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Related papers: The splashback radius in symmetron gravity

200 papers

Motivated by the recent proposal of the splashback radius as a physical boundary of dark matter halos, we present a parallel computer code for Subhalo and PARticle Trajectory Analysis (SPARTA). The code analyzes the orbits of all simulation…

Cosmology and Nongalactic Astrophysics · Physics 2017-07-17 Benedikt Diemer

Recent work has shown that density profiles in the outskirts of dark matter halos can become extremely steep over a narrow range of radius. This behavior is produced by splashback material on its first apocentric passage after accretion. We…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-22 Susmita Adhikari , Neal Dalal , Robert T. Chamberlain

We use 1-dimensional numerical simulations to study spherical collapse in the f(R) gravity models. We include the nonlinear coupling of the gravitational potential to the scalar field in the theory and use a relaxation scheme to follow the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Alex Borisov , Bhuvnesh Jain , Pengjie Zhang

We study the gravitational collapse of an overdensity of nonrelativistic matter under the action of gravity and a chameleon scalar field. We show that the spherical collapse model is modified by the presence of a chameleon field. In…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 Ph. Brax , R. Rosenfeld , D. A. Steer

In this study, we define the novel splashback depth $\mathcal{D}$ and width $\mathcal{W}$ to examine how the splashback features of dark matter haloes are affected by the physical properties of haloes themselves. We use the largest…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-17 Qiaorong S. Yu , Stephanie O'Neil , Xuejian Shen , Mark Vogelsberger , Sownak Bose , Boryana Hadzhyska , Lars Hernquist , Rahul Kannan , Monica Wu , Ziang Wu

The splashback radius is one popular method of constraining the size of galaxy clusters, often measured through the logarithmic derivative of the galaxy number density profile. However, measuring the splashback radius through the galaxy…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-12 Talia M. O'Shea , Josh Borrow , Stephanie O'Neil , Mark Vogelsberger

The classification of dark matter halos as isolated hosts or subhalos is critical for our understanding of structure formation and the galaxy-halo connection. Most commonly, subhalos are defined to reside inside a spherical overdensity…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-11 Benedikt Diemer

Virtually any investigation involving dark matter halos relies on a definition of their radius, mass, and of whether they are a subhalo. The halo boundary is most commonly defined to include a spherical overdensity contrast (such as R200c,…

Cosmology and Nongalactic Astrophysics · Physics 2020-11-25 Benedikt Diemer

Cosmological parameters such as $\Omega_{\rm{M}}$ and $\sigma_{8}$ can be measured indirectly using various methods, including galaxy cluster abundance and cosmic shear. These measurements constrain the composite parameter $S_{8}$, leading…

Cosmology and Nongalactic Astrophysics · Physics 2024-06-27 Roan Haggar , Yuba Amoura , Charlie T. Mpetha , James E. Taylor , Kris Walker , Chris Power

We show that the projected number density profiles of SDSS photometric galaxies around galaxy clusters displays strong evidence for the splashback radius, a sharp halo edge corresponding to the location of the first orbital apocenter of…

We study the effects of screened modified gravity of the $f(R)$, dilaton and symmetron types on structure formation, from the quasi-linear to the non-linear regime, using semi-analytical methods. For such models, where the range of the new…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Philippe Brax , Patrick Valageas

We offer predictions of symmetron modified gravity in the neighborhood of realistic dark matter halos. The predictions for the fifth force are obtained by solving the nonlinear symmetron equation of motion in the spherical NFW…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Joseph Clampitt , Bhuvnesh Jain , Justin Khoury

A self-similar spherical collapse model predicts a dark matter (DM) splashback and accretion shock in the outskirts of galaxy clusters while misses a key ingredient of structure formation - processes associated with mergers. To fill this…

Cosmology and Nongalactic Astrophysics · Physics 2021-07-14 Congyao Zhang , Irina Zhuravleva , Andrey Kravtsov , Eugene Churazov

Recent advances in simulations and observations of galaxy clusters suggest that there exists a physical outer boundary of massive cluster-size dark matter haloes. In this work, we investigate the locations of the outer boundaries of dark…

Cosmology and Nongalactic Astrophysics · Physics 2021-10-25 Han Aung , Daisuke Nagai , Erwin T. Lau

The mass function of dark matter halos is one of the most fundamental statistics in structure formation. Many theoretical models (such as Press-Schechter theory) are based on the notion that it could be universal, meaning independent of…

Cosmology and Nongalactic Astrophysics · Physics 2020-11-25 Benedikt Diemer

The symmetron is a scalar field associated with the dark sector whose coupling to matter depends on the ambient matter density. The symmetron is decoupled and screened in regions of high density, thereby satisfying local constraints from…

Cosmology and Nongalactic Astrophysics · Physics 2011-11-23 Kurt Hinterbichler , Justin Khoury , Aaron Levy , Andrew Matas

We investigate the turnaround radius in the spherical collapse model, both in General Relativity and in modified gravity, in particular $f(R)$ scenarios. The phases of spherical collapse are marked by the density contrast in the instant of…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-19 Rafael C. C. Lopes , Rodrigo Voivodic , Luis Raul Abramo , Laerte Sodré

We examine the splashback structure of galaxy clusters using hydrodynamical simulations from the GIZMO run of The Three Hundred Project, focusing on the relationship between the stellar and dark matter components. We dynamically decompose…

Astrophysics of Galaxies · Physics 2026-03-18 Kris Walker , Aaron Ludlow , Chris Power , Alexander Knebe , Weiguang Cui

Context. Weak gravitational lensing offers a powerful method to investigate the projected matter density distribution within galaxy clusters, granting crucial insights into the broader landscape of dark matter on cluster scales. Aims. In…

In this work, we consider a semiclassical description of the spherically symmetric gravitational collapse with a massless scalar field. In particular, we employ an effective scenario provided by holonomy corrections from loop quantum…

General Relativity and Quantum Cosmology · Physics 2014-05-21 Yaser Tavakoli , Joao Marto , Andrea Dapor