Combining Probes

AbstractWith the advent of wide-field surveys, cosmology has entered a new golden age of data where our cosmological model and the nature of dark universe will be tested with unprecedented accuracy, so that we can strive for high precision cosmology. Observational probes like weak lensing, galaxy surveys and the cosmic microwave background as well as other observations will all contribute to these advances. These different probes trace the underlying expansion history and growth of structure in complementary ways and can be combined in order to extract cosmological parameters as best as possible. With future wide-field surveys, observational overlap means these will trace the same physical underlying dark matter distribution, and extra care must be taken when combining information from different probes. Consideration of probe combination is a fundamental aspect of cosmostatistics and important to ensure optimal use of future wide-field surveys.

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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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On the Cross‐Correlation between Dark Matter Distribution and Secondary Cosmic Microwave Background Anisotropies of the Ionized Intergalactic Medium

The Astrophysical Journal ◽

10.1086/339173 ◽

2002 ◽

Vol 569 (1) ◽

pp. 8-17 ◽

Cited By ~ 2

Author(s):

Masahiro Takada ◽

Naoshi Sugiyama

Keyword(s):

Dark Matter ◽

Cosmic Microwave Background ◽

Cross Correlation ◽

Intergalactic Medium ◽

Matter Distribution ◽

Microwave Background ◽

Dark Matter Distribution ◽

The Cross ◽

Microwave Background Anisotropies

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Probing the Origins of Voids in the Distribution of Galaxies

Publications of the Astronomical Society of Australia ◽

10.1071/as04079 ◽

2005 ◽

Vol 22 (2) ◽

pp. 166-173 ◽

Cited By ~ 1

Author(s):

Louise M. Ord ◽

Martin Kunz ◽

Hugues Mathis ◽

Joseph Silk

Keyword(s):

Dark Matter ◽

Cold Dark Matter ◽

External Source ◽

Scientific Meeting ◽

Acoustic Oscillations ◽

De Sitter ◽

Matter Distribution ◽

Microwave Background ◽

Sitter Background ◽

Dark Matter Distribution

AbstractIf the voids that we see today in the distribution of galaxies existed at recombination, they will leave an imprint on the cosmic microwave background (CMB). On the other hand, if these voids formed much later, their effect on the CMB will be negligible and will not be observed with the current generation of experiments. In this paper, presented at the 2004 Annual Scientific Meeting of the Astronomical Society of Australia, we discuss our ongoing investigations into voids of primordial origin. We show that if voids in the cold dark matter distribution existed at the epoch of decoupling, they could contribute significantly to the apparent rise in CMB power on small scales detected by the Cosmic Background Imager (CBI) Deep Field. Here we present our improved method for predicting the effects of primordial voids on the CMB in which we treat a void as an external source in the cold dark matter (CDM) distribution employing a Boltzmann solver. Our improved predictions include the effects of a cosmological constant (Λ) and acoustic oscillations generated by voids at early times. We find that models with relatively large voids on the last scattering surface predict too much CMB power in an Einstein–de Sitter background cosmology but could be consistent with the current CMB observations in a ΛCDM universe.

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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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3 per cent-accurate predictions for the clustering of dark matter, haloes, and subhaloes, over a wide range of cosmologies and scales

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa3117 ◽

2020 ◽

Vol 499 (4) ◽

pp. 4905-4917

Author(s):

S Contreras ◽

R E Angulo ◽

M Zennaro ◽

G Aricò ◽

M Pellejero-Ibañez

Keyword(s):

Dark Matter ◽

Spatial Distribution ◽

Cosmological Parameters ◽

Galaxy Surveys ◽

Circular Velocity ◽

Initial Application ◽

Wide Range ◽

Massive Neutrinos ◽

Dynamical Dark Energy ◽

Better Than

ABSTRACT Predicting the spatial distribution of objects as a function of cosmology is an essential ingredient for the exploitation of future galaxy surveys. In this paper, we show that a specially designed suite of gravity-only simulations together with cosmology-rescaling algorithms can provide the clustering of dark matter, haloes, and subhaloes with high precision. Specifically, with only three N-body simulations, we obtain the power spectrum of dark matter at z = 0 and 1 to better than 3 per cent precision for essentially all currently viable values of eight cosmological parameters, including massive neutrinos and dynamical dark energy, and over the whole range of scales explored, 0.03 < $k/{h}^{-1}\, {\rm Mpc}^{-1}$ < 5. This precision holds at the same level for mass-selected haloes and for subhaloes selected according to their peak maximum circular velocity. As an initial application of these predictions, we successfully constrain Ωm, σ8, and the scatter in subhalo-abundance-matching employing the projected correlation function of mock SDSS galaxies.

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