Galaxy And Mass Assembly (GAMA): Estimating galaxy group masses via caustic analysis

Alpaslan, Mehmet; Robotham, Aaron S.G.; Driver, Simon; Norberg, Peder; Peacock, John A.; Baldry, Ivan; Bland-Hawthorn, Joss; Brough, Sarah; Hopkins, Andrew M.; Kelvin, Lee S.; Liske, Jochen; Loveday, Jon; Merson, Alexander; Nichol, Robert C.; Pimbblet, Kevin

Abstract

We have generated complementary halo mass estimates for all the groups in the Galaxy And Mass Assembly Galaxy Group Catalogue (GAMA G 3 Cv1) using a modified caustic mass estimation algorithm, originally developed by Diaferio & Geller. We calibrate the algorithm by applying it on a series of nine GAMA mock galaxy light cones and investigate the effects of using different definitions for group centre and size. We select the set of parameters that provide median-unbiased mass estimates when tested on mocks, and generate mass estimates for the real group catalogue. We find that on average, the caustic mass estimates agree with dynamical mass estimates within a factor of 2 in 90.8 ± 6.1 per cent groups and compare equally well to velocity dispersion based mass estimates for both high- and low-multiplicity groups over the full range of masses probed by the G 3 Cv1. © 2012 The Authors Monthly Notices of the Royal Astronomical Society © 2012 RAS.

Citation

Alpaslan, M., Robotham, A. S., Driver, S., Norberg, P., Peacock, J. A., Baldry, I., Bland-Hawthorn, J., Brough, S., Hopkins, A. M., Kelvin, L. S., Liske, J., Loveday, J., Merson, A., Nichol, R. C., & Pimbblet, K. (2012). Galaxy And Mass Assembly (GAMA): Estimating galaxy group masses via caustic analysis. Monthly notices of the Royal Astronomical Society, 426(4), 2832-2846. https://doi.org/10.1111/j.1365-2966.2012.21020.x

• Journal Article Type: Article
• Acceptance Date: Mar 29, 2012
• Online Publication Date: Nov 11, 2012
• Publication Date: Nov 11, 2012
• Deposit Date: Feb 5, 2019
• Publicly Available Date: Feb 7, 2019
• Journal: Monthly Notices of the Royal Astronomical Society
• Print ISSN: 0035-8711
• Electronic ISSN: 1365-2966
• Publisher: Oxford University Press
• Peer Reviewed: Peer Reviewed
• Volume: 426
• Issue: 4
• Pages: 2832-2846
• DOI: https://doi.org/10.1111/j.1365-2966.2012.21020.x
• Keywords: Galaxies: groups: general; Galaxies: haloes; Dark matter; Large-scale structure of Universe
• Public URL: https://hull-repository.worktribe.com/output/591333
• Publisher URL: https://academic.oup.com/mnras/article/426/4/2832/1013164