相关论文: Constraining the mass of the Local Group

The Local Group (LG) is an environment accessible to detailed studies of galaxy formation, providing a complement to the early universe. In particular, spectroscopy of resolved stellar populations in the LG provides kinematical and chemical…

Our Galaxy, Andromeda and their companion dwarf galaxies form the Local Group. Most of the mass in and around it is believed to be dark matter rather than gas or stars, so its distribution must be inferred from the effect of gravity on the…

We review how dark matter is distributed in our local neighbourhood from an observational and theoretical perspective. We will start by describing first the dark matter halo of our own galaxy and in the Local Group. Then we proceed to…

The timing argument (TA) aims to find the total mass of the Local Group (LG) from the relative motions of the Milky Way (MW) and Andromeda Galaxy (M31). However, the classical TA always overestimates the LG mass, presumably because it does…

The spherical infall model first developed by Lema\^{i}tre and Tolman was modified in order to include the effects of a dark energy term. The resulting velocity-distance relation was evaluated numerically. This equation, when fitted to…

To study the local Hubble flow, we have run constrained dark matter (DM) simulations of the Local Group (LG) in the concordance LCDM and OCDM cosmologies, with identical cosmological parameters apart from the Lambda term. The simulations…

Using N-body simulations of flat, dark energy dominated cosmologies, we show that galaxies around simulated binary systems resembling the Local Group (LG) have low peculiar velocities, in good agreement with observational data. We have…

We examine the influence of the morphology-density(MD) relation and a wide range of simple models for biased galaxy formation on statistical measures of large scale structure. We contrast the behavior of local biasing models, in which the…

We introduce "Simulations Beyond The Local Universe" (SIBELIUS) that connect the Local Group to its cosmic environment. We show that introducing hierarchical small-scale perturbations to a density field constrained on large scales by…

Galaxy groups and low-mass clusters provide important laboratories in which to study X-ray gas physics and the interplay between galaxy evolution and environmental effects. The X-ray Multi-Mirror (XMM) Large Scale Structure (LSS) survey has…

Dark energy must be taken into account to estimate more reliably the amount of dark matter and how it is distributed in the local universe. For systems several Mpc across like the Local Group, we introduce three self-consistent independent…

The nature of the dark matter can affect the collapse time of dark matter haloes, and can therefore be imprinted in observables such as the stellar population ages and star formation histories of dwarf galaxies. In this paper we use high…

The measurement of the size of gravitationally bounded structures is an important test of gravity theories. For a given radius different theories can in fact predict a different gravitational stability mass (GSM) necessary to ensure the…

Local Group galaxies such as the Milky Way, the Magellanic Clouds, and M31 are being used by a number of international collaborations to search for microlensing events. Type and number of detections place constraints on dark matter and the…

We simulate the formation and evolution of the local galaxy population starting from initial conditions with a smoothed linear density field which matches that derived from the IRAS 1.2 Jy galaxy survey. Our simulations track the formation…

The Local Group (LG) consists of two giant spiral galaxies, the Milky Way (MW) and Andromeda (M31), and several smaller galaxies. The MW and M31 are approaching each other at a radial velocity of about $-109\,$km\,s$^{-1}$. Observational…

We attempt to fit the observed radial velocities (RVs) of ${\,{\sim}\,}30$ Local Group (LG) galaxies using a 3D dynamical model of it and its immediate environment within the context of the standard cosmological paradigm, $\Lambda$CDM. This…

Context: Several observations of the local Universe (LU) point towards the existence of very prominent structures. The presence of massive galaxy clusters and local super clusters on the one hand, but also large local voids and…

(abridged) Predictions of the Concordance Cosmological Model (CCM) of the structures in the environment of large spiral galaxies are compared with observed properties of Local Group galaxies. Five new most probably irreconcilable problems…

Key and still largely missing parameters for measuring the mass content and distribution of the Local Group are the proper motion vectors of its member galaxies. The problem when trying to derive the gravitational potential of the Local…