Reliable mass calculation in spherical gravitating systems
journal contributionposted on 2019-06-21, 14:32 authored by FI Diakogiannis, GF Lewis, RA Ibata, M Guglielmo, MI Wilkinson, C Power
We present an innovative approach to the methodology of dynamical modelling, allowing practical reconstruction of the underlying dark matter mass without assuming both the density and anisotropy functions. With this, the mass–anisotropy degeneracy is reduced to simple model inference, incorporating the uncertainties inherent with observational data, statistically circumventing the mass–anisotropy degeneracy in spherical collisionless systems. We also tackle the inadequacy that the Jeans method of moments has on small data sets, with the aid of Generative Adversarial Networks: we leverage the power of artificial intelligence to reconstruct the projected line-of-sight velocity distribution non-parametrically. We show, with realistic numerical simulations of dwarf spheroidal galaxies, that we can distinguish between competing dark matter distributions and recover the anisotropy and mass profile of the system.
FID, GFL, and CP acknowledge support from Australian Research Council Discovery Project (DP140100198). FID also thanks the University of Western Australia for support through a Research Collaboration Awards (PG12105204). GFL thanks the European Southern Observatory (ESO) for support as a visiting astronomer and for hosting him in Garching where the final stages of the preparation of this publication were undertaken. RAI gratefully acknowledges support from a ‘Programme National Cosmologie et Galaxies’ grant.
CitationMonthly Notices of the Royal Astronomical Society, 2019, 482(3), pp. 3356–3372
Author affiliation/Organisation/COLLEGE OF SCIENCE AND ENGINEERING/Department of Physics and Astronomy
- VoR (Version of Record)