Observed Mass Profiles in Massive ETGs and Clusters and Implications for ΛCDM

AbstractEach component of a galaxy plays its own unique role in regulating the galaxy's evolution. In order to understand how galaxies form and evolve, it is therefore crucial to study the distribution and properties of each of the various components, and the links between them, both radially and vertically. The latter is only possible in edge-on systems. We present the HEROES project, which aims to investigate the 3D structure of the interstellar gas, dust, stars and dark matter in a sample of 7 massive early-type spiral galaxies based on a multi-wavelength data set including optical, NIR, FIR and radio data.

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DARK MATTER DYNAMICS AND INDIRECT DETECTION

Modern Physics Letters A ◽

10.1142/s0217732305017391 ◽

2005 ◽

Vol 20 (14) ◽

pp. 1021-1036 ◽

Cited By ~ 82

Author(s):

GIANFRANCO BERTONE ◽

DAVID MERRITT

Keyword(s):

Dark Matter ◽

Total Mass ◽

Galactic Center ◽

Direct Detection ◽

Indirect Detection ◽

Matter Distribution ◽

Dark Matter Distribution ◽

Particle Dark Matter ◽

The Universe ◽

Rule Out

Non-baryonic, or "dark", matter is believed to be a major component of the total mass budget of the Universe. We review the candidates for particle dark matter and discuss the prospects for direct detection (via interaction of dark matter particles with laboratory detectors) and indirect detection (via observations of the products of dark matter self-annihilations), focusing in particular on the Galactic center, which is among the most promising targets for indirect detection studies. The gravitational potential at the Galactic center is dominated by stars and by the supermassive black hole, and the dark matter distribution is expected to evolve on sub-parsec scales due to interaction with these components. We discuss the dominant interaction mechanisms and show how they can be used to rule out certain extreme models for the dark matter distribution, thus increasing the information that can be gleaned from indirect detection searches.

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2dF Spectroscopy of Globular Clusters in M104

Highlights of Astronomy ◽

10.1017/s1539299600015653 ◽

2005 ◽

Vol 13 ◽

pp. 199-199

Author(s):

Terry Bridges ◽

Steve Zepf ◽

Katherine Rhode ◽

Ken Freeman

Keyword(s):

Dark Matter ◽

Strong Evidence ◽

Total Mass ◽

Globular Clusters ◽

Total Sample ◽

Dark Matter Halo ◽

Large Radius ◽

Counter Rotation ◽

Spatial Coverage

AbstractWe have found 56 new globular clusters in M104 from 2dF multi-fiber spectroscopy, doubling the number of confirmed clusters, and extending the spatial coverage to 50 kpc radius. We find no significant rotation in the total sample, or for subsets split by color or radius. However, there are hints that the blue clusters have a higher rotation than the red clusters, and for counter-rotation of clusters at large radius. We find a total mass of M ~ 1 × 1012M⊙ and a (M/L)B =30 out to 50 kpc radius, which is strong evidence for a dark matter halo in M104.

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Black hole in balance with dark matter

International Journal of Modern Physics A ◽

10.1142/s0217751x20400503 ◽

2020 ◽

Vol 35 (02n03) ◽

pp. 2040050

Author(s):

Boris E. Meierovich

Keyword(s):

Black Hole ◽

Dark Matter ◽

Phase Equilibrium ◽

Vector Field ◽

Scalar Field ◽

Total Mass ◽

Metric Tensor ◽

Static Solutions ◽

Tensor Formula ◽

Galaxy Rotation Curves

Equilibrium of a gravitating scalar field inside a black hole compressed to the state of a boson matter, in balance with a longitudinal vector field (dark matter) from outside is considered. Analytical consideration, confirmed numerically, shows that there exist static solutions of Einstein’s equations with arbitrary high total mass of a black hole, where the component of the metric tensor [Formula: see text] changes its sign twice. The balance of the energy-momentum tensors of the scalar field and the longitudinal vector field at the interface ensures the equilibrium of these phases. Considering a gravitating scalar field as an example, the internal structure of a black hole is revealed. Its phase equilibrium with the longitudinal vector field, describing dark matter on the periphery of a galaxy, determines the dependence of the velocity on the plateau of galaxy rotation curves on the mass of a black hole, located in the center of a galaxy.

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The Substellar Members of the Pleiades

Symposium - International Astronomical Union ◽

10.1017/s007418090021053x ◽

2003 ◽

Vol 211 ◽

pp. 181-182

Author(s):

Paul D. Dobbie ◽

Richard F. Jameson ◽

Samantha L. Osborne ◽

Simon T. Hodgkin ◽

David J. Pinfield

Keyword(s):

Dark Matter ◽

Spatial Distribution ◽

Power Law ◽

Spatial Model ◽

Total Mass ◽

Brown Dwarfs ◽

Mass Function ◽

Core Radius ◽

Brown Dwarf ◽

Limited Sample

We have compiled the largest magnitude limited sample of candidate substellar Pleiads to date. We fit King profiles to their spatial distribution to determine the Pleiades brown dwarf core radius to be Subsequently we have used our improved spatial model to place stringent limits on the shape of the cluster mass function across and below the stellar/substellar regime. We find this to be a power law with index α = 0.41±0.08 (0.3M⊙ ≥M≥ 0.035M⊙). Extrapolation of this mass function to M= 0.012M⊙ indicates that brown dwarfs contribute only ~ 2% to the total mass of the cluster hence we conclude that brown dwarfs do not contribute significantly to disk dark matter.

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DARK MATTER AND DYNAMICS IN HERCULES CLUSTER

International Journal of Modern Physics D ◽

10.1142/s021827189400099x ◽

1994 ◽

Vol 03 (supp01) ◽

pp. 93-100

Author(s):

Christina M. Bird ◽

John M. Dickey ◽

E.E. Salpeter

Keyword(s):

Dark Matter ◽

Total Mass ◽

Virial Theorem ◽

Spiral Galaxies ◽

Large Body ◽

Statistical Test ◽

Mass Determination ◽

Dynamical Mass ◽

Cluster Galaxies ◽

Abell Cluster

We present new 21-cm observations of faint (15.7<mpg<16.5) spiral galaxies in the Abell cluster 2151. These results, when combined with the large body of velocities available in the literature for Hercules, permit us to study the dynamics throughout the cluster core, out to a projected radius of 1.8h−1 Mpc. We calculate the global dynamical mass of Hercules using 3 different but related methods: two versions of the virial theorem and the projected mass estimator. These masses lie in the range 3–6×1014 M⊙. We investigate the importance of subclustering in A2151 using the statistical test of Dressler and Shectman1 and the effects of the detected substructure on the dynamical mass determination. The clumpy distribution of galaxies is interpreted as a sign that the galaxies in the cluster have not reached dynamical equilibrium in the gravitational potential, which means that dynamical mass estimates are prone to significant errors. In spite of this uncertainty, we estimate that the virial theorem errors due to the presence of substructure are not larger than 30% in A2151. Finally, we use the 21-cm linewidths to estimate the minimum total mass in the cluster which is contained within the HI radii of the cluster galaxies is about 3×1014 M⊙. This number may be compared with the dynamical mass and used to separate the contribution of dark matter inside and outside the HI envelopes of galaxies, and the fraction of DM which cannot be associated with individual galaxies, about 90–95%.

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The Most Massive galaxy Clusters (M2C) across cosmic time: link between radial total mass distribution and dynamical state

Astronomy and Astrophysics ◽

10.1051/0004-6361/201935984 ◽

2019 ◽

Vol 628 ◽

pp. A86 ◽

Cited By ~ 4

Author(s):

I. Bartalucci ◽

M. Arnaud ◽

G. W. Pratt ◽

J. Démoclès ◽

L. Lovisari

Keyword(s):

Total Mass ◽

Large Scale ◽

Cosmic Time ◽

High Mass ◽

Shift Parameter ◽

Dynamical State ◽

Centroid Shift ◽

Mass Profile ◽

The One ◽

Mass Profiles

We study the dynamical state and the integrated total mass profiles of 75 massive (M500 > 5 × 1014 M⊙) Sunyaev–Zeldovich(SZ)-selected clusters at 0.08 < z < 1.1. The sample is built from the Planck catalogue, with the addition of four SPT clusters at z > 0.9. Using XMM-Newton imaging observations, we characterise the dynamical state with the centroid shift ⟨w⟩, the concentration CSB, and their combination, M, which simultaneously probes the core and the large-scale gas morphology. Using spatially resolved spectroscopy and assuming hydrostatic equilibrium, we derive the total integrated mass profiles. The mass profile shape is quantified by the sparsity, that is the ratio of M500 to M2500, the masses at density contrasts of 500 and 2500, respectively. We study the correlations between the various parameters and their dependence on redshift. We confirm that SZ-selected samples, thought to most accurately reflect the underlying cluster population, are dominated by disturbed and non-cool core objects at all redshifts. There is no significant evolution or mass dependence of either the cool core fraction or the centroid shift parameter. The M parameter evolves slightly with z, having a correlation coefficient of ρ = −0.2 ± 0.1 and a null hypothesis p-value of 0.01. In the high-mass regime considered here, the sparsity evolves minimally with redshift, increasing by 10% between z < 0.2 and z > 0.55, an effect that is significant at less than 2σ. In contrast, the dependence of the sparsity on dynamical state is much stronger, increasing by a factor of ∼60% from the one third most relaxed to the one third most disturbed objects, an effect that is significant at more than 3σ. This is the first observational evidence that the shape of the integrated total mass profile in massive clusters is principally governed by the dynamical state and is only mildly dependent on redshift. We discuss the consequences for the comparison between observations and theoretical predictions.

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Constraining the abundance of dark matter in the central region of the galaxy cluster MACS J1206.2−0847 with a free-form strong lensing analysis

Astronomy and Astrophysics ◽

10.1051/0004-6361/201936914 ◽

2020 ◽

Vol 639 ◽

pp. A125

Author(s):

Alberto Manjón-García ◽

Jose M. Diego ◽

Diego Herranz ◽

Daniel Lam

Keyword(s):

Dark Matter ◽

Mass Distribution ◽

Central Region ◽

Total Mass ◽

Galaxy Cluster ◽

Free Form ◽

Matter Distribution ◽

Strong Lensing ◽

The Galaxy ◽

Dark Matter Distribution

We performed a free-form strong lensing analysis of the galaxy cluster MACS J1206.2−0847 in order to estimate and constrain its inner dark matter distribution. The free-form method estimates the cluster total mass distribution without using any prior information about the underlying mass. We used 97 multiple lensed images belonging to 27 background sources and derived several models, which are consistent with the data. Among these models, we focus on those that better reproduce the radial images that are closest to the centre of the cluster. These radial images are the best probes of the dark matter distribution in the central region and constrain the mass distribution down to distances ∼7 kpc from the centre. We find that the morphology of the innermost radial arcs is due to the elongated morphology of the dark matter halo. We estimate the stellar mass contribution of the brightest cluster galaxy and subtracted it from the total mass in order to quantify the amount of dark matter in the central region. We fitted the derived dark matter density profile with a gNFW, which is characterised by rs = 167 kpc, ρs = 6.7 × 106 M⊙ kpc−3, and γgNFW = 0.70. These results are consistent with a dynamically relaxed cluster. This inner slope is smaller than the cannonical γ = 1 predicted by standard CDM models. This slope does not favour self-interacting models for which a shallower slope would be expected.

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CDM in LSB Galaxies: Toward the Optimal Halo Profile

Symposium - International Astronomical Union ◽

10.1017/s0074180900182890 ◽

2004 ◽

Vol 220 ◽

pp. 69-76 ◽

Cited By ~ 1

Author(s):

W. J. G de Blok

Keyword(s):

Dark Matter ◽

Total Mass ◽

Surface Brightness ◽

Cold Dark Matter ◽

Mass Density ◽

Constant Density ◽

Adequate Description ◽

Density Distributions ◽

Low Surface Brightness ◽

Lsb Galaxies

Low Surface Brightness (LSB) galaxies are dominated by dark matter. High-resolution rotation curves suggest that their total mass-density distributions are dominated by constant density cores rather than the steep and cuspy distributions found in Cold Dark Matter (CDM) simulations. the data are best described by a model with a soft core with an inner power-law mass-density slope α = 0.2 ± 0.2. However no single universal halo profile provides an adequate description of the data. the observed mass profiles appear to be inconsistent with ACDM.

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Testing Modified Dark Matter with galaxy clusters: Does dark matter know about the cosmological constant?

International Journal of Modern Physics A ◽

10.1142/s0217751x17501081 ◽

2017 ◽

Vol 32 (18) ◽

pp. 1750108 ◽

Cited By ~ 9

Author(s):

Douglas Edmonds ◽

Duncan Farrah ◽

Chiu Man Ho ◽

Djordje Minic ◽

Y. Jack Ng ◽

...

Keyword(s):

Dark Matter ◽

Cosmological Constant ◽

Galaxy Clusters ◽

Cold Dark Matter ◽

Galactic Rotation ◽

Dark Matter Mass ◽

Mass Profile ◽

The One ◽

Gravitational Thermodynamics ◽

Mass Profiles

We discuss the possibility that the cold dark matter mass profiles contain information on the cosmological constant [Formula: see text], and that such information constrains the nature of cold dark matter (CDM). We call this approach Modified Dark Matter (MDM). In particular, we examine the ability of MDM to explain the observed mass profiles of 13 galaxy clusters. Using general arguments from gravitational thermodynamics, we provide a theoretical justification for our MDM mass profile. In order to properly fit the shape of the mass profiles in galaxy clusters, we find it necessary to generalize the MDM mass profile from the one we used previously to fit galactic rotation curves. We successfully compare it to the NFW mass profiles both on cluster and galactic scales, though differences in form appear with the change in scales. Our results suggest that indeed the CDM mass profiles contain information about the cosmological constant in a nontrivial way.

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