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

Andrej Dvornik*, Marcello Cacciato, Konrad Kuijken, Massimo Viola, Henk Hoekstra, Reiko Nakajima, Edo van Uitert, Margot Brouwer, Ami Choi, Thomas Erben, Ian Fenech Conti, Daniel J. Farrow, Ricardo Herbonnet, Catherine Heymans, Hendrik Hildebrand t, Andrew M. Hopkins, John McFarland, Peder Norberg, Peter Schneider, Cristóbal SifónEdwin Valentijn, Lingyu Wang

*Bijbehorende auteur voor dit werk

OnderzoeksoutputAcademicpeer review

26 Citaten (Scopus)
339 Downloads (Pure)


We investigate possible signatures of halo assembly bias for spectroscopically selected galaxy groups from the GAMA survey using weak lensing measurements from the spatially overlapping regions of the deeper, high-imaging-quality photometric KiDS 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 $0.85^{+0.37}_{-0.25}$, which is consistent with the $\Lambda$CDM prediction. Our galaxy groups have typical masses of $10^{13} M_{\odot}/h$, naturally complementing previous studies of halo assembly bias on galaxy cluster scales.
Originele taal-2English
Pagina's (van-tot)3251-3265
Aantal pagina's15
TijdschriftMonthly Notices of the Royal Astronomical Society
Nummer van het tijdschrift3
StatusPublished - 1-jul-2017

Citeer dit