Cosmological constraints from the large-scale weak lensing of SDSS MaxBCG clusters

We reanalyse the anisotropic galaxy clustering measurement from the Baryon Oscillation Spectroscopic Survey (BOSS), demonstrating that using the full shape information provides cosmological constraints that are comparable to other low-redshift probes. We find Ωm = 0.317+0.015−0.019, σ8 = 0.710±0.049, and h = 0.704 ± 0.024 for flat ΛCDM cosmologies using uninformative priors on Ωch2, 100θMC, ln1010As, and ns, and a prior on Ωbh2 that is much wider than current constraints. We quantify the agreement between the Planck 2018 constraints from the cosmic microwave background and BOSS, finding the two data sets to be consistent within a flat ΛCDM cosmology using the Bayes factor as well as the prior-insensitive suspiciousness statistic. Combining two low-redshift probes, we jointly analyse the clustering of BOSS galaxies with weak lensing measurements from the Kilo-Degree Survey (KV450). The combination of BOSS and KV450 improves the measurement by up to 45%, constraining σ8 = 0.702 ± 0.029 and S8 = σ8 Ωm/0.3 = 0.728 ± 0.026. Over the full 5D parameter space, the odds in favour of a single cosmology describing galaxy clustering, lensing, and the cosmic microwave background are 7 ± 2. The suspiciousness statistic signals a 2.1 ± 0.3σ tension between the combined low-redshift probes and measurements from the cosmic microwave background.

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Weak Lensing by Large‐Scale Structure with the FIRST Radio Survey

The Astrophysical Journal ◽

10.1086/425491 ◽

2004 ◽

Vol 617 (2) ◽

pp. 794-810 ◽

Cited By ~ 47

Author(s):

Tzu‐Ching Chang ◽

Alexandre Refregier ◽

David J. Helfand

Keyword(s):

Large Scale ◽

Large Scale Structure ◽

Scale Structure ◽

Weak Lensing ◽

Radio Survey

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Exact joint likelihood of pseudo-Cℓ estimates from correlated Gaussian cosmological fields

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stz3225 ◽

2019 ◽

Vol 491 (3) ◽

pp. 3165-3181 ◽

Cited By ~ 1

Author(s):

Robin E Upham ◽

Lee Whittaker ◽

Michael L Brown

Keyword(s):

Quadratic Form ◽

Power Spectrum ◽

Quadratic Forms ◽

Joint Distribution ◽

Large Scale ◽

Power Spectra ◽

Microwave Background ◽

Cosmological Constraints ◽

Statistical Precision ◽

Joint Likelihood

ABSTRACT We present the exact joint likelihood of pseudo-Cℓ power spectrum estimates measured from an arbitrary number of Gaussian cosmological fields. Our method is applicable to both spin-0 fields and spin-2 fields, including a mixture of the two, and is relevant to cosmic microwave background (CMB), weak lensing, and galaxy clustering analyses. We show that Gaussian cosmological fields are mixed by a mask in such a way that retains their Gaussianity and derive exact expressions for the covariance of the cut-sky spherical harmonic coefficients, the pseudo-aℓms, without making any assumptions about the mask geometry. We then show that each auto or cross-pseudo-Cℓ estimator can be written as a quadratic form, and apply the known joint distribution of quadratic forms to obtain the exact joint likelihood of a set of pseudo-Cℓ estimates in the presence of an arbitrary mask. We show that the same formalism can be applied to obtain the exact joint likelihood of quadratic maximum likelihood power spectrum estimates. Considering the polarization of the CMB as an example, we show using simulations that our likelihood recovers the full, exact multivariate distribution of EE, BB, and EB pseudo-Cℓ power spectra. Our method provides a route to robust cosmological constraints from future CMB and large-scale structure surveys in an era of ever-increasing statistical precision.

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Forecasting cosmological constraints from the weak lensing magnification of type Ia supernovae measured by the Nancy Grace Roman Space Telescope

Physical Review D ◽

10.1103/physrevd.102.123513 ◽

2020 ◽

Vol 102 (12) ◽

Author(s):

Zhongxu Zhai ◽

Yun Wang ◽

Dan Scolnic

Keyword(s):

Weak Lensing ◽

Type Ia Supernovae ◽

Space Telescope ◽

Cosmological Constraints ◽

Type Ia ◽

Ia Supernovae

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Testing the reliability of fast methods for weak lensing simulations: wl-moka on pinocchio

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa1538 ◽

2020 ◽

Vol 496 (2) ◽

pp. 1307-1324

Author(s):

Carlo Giocoli ◽

Pierluigi Monaco ◽

Lauro Moscardini ◽

Tiago Castro ◽

Massimo Meneghetti ◽

...

Keyword(s):

Large Scale ◽

Initial Conditions ◽

Mass Density ◽

Cosmological Parameters ◽

Power Spectra ◽

Mass Function ◽

Parametric Models ◽

Weak Lensing ◽

Approximate Methods ◽

Percent Accuracy

ABSTRACT The generation of simulated convergence maps is of key importance in fully exploiting weak lensing by large-scale structure (LSS) from which cosmological parameters can be derived. In this paper, we present an extension of the pinocchio code that produces catalogues of dark matter haloes so that it is capable of simulating weak lensing by Modify LSS into Large Scale Structures (LSS). Like wl-moka, the method starts with a random realization of cosmological initial conditions, creates a halo catalogue and projects it on to the past light-cone, and paints in haloes assuming parametric models for the mass density distribution within them. Large-scale modes that are not accounted for by the haloes are constructed using linear theory. We discuss the systematic errors affecting the convergence power spectra when Lagrangian perturbation theory at increasing order is used to displace the haloes within pinocchio, and how they depend on the grid resolution. Our approximate method is shown to be very fast when compared to full ray-tracing simulations from an N-body run and able to recover the weak lensing signal, at different redshifts, with a few percent accuracy. It also allows for quickly constructing weak lensing covariance matrices, complementing pinocchio’s ability of generating the cluster mass function and galaxy clustering covariances and thus paving the way for calculating cross-covariances between the different probes. This work advances these approximate methods as tools for simulating and analysing survey data for cosmological purposes.

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