On optical mass estimation methods for galaxy groups
Pearson, R.J.; Ponman, T.J.; Norberg, P.; Robotham, A.S.G.; Farr, W.M.
Professor Peder Norberg email@example.com
We examine the performance of a variety of different estimators for the mass of galaxy groups, based on their galaxy distribution alone. We draw galaxies from the Sloan Digital Sky Survey for a set of groups and clusters for which hydrostatic mass estimates based on high-quality Chandra X-ray data are available. These are used to calibrate the galaxy-based mass proxies, and to test their performance. Richness, luminosity, galaxy overdensity, rms radius and dynamical mass proxies are all explored. These different mass indicators all have their merits, and we argue that using them in combination can provide protection against being misled by the effects of dynamical disturbance or variations in star formation efficiency. Using them in this way leads us to infer the presence of significant non-statistical scatter in the X-ray based mass estimates we employ. We apply a similar analysis to a set of mock groups derived from applying a semi-analytic galaxy formation code to the Millennium dark matter simulation. The relations between halo mass and the mass proxies differ significantly in some cases from those seen in the observational groups, and we discuss possible reasons for this.
Pearson, R., Ponman, T., Norberg, P., Robotham, A., & Farr, W. (2015). On optical mass estimation methods for galaxy groups. Monthly Notices of the Royal Astronomical Society, 449(3), 3082-3106. https://doi.org/10.1093/mnras/stv463
|Journal Article Type||Article|
|Acceptance Date||Mar 2, 2015|
|Publication Date||May 21, 2015|
|Deposit Date||Feb 3, 2016|
|Publicly Available Date||Feb 12, 2016|
|Journal||Monthly Notices of the Royal Astronomical Society|
|Publisher||Royal Astronomical Society|
|Peer Reviewed||Peer Reviewed|
|Keywords||Galaxies: groups: general.|
Published Journal Article
This article has been accepted for publication in Monthly Notices of the Royal Astronomical Society ©: 2015 The Author Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.
You might also like
A sparse regression approach for populating dark matter haloes and subhaloes with galaxies
Solving small-scale clustering problems in approximate light-cone mocks
Making use of sub-resolution haloes in N-body simulations