaxy density measurements. For different cluster and galaxy samples, we find that, consistent with ΛCDM simulations, r sp scales with R 200m and does not evolve with redshift over the redshift range of 0.3–0.6. We also find that potential systematic effects associated with the redMaPPer algorithm may impact the location of r sp. We discuss the progress needed to understand the systematic uncertainties and fully exploit forthcoming data from DES and future surveys, emphasizing the importance of more realistic mock catalogs and independent cluster samples.

Type: Article
Title: The Splashback Feature around DES Galaxy Clusters: Galaxy Density and Weak Lensing Profiles
Open access status: An open access version is available from UCL Discovery
DOI: 10.3847/1538-4357/aad5e7
Publisher version: https://doi.org/10.3847/1538-4357/aad5e7
Language: English
Additional information: This is the published version of record. For information on re-use, please refer to the publisher’s terms and conditions.
Keywords: cosmology: observations; galaxies: clusters: general; galaxies: halos; gravitational lensing: weak
UCL classification: UCL
UCL > Provost and Vice Provost Offices > UCL BEAMS
UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences
UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences > Dept of Physics and Astronomy
URI: https://discovery.ucl.ac.uk/id/eprint/10035279
Downloads since deposit
0Downloads
Download activity - last month
Download activity - last 12 months
Downloads by country - last 12 months

Archive Staff Only

View Item View Item