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Related papers: Made-to-Measure Modelling of Globular Clusters

200 papers

As a result of the slow action of two-body encounters, globular clusters develop mass segregation and attain a condition of only partial energy equipartition even in their central, most relaxed regions. Realistic numerical simulations show…

Astrophysics of Galaxies · Physics 2020-03-18 Stefano Torniamenti , Giuseppe Bertin , Paolo Bianchini

We present a novel approach to reconstruct gas and dark matter projected density maps of galaxy clusters using score-based generative modeling. Our diffusion model takes in mock SZ and X-ray images as conditional inputs, and generates…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-16 Alan Hsu , Matthew Ho , Joyce Lin , Carleen Markey , Michelle Ntampaka , Hy Trac , Barnabás Póczos

A mixture of Gaussians fit to a single curved or heavy-tailed cluster will report that the data contains many clusters. To produce more appropriate clusterings, we introduce a model which warps a latent mixture of Gaussians to produce…

Machine Learning · Computer Science 2014-08-12 Tomoharu Iwata , David Duvenaud , Zoubin Ghahramani

A mixture of Gaussians fit to a single curved or heavy-tailed cluster will report that the data contains many clusters. To produce more appropriate clusterings, we introduce a model which warps a latent mixture of Gaussians to produce…

Machine Learning · Statistics 2013-03-25 Tomoharu Iwata , David Duvenaud , Zoubin Ghahramani

We use the Made-to-Measure method to construct N-body realizations of self-similar, triaxial ellipsoidal halos having cosmologically realistic density profiles. Our implementation parallels previous work with a few numerical refinements,…

Astrophysics of Galaxies · Physics 2015-06-23 J. C. Malvido , J. A. Sellwood

We investigate the properties of globular clusters in a galaxy cluster, using the particle tagging method with a semi-analytical approach in a cosmological context. We assume globular clusters form from dark matter halo mergers and their…

Astrophysics of Galaxies · Physics 2022-12-21 So-Myoung Park , Jihye Shin , Rory Smith , Kyungwon Chun

We propose a novel technique to refine the modelling of galaxy clusters mass distribution using gravitational lensing. The idea is to combine the strengths of both "parametric" and "non-parametric" methods to improve the quality of the fit.…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-13 Eric Jullo , Jean-Paul Kneib

This thesis introduces a set of methods for testing models of modified gravity using galaxy clusters. In particular, a technique for constraining models with a chameleon screening is introduced. In addition, the outlined technique is…

Cosmology and Nongalactic Astrophysics · Physics 2020-11-18 Andrius Tamosiunas

A companion paper presents a worked model for evolution through inflation to initial conditions for an isocurvature model for structure formation. It is shown here that the model is consistent with the available observational constraints…

Astrophysics · Physics 2009-10-30 P. J. E. Peebles

We study the possible rotation of cluster galaxies, developing, testing and applying a novel algorithm which identifies rotation, if such does exist, as well as its rotational centre, its axis orientation, rotational velocity amplitude and,…

Cosmology and Nongalactic Astrophysics · Physics 2016-12-16 M. Manolopoulou , M. Plionis

We study the evolution of globular clusters with mass spectra under the influence of the steady Galactic tidal field, including the effects of velocity anisotropy. Similar to single-mass models, velocity anisotropy develops as the cluster…

Astrophysics · Physics 2009-10-31 K. Takahashi , H. M. Lee

Context. Machine-Learning (ML) solves problems by learning patterns from data, with limited or no human guidance. In Astronomy, it is mainly applied to large observational datasets, e.g. for morphological galaxy classification. Aims. We…

Astrophysics of Galaxies · Physics 2016-04-27 Mario Pasquato , Chul Chung

We demonstrate how the Syer & Tremaine made-to-measure method of stellar dynamical modelling can be adapted to model a rotating galactic bar. We validate our made-to-measure changes using observations constructed from the existing Shen et…

Astrophysics of Galaxies · Physics 2015-06-11 R. J. Long , Shude Mao , Juntai Shen , Yougang Wang

We study dynamical mass measurements of galaxy clusters contaminated by interlopers and show that a modern machine learning (ML) algorithm can predict masses by better than a factor of two compared to a standard scaling relation approach.…

Cosmology and Nongalactic Astrophysics · Physics 2016-11-09 M. Ntampaka , H. Trac , D. J. Sutherland , S. Fromenteau , B. Poczos , J. Schneider

In a series of three papers, we introduced a novel cluster formation model that describes the formation, growth, and disruption of star clusters in high-resolution cosmological simulations. We tested this model on a Milky Way-sized galaxy…

Astrophysics of Galaxies · Physics 2020-03-18 Hui Li , Oleg Gnedin

The parallel code NMAGIC is an implementation of a particle-based method to create made-to-measure models in agreement with observations of galaxies. It works by slowly correcting the particle weights of an evolving N-body system, until a…

Cosmology and Nongalactic Astrophysics · Physics 2012-07-30 Lucia Morganti , Ortwin Gerhard

If properly calibrated, the shapes of galaxy clusters can be used to investigate many physical processes: from feedback and quenching of star formation, to the nature of dark matter. Theorists frequently measure shapes using moments of…

Cosmology and Nongalactic Astrophysics · Physics 2020-11-11 David Harvey , Andrew Robertson , Sut-Ieng Tam , Mathilde Jauzac , Richard Massey , Jason Rhodes , Ian G. McCarthy

We present a novel method to recontruct the mass distribution of galaxy clusters from their gravitational lens effect on background galaxies. The method is based on a least-chisquare fit of the two-dimensional gravitational cluster…

Astrophysics · Physics 2009-10-28 Matthias Bartelmann , Ramesh Narayan , Stella Seitz , Peter Schneider

The majority of observed mass-to-light ratios of globular clusters are too low to be explained by `canonical' cluster models, in which dynamical effects are not accounted for. Moreover, these models do not reproduce a recently reported…

Astrophysics · Physics 2009-11-13 J. M. Diederik Kruijssen

In the context of theories of gravity modified to account for the observed dynamics of galactic systems without the need to invoke the existence of dark matter, a prediction often appears regarding low acceleration systems: wherever $a$…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 X. Hernandez , M. A. Jimenez