A KiDS weak lensing analysis of assembly bias in GAMA galaxy groups

作者：Dvornik Andrej; Cacciato Marcello; Kuijken Konrad; Viola Massimo; Hoekstra Henk; Nakajima Reiko; van Uitert Edo; Brouwer Margot; Choi Ami; Erben Thomas; Conti Ian Fenech; Farrow Daniel J; Herbonnet Ricardo; Heymans Catherine; Hildebrandt Hendrik; Hopkins Andrew M; McFarland John; Norberg Peder; Schneider Peter; Sifon Cristobal; Valentijn Edwin; Wang Lingyu

来源：Monthly Notices of the Royal Astronomical Society, 2017, 468(3): 3251-3265.

DOI：10.1093/mnras/stx705

• gravitational lensing: weak
• methods: statistical
• surveys
• galaxies: haloes
• large-scale structure of Universe

We investigate possible signatures of halo assembly bias for spectroscopically selected galaxy groups from the Galaxy And Mass Assembly (GAMA) survey using weak lensing measurements from the spatially overlapping regions of the deeper, high-imaging-quality photometric Kilo-Degree Survey. We use GAMA groups with an apparent richness larger than 4 to identify samples with comparable mean host halo masses but with a different radial distribution of satellite galaxies, which is a proxy for the formation time of the haloes. We measure the weak lensing signal for groups with a steeper than average and with a shallower than average satellite distribution and find no sign of halo assembly bias, with the bias ratio of 0.85(-0.25)(+0.37), which is consistent with the Lambda cold dark matter prediction. Our galaxy groups have typical masses of 10(13) M-circle dot h(-1), naturally complementing previous studies of halo assembly bias on galaxy cluster scales.

• 出版日期2017-7
• 单位中国地震局