Stellar dynamics in the strong-lensing central galaxy of Abell 1201: a low stellar mass-to-light ratio, a large central compact mass and a standard dark matter halo

ABSTRACT We use the UniverseMachine to analyse the source of scatter between the central galaxy mass, the total stellar mass in the halo, and the dark matter halo mass, for massive (Mvir > 1013 M⊙) haloes. We also propose a new halo mass estimator, the cen+N mass: the sum of the stellar mass of the central and the N most massive satellites. We show that, when real space positions are perfectly known, the cen+N mass has scatter competitive with that of richness-based estimators. However, in redshift space, using a simple cluster finder, the cen+N mass suffers less from projection effects in the UniverseMachine model. The cen+N mass is therefore a potential candidate to constrain cosmology with upcoming spectroscopic data from DESI. We analyse the scatter in stellar mass at fixed halo mass and show that the total stellar mass in a halo is uncorrelated with secondary halo properties, but that the central stellar mass is a function of both halo mass and halo age. This is because central galaxies in older haloes have had more time to grow via accretion. If the UniverseMachine model is correct, this implies that haloes selected using the centrals stellar mass will be biased old and that accurate galaxy-halo modelling of mass selected samples therefore needs to consider halo age in addition to mass.

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Two-component galaxy models with a central BH – II. The ellipsoidal case

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa3338 ◽

2020 ◽

Vol 500 (1) ◽

pp. 1054-1070

Author(s):

Luca Ciotti ◽

Antonio Mancino ◽

Silvia Pellegrini ◽

Azadeh Ziaee Lorzad

Keyword(s):

Dark Matter ◽

Stellar Dynamics ◽

Azimuthal Velocity ◽

Dark Matter Halo ◽

Gas Flows ◽

Total Density ◽

Density Distributions ◽

Stellar Component ◽

Two Component ◽

Analytical Formulae

ABSTRACT Recently, two-component spherical galaxy models have been presented, where the stellar profile is described by a Jaffe law, and the total density by another Jaffe law, or by an r−3 law at large radii. We extend these two families to their ellipsoidal axisymmetric counterparts: the JJe and J3e models. The total and stellar density distributions can have different flattenings and scale lengths, and the dark matter halo is defined by difference. First, the analytical conditions required to have a nowhere negative dark matter halo density are derived. The Jeans equations for the stellar component are then solved analytically, in the limit of small flattenings, also in the presence of a central BH. The azimuthal velocity dispersion anisotropy is described by the Satoh k-decomposition. Finally, we present the analytical formulae for velocity fields near the centre and at large radii, together with the various terms entering the virial theorem. The JJe and J3e models can be useful in a number of theoretical applications, e.g. to explore the role of the various parameters (flattening, relative scale lengths, mass ratios, rotational support) in determining the behaviour of the stellar kinematical fields before performing more time-expensive integrations with specific galaxy models, to test codes of stellar dynamics and in numerical simulations of gas flows in galaxies.

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The Connection Between Galaxies and Their Dark Matter Halos

Annual Review of Astronomy and Astrophysics ◽

10.1146/annurev-astro-081817-051756 ◽

2018 ◽

Vol 56 (1) ◽

pp. 435-487 ◽

Cited By ~ 145

Author(s):

Risa H. Wechsler ◽

Jeremy L. Tinker

Keyword(s):

Dark Matter ◽

Galaxy Formation ◽

Cosmic Time ◽

Stellar Mass ◽

Dark Matter Halo ◽

Strong Function ◽

Galaxy Surveys ◽

Narrow Region ◽

Open Questions ◽

Galaxy Halo

In our modern understanding of galaxy formation, every galaxy forms within a dark matter halo. The formation and growth of galaxies over time is connected to the growth of the halos in which they form. The advent of large galaxy surveys as well as high-resolution cosmological simulations has provided a new window into the statistical relationship between galaxies and halos and its evolution. Here, we define this galaxy–halo connection as the multivariate distribution of galaxy and halo properties that can be derived from observations and simulations. This galaxy–halo connection provides a key test of physical galaxy-formation models; it also plays an essential role in constraints of cosmological models using galaxy surveys and in elucidating the properties of dark matter using galaxies. We review techniques for inferring the galaxy–halo connection and the insights that have arisen from these approaches. Some things we have learned are that galaxy-formation efficiency is a strong function of halo mass; at its peak in halos around a pivot halo mass of 1012M⊙, less than 20% of the available baryons have turned into stars by the present day; the intrinsic scatter in galaxy stellar mass is small, less than 0.2 dex at a given halo mass above this pivot mass; below this pivot mass galaxy stellar mass is a strong function of halo mass; the majority of stars over cosmic time were formed in a narrow region around this pivot mass. We also highlight key open questions about how galaxies and halos are connected, including understanding the correlations with secondary properties and the connection of these properties to galaxy clustering.

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Testing dark energy models with a new sample of strong-lensing systems

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa2760 ◽

2020 ◽

Vol 498 (4) ◽

pp. 6013-6033

Author(s):

Mario H Amante ◽

Juan Magaña ◽

V Motta ◽

Miguel A García-Aspeitia ◽

Tomás Verdugo

Keyword(s):

Dark Matter ◽

Cold Dark Matter ◽

Velocity Dispersion ◽

Cosmological Parameters ◽

Cosmic Acceleration ◽

Dark Matter Halo ◽

Measured Velocity ◽

Strong Lensing ◽

The Impact ◽

Einstein Radius

ABSTRACT Inspired by a new compilation of strong-lensing systems, which consist of 204 points in the redshift range 0.0625 < zl < 0.958 for the lens and 0.196 < zs < 3.595 for the source, we constrain three models that generate a late cosmic acceleration: the ω-cold dark matter model, the Chevallier–Polarski–Linder, and the Jassal–Bagla–Padmanabhan parametrizations. Our compilation contains only those systems with early-type galaxies acting as lenses, with spectroscopically measured stellar velocity dispersions, estimated Einstein radius, and both the lens and source redshifts. We assume an axially symmetric mass distribution in the lens equation, using a correction to alleviate differences between the measured velocity dispersion (σ) and the dark matter halo velocity dispersion (σDM) as well as other systematic errors that may affect the measurements. We have considered different subsamples to constrain the cosmological parameters of each model. Additionally, we generate a mock data of SLS to asses the impact of the chosen mass profile on the accuracy of Einstein radius estimation. Our results show that cosmological constraints are very sensitive to the selected data: Some cases show convergence problems in the estimation of cosmological parameters (e.g. systems with observed distance ratio Dobs < 0.5), others show high values for the χ2 function (e.g. systems with a lens equation Dobs > 1 or high velocity dispersion σ > 276 km s−1). However, we obtained a fiduciary sample with 143 systems, which improves the constraints on each tested cosmological model.

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CONSTRAINING DARK MATTER HALO PROFILES AND GALAXY FORMATION MODELS USING SPIRAL ARM MORPHOLOGY. II. DARK AND STELLAR MASS CONCENTRATIONS FOR 13 NEARBY FACE-ON GALAXIES

The Astrophysical Journal ◽

10.1088/0004-637x/795/1/90 ◽

2014 ◽

Vol 795 (1) ◽

pp. 90 ◽

Cited By ~ 11

Author(s):

Marc S. Seigar ◽

Benjamin L. Davis ◽

Joel Berrier ◽

Daniel Kennefick

Keyword(s):

Dark Matter ◽

Galaxy Formation ◽

Stellar Mass ◽

Dark Matter Halo ◽

Spiral Arm ◽

Mass Concentrations

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Weak lensing reveals a tight connection between dark matter halo mass and the distribution of stellar mass in massive galaxies

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stz3314 ◽

2019 ◽

Vol 492 (3) ◽

pp. 3685-3707 ◽

Cited By ~ 5

Author(s):

Song Huang ◽

Alexie Leauthaud ◽

Andrew Hearin ◽

Peter Behroozi ◽

Christopher Bradshaw ◽

...

Keyword(s):

Dark Matter ◽

Stellar Mass ◽

Ex Situ ◽

Dark Matter Halo ◽

High Mass ◽

Weak Lensing ◽

Mass Relation ◽

Massive Galaxies ◽

Mass Distributions ◽

Tight Connection

ABSTRACT Using deep images from the Hyper Suprime-Cam (HSC) survey and taking advantage of its unprecedented weak lensing capabilities, we reveal a remarkably tight connection between the stellar mass distribution of massive central galaxies and their host dark matter halo mass. Massive galaxies with more extended stellar mass distributions tend to live in more massive dark matter haloes. We explain this connection with a phenomenological model that assumes, (1) a tight relation between the halo mass and the total stellar content in the halo, (2) that the fraction of in situ and ex situ mass at r <10 kpc depends on halo mass. This model provides an excellent description of the stellar mass functions (SMFs) of total stellar mass ($M_{\star }^{\mathrm{max}}$) and stellar mass within inner 10 kpc ($M_{\star }^{10}$) and also reproduces the HSC weak lensing signals of massive galaxies with different stellar mass distributions. The best-fitting model shows that halo mass varies significantly at fixed total stellar mass (as much as 0.4 dex) with a clear dependence on $M_{\star }^{10}$. Our two-parameter $M_{\star }^{\mathrm{max}}$–$M_{\star }^{10}$ description provides a more accurate picture of the galaxy–halo connection at the high-mass end than the simple stellar–halo mass relation (SHMR) and opens a new window to connect the assembly history of haloes with those of central galaxies. The model also predicts that the ex situ component dominates the mass profiles of galaxies at r < 10 kpc for log M⋆ ≥ 11.7. The code used for this paper is available online https://github.com/dr-guangtou/asap

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Mild Velocity Dispersion Evolution of massive galaxies since z~2

Proceedings of the International Astronomical Union ◽

10.1017/s1743921310002759 ◽

2009 ◽

Vol 5 (S262) ◽

pp. 184-187

Author(s):

Ignacio Trujillo ◽

A. Javier Cenarro

Keyword(s):

Dark Matter ◽

Velocity Dispersion ◽

Cosmic Time ◽

Stellar Mass ◽

Dark Matter Halo ◽

Massive Galaxies ◽

Strong Change ◽

First Time ◽

Lower Redshift

AbstractMaking use of public spectra from Cimatti et al. (2008), we measure for the first time the velocity dispersion of spheroid-like massive (M* ~ 1011M⊙) galaxies at z ~ 1.6. By comparing with galaxies of similar stellar mass at lower redshifts, we find evidence for a mild evolution in velocity dispersion, decreasing from ~240 kms−1 at z ~ 1.6 down to ~180 km s−1 at z ~ 0. Such mild evolution contrasts with the strong change in size (a factor of ~4) found for these type of objects in the same cosmic time, and it is consistent with a progressive larger role, at lower redshift, of the dark matter halo in setting the velocity dispersion of these galaxies. We discuss the implications of our results within the context of different scenarios proposed for the evolution of these massive objects.

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The AGN–galaxy–halo connection: The distribution of AGN host halo masses to z = 2.5

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stab312 ◽

2021 ◽

Author(s):

James Aird ◽

Alison L Coil

Keyword(s):

Dark Matter ◽

Distribution Function ◽

Mass Distribution ◽

Accretion Rate ◽

Cosmic Time ◽

Stellar Mass ◽

Dark Matter Halo ◽

Galaxy Halo ◽

Halo Masses ◽

Mass Distribution Function

Abstract It is widely reported, based on clustering measurements of observed active galactic nuclei (AGN) samples, that AGN reside in similar mass host dark matter halos across the bulk of cosmic time, with log $\mathcal {M}/\mathcal {M}_{\odot }\sim 12.5-13.0$ to z ∼ 2.5. We show that this is due in part to the AGN fraction in galaxies rising with increasing stellar mass, combined with AGN observational selection effects that exacerbate this trend. Here, we use AGN specific accretion rate distribution functions determined as a function of stellar mass and redshift for star-forming and quiescent galaxies separately, combined with the latest galaxy-halo connection models, to determine the parent and sub-halo mass distribution function of AGN to various observational limits. We find that while the median (sub-)halo mass of AGN, $\approx 10^{12}\mathcal {M}_{\odot }$, is fairly constant with luminosity, specific accretion rate, and redshift, the full halo mass distribution function is broad, spanning several orders of magnitude. We show that widely used methods to infer a typical dark matter halo mass based on an observed AGN clustering amplitude can result in biased, systematically high host halo masses. While the AGN satellite fraction rises with increasing parent halo mass, we find that the central galaxy is often not an AGN. Our results elucidate the physical causes for the apparent uniformity of AGN host halos across cosmic time and underscore the importance of accounting for AGN selection biases when interpreting observational AGN clustering results. We further show that AGN clustering is most easily interpreted in terms of the relative bias to galaxy samples, not from absolute bias measurements alone.

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A systematic search for galaxy proto-cluster cores at z ∼ 2

Proceedings of the International Astronomical Union ◽

10.1017/s1743921320001933 ◽

2019 ◽

Vol 15 (S359) ◽

pp. 166-167

Author(s):

Makoto Ando ◽

Kazuhiro Shimasaku ◽

Rieko Momose

Keyword(s):

Dark Matter ◽

Galaxy Formation ◽

Clustering Analysis ◽

Mass Function ◽

Stellar Mass ◽

Dark Matter Halo ◽

Massive Galaxies ◽

The Galaxy ◽

Mass Assembly ◽

Cluster Cores

AbstractA proto-cluster core is the most massive dark matter halo (DMH) in a given proto-cluster. To reveal the galaxy formation in core regions, we search for proto-cluster cores at z ˜ 2 in ˜1.5deg2 of the COSMOS field. Using pairs of massive galaxies (log (M*/Mʘ) ≥ 11) as tracers of cores, we find 75 candidate cores. A clustering analysis and the extended Press-Schechter model show that their descendant mass at z = 0 is consistent with Fornax-like or Virgo-like clusters. Moreover, using the IllustrisTNG simulation, we confirm that pairs of massive galaxies are good tracers of DMHs massive enough to be regarded as proto-cluster cores. We then derive the stellar mass function and the quiescent fraction for member galaxies of the 75 candidate cores. We find that stellar mass assembly and quenching are accelerated as early as z ˜ 2 in proto-cluster cores.

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