Shapley supercluster survey: mapping the dark matter distribution

ABSTRACT We present a 23 deg2 weak gravitational lensing survey of the Shapley supercluster core and its surroundings using gri VST images as part of the Shapley Supercluster Survey (ShaSS). This study reveals the overall matter distribution over a region containing 11 clusters at z ∼ 0.048 that are all interconnected, as well as several ongoing cluster–cluster interactions. Galaxy shapes have been measured by using the Kaiser–Squires–Broadhurst method for the g- and r-band images and background galaxies were selected via the gri colour–colour diagram. This technique has allowed us to detect all of the clusters, either in the g- or r-band images, although at different σ levels, indicating that the underlying dark matter distribution is tightly correlated with the number density of the member galaxies. The deeper r-band images have traced the five interacting clusters in the supercluster core as a single coherent structure, confirmed the presence of a filament extending North from the core, and have revealed a background cluster at z ∼ 0.17. We have measured the masses of the four richest clusters (A3556, A3558, A3560, and A3562) in the two-dimensional shear pattern, assuming a spherical Navarro–Frenk–White profile and obtaining a total mass of $\mathcal {M}_{\rm ShaSS,WL}{=}1.56^{+0.81}_{-0.55}{\times }10^{15\, }{\rm M}_{\odot }$, which is consistent with dynamical and X-ray studies. Our analysis provides further evidence of the ongoing dynamical evolution in the ShaSS region.

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Observable tests of self-interacting dark matter in galaxy clusters: cosmological simulations with SIDM and baryons

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stz1815 ◽

2019 ◽

Vol 488 (3) ◽

pp. 3646-3662 ◽

Cited By ~ 14

Author(s):

Andrew Robertson ◽

David Harvey ◽

Richard Massey ◽

Vincent Eke ◽

Ian G McCarthy ◽

...

Keyword(s):

Dark Matter ◽

Galaxy Clusters ◽

Gravitational Lensing ◽

Interaction Strength ◽

Matter Distribution ◽

Cosmological Simulations ◽

X Ray ◽

Critical Curves ◽

Strong Lensing ◽

Dark Matter Distribution

ABSTRACT We present bahamas-SIDM, the first large-volume, $(400 \, h^{-1} \mathrm{\, Mpc})^{3}$, cosmological simulations including both self-interacting dark matter (SIDM) and baryonic physics. These simulations are important for two primary reasons: (1) they include the effects of baryons on the dark matter distribution and (2) the baryon particles can be used to make mock observables that can be compared directly with observations. As is well known, SIDM haloes are systematically less dense in their centres, and rounder, than CDM haloes. Here, we find that that these changes are not reflected in the distribution of gas or stars within galaxy clusters, or in their X-ray luminosities. However, gravitational lensing observables can discriminate between DM models, and we present a menu of tests that future surveys could use to measure the SIDM interaction strength. We ray-trace our simulated galaxy clusters to produce strong lensing maps. Including baryons boosts the lensing strength of clusters that produce no critical curves in SIDM-only simulations. Comparing the Einstein radii of our simulated clusters with those observed in the CLASH survey, we find that at velocities around $1000 \mathrm{\, km \, s^{-1}}$ an SIDM cross-section of $\sigma /m \gtrsim 1 \, \mathrm{cm^2 \, g^{-1}}$ is likely incompatible with observed cluster lensing.

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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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Inner dark matter distribution of the Cosmic Horseshoe (J1148+1930) with gravitational lensing and dynamics

Astronomy and Astrophysics ◽

10.1051/0004-6361/201935042 ◽

2019 ◽

Vol 631 ◽

pp. A40 ◽

Cited By ~ 4

Author(s):

S. Schuldt ◽

G. Chirivì ◽

S. H. Suyu ◽

A. Yıldırım ◽

A. Sonnenfeld ◽

...

Keyword(s):

Dark Matter ◽

Gravitational Lensing ◽

Gravitational Lens ◽

Wide Field ◽

Lens System ◽

Matter Distribution ◽

Mass Model ◽

Luminous Matter ◽

Dark Matter Distribution ◽

Light Components

We present a detailed analysis of the inner mass structure of the Cosmic Horseshoe (J1148+1930) strong gravitational lens system observed with the Hubble Space Telescope (HST) Wide Field Camera 3 (WFC3). In addition to the spectacular Einstein ring, this systems shows a radial arc. We obtained the redshift of the radial arc counterimage zs, r = 1.961 ± 0.001 from Gemini observations. To disentangle the dark and luminous matter, we considered three different profiles for the dark matter (DM) distribution: a power law profile, the Navarro, Frenk, and White (NFW) profile, and a generalized version of the NFW profile. For the luminous matter distribution, we based the model on the observed light distribution that is fitted with three components: a point mass for the central light component resembling an active galactic nucleus, and the remaining two extended light components scaled by a constant mass-to-light ratio (M/L). To constrain the model further, we included published velocity dispersion measurements of the lens galaxy and performed a self-consistent lensing and axisymmetric Jeans dynamical modeling. Our model fits well to the observations including the radial arc, independent of the DM profile. Depending on the DM profile, we get a DM fraction between 60% and 70%. With our composite mass model we find that the radial arc helps to constrain the inner DM distribution of the Cosmic Horseshoe independently of the DM profile.

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Cores vs. Cusps: Dark Matter Density Profiles in Spirals

Symposium - International Astronomical Union ◽

10.1017/s0074180900183469 ◽

2004 ◽

Vol 220 ◽

pp. 311-312

Author(s):

Gianfranco Gentile ◽

Uli Klein ◽

Paolo Salucci ◽

Daniela Vergani

Keyword(s):

Dark Matter ◽

Rotation Curve ◽

Spiral Galaxies ◽

Matter Density ◽

Matter Distribution ◽

Rotation Curves ◽

Density Profiles ◽

The Core ◽

Dark Matter Distribution ◽

A New Technique

We use photometric, Hα and Hi data to investigate the distribution of dark matter in spiral galaxies. A new technique for deriving the Hi rotation curve is presented. the final combined Hα+Hi rotation curves are symmetric, well resolved and extend to large radii. We perform the rotation curve decomposition into the luminous and dark matter contributions. the observations are confronted with different models of the dark matter distribution, including core-dominated and cusp-dominated halos as well as less conventional possibilities. the best agreement with the observations is found for the core-dominated halos.

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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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Dark matter and X-ray halo in early-type galaxies and clusters of galaxies

Proceedings of the International Astronomical Union ◽

10.1017/s1743921310008422 ◽

2009 ◽

Vol 5 (H15) ◽

pp. 89-90

Author(s):

Takaya Ohashi

Keyword(s):

Dark Matter ◽

Clusters Of Galaxies ◽

Large Scatter ◽

Early Type ◽

Matter Distribution ◽

X Ray ◽

Galaxy Groups ◽

Hot Gas ◽

Luminous Galaxies ◽

Dark Matter Distribution

X-ray observations reveal extended halos around early-type galaxies which enable us to trace the dark matter distribution around the galaxies (see Mathews and Brighenti 2003 for a review). X-ray luminosities, LX of massive early-type galaxies are 1040−1042 erg s−1 in 0.3–2 keV. The correlation plot between LX and B-band luminosity LB shows a large scatter in the sense that LX varies by 2 orders of magnitudes for the same LB, in the brightest end (log LB ≳ 10.5). The amount of the X-ray hot gas in early-type galaxies is typically a few % of the stellar mass, in contrast to clusters of galaxies which hold ~5 times more massive gas than stars. Matsushita (2001) showed that X-ray luminous galaxies are characterized by extended X-ray halo with a few tens of re, similar to the scale of galaxy groups, so the presence of group-size potentials would be strongly linked with the problem of large LX scatter.

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Dark Matter Distribution in X-Ray Clusters of Galaxies

Cosmological Aspects of X-Ray Clusters of Galaxies ◽

10.1007/978-94-011-1022-8_12 ◽

1994 ◽

pp. 107-111

Author(s):

Florence Durret ◽

D. Gerbal ◽

M. Lachièze-Rey ◽

G. Lima-Neto ◽

R. Sadat

Keyword(s):

Dark Matter ◽

Clusters Of Galaxies ◽

Matter Distribution ◽

X Ray ◽

Dark Matter Distribution

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X-ray measurements of the dark matter distribution in clusters of galaxies with Chandra

Advances in Space Research ◽

10.1016/j.asr.2003.06.045 ◽

2004 ◽

Vol 34 (12) ◽

pp. 2519-2524 ◽

Cited By ~ 6

Author(s):

H. Katayama ◽

K. Hayashida

Keyword(s):

Dark Matter ◽

Clusters Of Galaxies ◽

Matter Distribution ◽

X Ray ◽

Dark Matter Distribution

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Effects of non-vanishing dark matter pressure in the Milky Way Galaxy

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stab2571 ◽

2021 ◽

Vol 508 (1) ◽

pp. 1543-1554

Author(s):

K Boshkayev ◽

T Konysbayev ◽

E Kurmanov ◽

O Luongo ◽

D Malafarina ◽

...

Keyword(s):

Black Hole ◽

Dark Matter ◽

Gravitational Lensing ◽

Matter Content ◽

Dark Matter Halo ◽

Matter Distribution ◽

Milky Way Galaxy ◽

The Galaxy ◽

Dark Matter Distribution ◽

Inner Parts

ABSTRACT We consider the possibility that the Milky Way’s dark matter halo possesses a non-vanishing equation of state. Consequently, we evaluate the contribution due to the speed of sound, assuming that the dark matter content of the galaxy behaves like a fluid with pressure. In particular, we model the dark matter distribution via an exponential sphere profile in the galactic core, and inner parts of the galaxy whereas we compare the exponential sphere with three widely used profiles for the halo, i.e. the Einasto, Burkert and Isothermal profile. For the galactic core, we also compare the effects due to a dark matter distribution without black hole with the case of a supermassive black hole in vacuum and show that present observations are unable to distinguish them. Finally we investigate the expected experimental signature provided by gravitational lensing due to the presence of dark matter in the core.

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