中文
相关论文

相关论文: Systematically Asymmetric: A comparison of \hi\ pr…

200 篇论文

We have examined the morphological and dynamical HI symmetry properties of a sample of moderately inclined Sa galaxies which are classified as morphologically normal. The sample galaxies were known a prior to exhibit kinematic peculiarities…

天体物理学 · 物理学 2009-10-31 David A. Kornreich , Martha P. Haynes , Katherine P. Jore , R. V. E. Lovelace

Satellites are not randomly distributed around their central galaxies but show polar and planar structures. In this paper, we investigate the axis-asymmetry or lopsidedness of satellite galaxy distributions around isolated galaxies in a…

星系天体物理 · 物理学 2021-06-30 Peng Wang , Noam I. Libeskind , Marcel S. Pawlowski , Xi Kang , Wei Wang , Quan Guo , Elmo Tempel

Lopsidedness is common in disk galaxies, yet its origin and evolution remain unclear. Previous studies typically examined stellar and gas asymmetries separately, but a combined analysis offers a stronger probe of the mechanisms driving…

We present an analysis of the sky distribution of neutral hydrogen (HI) deficiency and spectral asymmetry for galaxies detected by the HI Parkes All-Sky Survey (HIPASS) as a function of projected environment density. Previous studies of…

星系天体物理 · 物理学 2020-10-21 T. N. Reynolds , T. Westmeier , L. Staveley-Smith

We give a summary of recent results on spatial and velocity biases in cosmological models. Progress in numerical techniques made it possible to simulate halos in large volumes with a such accuracy that halos survive in dense environments of…

天体物理学 · 物理学 2007-05-23 Anatoly Klypin

(Abridged). It has been recently shown that random motions of the neutral Hydrogen gas of the Triangulum galaxy (M33) exhibit a bisymmetric perturbation which is aligned with the minor axis of the galaxy, suggesting a projection effect. To…

星系天体物理 · 物理学 2023-09-27 P. Adamczyk , P. Amram , L. Chemin , B. Epinat , J. Braine , F. Combes , W. G. J. de Blok

We explore the potential of cross-correlating galaxies and peculiar velocities on non-linear scales to enhance cosmological constraints. Leveraging the \textsc{AbacusSummit} simulation suite and the halo occupation distribution (HOD)…

We examine the HI gas kinematics of galaxy pairs in two clusters and a group using Australian Square Kilometre Array Pathfinder (ASKAP) WALLABY pilot survey observations. We compare the HI properties of galaxy pair candidates in the Hydra I…

Line-of-sight velocities of gas and stars can constrain dark matter (DM) within rotationally supported galaxies if they trace circular orbits extensively. Photometric asymmetries may signify non-circular motions, requiring spectra with…

An asymmetry index is derived from ellipse-fitting to galaxy images, that gives weight to faint outer features and is not strongly redshift-dependent. These measures are made on a sample of 13 2MASS QSOs and their neighbour galaxies, and a…

天体物理学 · 物理学 2009-11-13 J. B. Hutchings , C. Proulx

Studying the atomic gas (HI) properties of the most isolated galaxies is essential to quantify the effect that the environment exerts on this sensitive component of the interstellar medium. We observed and compiled HI data for a well…

宇宙学与河外天体物理 · 物理学 2009-09-16 D. Espada , L. Verdes-Montenegro , E. Athanassoula , A. Bosma , W. K. Huchtmeier , S. Leon , U. Lisenfeld , J. Sabater , J. Sulentic , S. Verley , M. Yun

We present a study of kinematic asymmetries from the integral field spectroscopic surveys MAGPI and SAMI. By comparing the asymmetries in the ionsied gas and stars, we aim to disentangle the physical processes that contribute to kinematic…

Mass models of galactic disks traditionally rely on axisymmetric density and rotation curves, paradoxically acting as if their most remarkable asymmetric features, such as lopsidedness or spiral arms, were not important. In this article, we…

星系天体物理 · 物理学 2016-03-16 Laurent Chemin , Jean-Marc Hure , Caroline Soubiran , Stefano Zibetti , Stephane Charlot , Daisuke Kawata

We investigate the impact of nonaxisymmetric structure on estimates of galaxy inclinations and position angles. A new minimization technique is used to obtain estimates of inclination and position angle from a global fit to either…

天体物理学 · 物理学 2009-11-07 Eric I. Barnes , J. A. Sellwood

It is generally agreed that the rotational velocities of spiral galaxies indicate that a lot of matter is unseen. Hitherto, the majority of these mass models are all based on spherical symmetry, although this assumption is obviously not the…

天体物理学 · 物理学 2007-05-23 Pieter Buyle , Herwig Dejonghe , Gianfranco Gentile

Resolved rotation curves (RCs) are the gold-standard measurements for inferring dark matter distributions in $\Lambda$CDM and testing alternative theories of dynamics in galaxies. However they are expensive to obtain, making them…

星系天体物理 · 物理学 2025-09-23 Tariq Yasin , Harry Desmond

Large-scale asymmetries in the stellar mass distribution in galaxies are believed to trace non-equilibrium situations in the luminous and/or dark matter component. These may arise in the aftermath of events like mergers, accretion, and…

Observations of the neutral atomic hydrogen (HI) gas in galaxies are predominantly spatially unresolved, in the form of a global HI spectral line. There has been substantial work on quantifying asymmetry in global HI spectra (`global HI…

The morphology and kinematics of atomic Hydrogen (HI) gas in galaxies are influenced by both local and large scale cosmic environments. Differences in galaxy environment and interactions can leave distinct signatures in HI asymmetry,…

星系天体物理 · 物理学 2025-08-05 P. V. Bilimogga , E. Busekool , M. A. W. Verheijen , J. M. van der Hulst

Using the 2MASS Photometric Redshift catalogue we perform a number of statistical tests aimed at detecting possible departures from statistical homogeneity and isotropy in the large-scale structure of the Universe. Making use of the angular…

宇宙学与河外天体物理 · 物理学 2015-06-23 David Alonso , Ana Isabel Salvador , Francisco Javier Sánchez , Maciej Bilicki , Juan García-Bellido , Eusebio Sánchez