中文
相关论文

相关论文: Characterising dark matter haloes with computer vi…

200 篇论文

We study the density profile of a dwarf halo in the decaying dark matter (DDM) cosmology, using a new algorithm that resolves halo density profiles down to the innermost $700$ pc robustly with high efficiency. Following Schwarzschild's…

宇宙学与河外天体物理 · 物理学 2021-01-20 Jianxiong Chen , M. -C. Chu

We train graph neural networks on halo catalogues from Gadget N-body simulations to perform field-level likelihood-free inference of cosmological parameters. The catalogues contain $\lesssim$5,000 halos with masses $\gtrsim…

The structural and dynamic properties of the dark matter halos, though an important ingredient in understanding large-scale structure formation, require more conservative particle resolution than those required by halo mass alone in a…

宇宙学与河外天体物理 · 物理学 2022-11-23 Sujatha Ramakrishnan , Premvijay Velmani

The density profiles of dark matter halos are typically modeled using empirical formulae fitted to the density profiles of relaxed halo populations. We present a neural network model that is trained to learn the mapping from the raw density…

宇宙学与河外天体物理 · 物理学 2022-06-08 Luisa Lucie-Smith , Hiranya V. Peiris , Andrew Pontzen , Brian Nord , Jeyan Thiyagalingam , Davide Piras

We explore the impact of a LWDM cosmological scenario on the clustering properties of large-scale structure in the Universe. We do this by extending the halo model. The new development is that we consider two components to the mass density:…

宇宙学与河外天体物理 · 物理学 2013-05-29 Robert E. Smith , Katarina Markovic

We model the mass distributions of 40 high surface brightness spiral galaxies inside their optical radii, deriving parameters of mass models by matching the predicted velocities to observed velocity maps. We use constant mass-to-light disk…

天体物理学 · 物理学 2009-11-10 Eric I. Barnes , J. A. Sellwood , Arthur Kosowsky

Fuzzy dark matter (FDM) made of ultra-light bosonic particles is a viable alternative to cold dark matter (CDM) with clearly distinguishable small-scale features in collapsed structures. On large scales, it behaves gravitationally like CDM…

宇宙学与河外天体物理 · 物理学 2022-05-11 Bodo Schwabe , Jens C. Niemeyer

For many analyses in cosmology it is necessary to reconstruct the likely distribution of unobserved fields, such as dark matter or non-luminous baryons, from observed luminous tracers. The dominant approach in cosmology has been to use the…

宇宙学与河外天体物理 · 物理学 2025-12-16 Jordan Krywonos , Yurii Kvasiuk , Matthew C. Johnson , Moritz Münchmeyer

Using an analytic model calibrated against numerical simulations, we calculate the central densities of dark matter halos in a ``conventional'' cold dark matter model with a cosmological constant (LCDM) and in a ``tilted'' model (TLCDM)…

天体物理学 · 物理学 2007-05-23 S. M. Khairul Alam , James S. Bullock , David H. Weinberg

We present a proof-of-concept of a novel and fully Bayesian methodology designed to detect halos of different masses in cosmological observations subject to noise and systematic uncertainties. Our methodology combines the previously…

宇宙学与河外天体物理 · 物理学 2016-06-08 Alexander I. Merson , Jens Jasche , Filipe B. Abdalla , Ofer Lahav , Benjamin Wandelt , D. Heath Jones , Matthew Colless

We use numerical simulations in a Lambda CDM cosmology to model density profiles in a set of 16 dark matter haloes with resolutions of up to 7 million particles within the virial radius. These simulations allow us to follow robustly the…

We study the effects of mass and force resolution on the density profiles of galaxy-size Cold Dark Matter (CDM) halos in a flat, low-density cosmological model with vacuum energy. We show thatalthough increasing the mass and force…

天体物理学 · 物理学 2008-11-26 Anatoly Klypin , Andrey V. Kravtsov , James Bullock , Joel Primack

We use a set of N-body simulations employing a modified gravity (MG) model with Vainshtein screening to study matter and halo hierarchical clustering. As test-case scenarios we consider two normal branch Dvali-Gabadadze-Porrati (nDGP)…

宇宙学与河外天体物理 · 物理学 2017-07-19 Wojciech A. Hellwing , Kazuya Koyama , Benjamin Bose , Gong-Bo Zhao

In this proceeding, we briefly review three recent results. First, we show that halos formed in simulations with gas cooling are significantly rounder than halos formed in dissipationless $N$-body simulations. The increase in principle axis…

天体物理学 · 物理学 2016-11-03 Andrew R. Zentner , Savvas M. Koushiappas , Stelios Kazantzidis

We perform a series of simulations of a Galactic mass dark matter halo at different resolutions, our largest uses over three billion particles and has a mass resolution of 1000 M_sun. We quantify the structural properties of the inner dark…

If the concordance $\Lambda$CDM model is a true description of the universe, it should also properly predict the properties and structure of dark matter haloes, where galaxies are born. Using N-body simulations with a broad scale of mass…

天体物理学 · 物理学 2016-08-15 P. Nurmi , P. Heinämäki , E. Saar , M. Einasto , J. Holopainen , V. J. Martínez , J. Einasto

Conservative mass limits are often imposed on the dark matter halo catalogues extracted from N-body simulations. By comparing simulations with different mass resolutions, at $z=0$ we find that even for halos resolved by 100 particles, the…

宇宙学与河外天体物理 · 物理学 2021-12-08 Joaquin Armijo , Carlton M. Baugh , Nelson D. Padilla , Peder Norberg , Christian Arnold

The simplest scheme for predicting real galaxy properties after performing a dark matter simulation is to rank order the real systems by stellar mass and the simulated systems by halo mass and then simply assume monotonicity - that the more…

星系天体物理 · 物理学 2021-10-22 Stephanie Tonnesen , Jeremiah P. Ostriker

A fundamental prediction of the cold dark matter (CDM) model of structure formation is the existence of a vast population of dark matter haloes extending to subsolar masses. By contrast, other dark matter models, such as a warm thermal…

Guided image filter is a well-known local filter in image processing. However, the presence of halo artifacts is a common issue associated with this type of filter. This paper proposes an algorithm that utilizes gradient information to…

计算机视觉与模式识别 · 计算机科学 2023-07-11 Bo Wang , Yihong Wang , Xiubao Sui , Yuan Liu , Qian Chen