Résumé / Abstract Journal-club_Univers

Séminaire Univers /
Seminar Universe

« Dynamical mass inference of galaxy clusters with machine learning »

Doogesh Kodi Ramanah
DARK Cosmology Centre, Univ. Copenhagen (Copenhague, Danemark)

The abundance of galaxy clusters, the most massive gravitationally bound systems in the Universe, as described by the cluster mass function, is a fundamental probe of our cosmological model. I will review our recent work where we explore novel ways of inferring the dynamical mass of galaxy clusters from their projected phase-space distributions, i.e. the galaxy positions in the sky and their line-of-sight velocities. We present two complementary approaches of using machine learning to quantify uncertainties via normalizing flows (arXiv:2003:05951) and simulation-based inference (arXiv:2009.03340). I will illustrate the primary challenges inherent to the cluster mass estimation problem, and show how machine learning algorithms can provide a promising alternative to classical methods. I will also present the applications of our dynamical mass estimators to some well-known galaxy clusters, including around 900 galaxy clusters found in the SDSS Legacy Survey, culminating in a preliminary reconstruction of the cluster mass function.
mardi 27 octobre 2020 - 11:15
Webinaire
Institut d'Astrophysique de Paris
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