Novel method for constraining the influence of dark matter hierarchical assembly on satellite distributions and other observable population statistics
Lead Research Organisation:
University of Southampton
Department Name: Sch of Physics and Astronomy
Abstract
The influence of dark matter on galaxies is yet to be fully understood. Semi-Analytic, Semi-Empirical and hydrodynamical simulations use dark matter to inform the galaxy mergers, masses and positions. However, these simulations are limited in size and must therefore run a finite number of merger trees or a finite sized box. This limitation introduces inconsistencies or incompleteness in the total galaxy statistics particularly at high masses. We use a novel approach in empirical galaxy formation models forgoing the classical dark matter merger trees using instead a statistical outlook on the accretion history to be able to create less biased and more comprehensive statistics of the observables used to constrain galaxy populations. The model will be constrained using abundance matching, halo richness in Sloan digital sky survey and observed pair fraction/merger rates. We will then make predictions and test proposed models to create statistics on other observables such as galaxy morphologies, Sersic index, intra cluster light etc. This extensive project will be published in 3 papers: A methodology paper describing the constraints and the new approach. A second paper presenting predictions to be validated against a variety of data. A final paper where we use the new technique in tandem with other modelling methods.
Organisations
Publications
Grylls P
(2019)
A statistical semi-empirical model: satellite galaxies in groups and clusters
in Monthly Notices of the Royal Astronomical Society
Grylls P
(2019)
Predicting fully self-consistent satellite richness, galaxy growth and starformation rates from the STastical sEmi-Empirical modeL steel.
in Monthly Notices of the Royal Astronomical Society
Grylls Philip J.
(2020)
The significant effects of stellar mass estimation on galaxy pair fractions
in arXiv e-prints
Studentship Projects
Project Reference | Relationship | Related To | Start | End | Student Name |
---|---|---|---|---|---|
ST/N504300/1 | 01/10/2015 | 31/03/2021 | |||
1860169 | Studentship | ST/N504300/1 | 01/10/2016 | 30/06/2020 | Philip Grylls |
Description | I have developed a novel new code STEEL that is unique in design for exploring the distribution of satellite galaxies. We have identified that many previous stellar-mass halo mass relations are not consistent with LCDM cosmology. We have identified that the SMHM relation is a large source os systematic error in the observed galaxy pair fraction. |
Exploitation Route | My model will be used by future researchers and research students. |
Sectors | Other |
Title | STEEL: the STastical sEmi-Empirical modeL |
Description | STEEL is a novel semi-empirical model developed during the PhD. |
Type Of Material | Improvements to research infrastructure |
Year Produced | 2018 |
Provided To Others? | No |
Impact | Three direct papers contributions to others and a tool for masters/project students to use |
Description | Nottingham Talk |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | National |
Primary Audience | Postgraduate students |
Results and Impact | I gave an invited talk to the Nottingham astrophysics group including postgraduate students, postdocs and staff on my first paper 'A Satistical Semi-Empirical model:...'. |
Year(s) Of Engagement Activity | 2018 |