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Related papers: The squeezed matter bispectrum covariance with res…

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We present a calculation of the matter power spectrum covariance matrix ${\rm Cov}(\bf{k}_1,\bf{k}_2)$ that uses power spectrum responses to accurately describe the coupling between large- and small-scale modes beyond the perturbative…

Cosmology and Nongalactic Astrophysics · Physics 2017-12-13 Alexandre Barreira , Fabian Schmidt

We introduce a rigorous definition of general power-spectrum responses as resummed vertices with two hard and $n$ soft momenta in cosmological perturbation theory. These responses measure the impact of long-wavelength perturbations on the…

Cosmology and Nongalactic Astrophysics · Physics 2017-11-03 Alexandre Barreira , Fabian Schmidt

We present a model for the squeezed dark matter bispectrum, where the short modes are deep in the non-linear regime. We exploit the consistency relations for large-scale structures combined with a response function approach to write the…

Cosmology and Nongalactic Astrophysics · Physics 2023-09-14 Matteo Biagetti , Juan Calles , Lina Castiblanco , Katherine González , Jorge Noreña

We show that in a certain, angle-averaged squeezed limit, the $N$-point function of matter is related to the response of the matter power spectrum to a long-wavelength density perturbation,…

Cosmology and Nongalactic Astrophysics · Physics 2015-09-09 Christian Wagner , Fabian Schmidt , Chi-Ting Chiang , Eiichiro Komatsu

The influence of large-scale density fluctuations on structure formation on small scales is described by the three-point correlation function (bispectrum) in the so-called "squeezed configurations," in which one wavenumber, say $k_3$, is…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-19 Chi-Ting Chiang , Christian Wagner , Fabian Schmidt , Eiichiro Komatsu

We provide an analytical description of the galaxy bispectrum covariance and the power spectrum-bispectrum cross-covariance in redshift space that captures the dominant non-Gaussian contributions. The Gaussian prediction for the variance of…

Cosmology and Nongalactic Astrophysics · Physics 2024-03-14 Jacopo Salvalaggio , Lina Castiblanco , Jorge Noreña , Emiliano Sefusatti , Pierluigi Monaco

We measure the halo bispectrum covariance in a large set of N-body simulations and compare it with theoretical expectations. We find a large correlation among (even mildly) squeezed halo bispectrum configurations. A similarly large…

Cosmology and Nongalactic Astrophysics · Physics 2022-09-14 Matteo Biagetti , Lina Castiblanco , Jorge Noreña , Emiliano Sefusatti

We derive in this paper expressions for the covariance matrix of the cosmic shear two-point correlation functions which are readily applied to any survey geometry. Furthermore, we consider the more special case of a simple survey geometry…

Astrophysics · Physics 2009-11-07 Peter Schneider , Ludovic van Waerbeke , Martin Kilbinger , Yannick Mellier

We present a method to estimate non-Gaussian power spectrum covariance matrices by directly measuring the response of the small-scale power spectrum to long-wavelength perturbations via bispectrum and trispectrum estimators. Specifically,…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-21 Samuel Goldstein , Kendrick M. Smith , Utkarsh Giri , Moritz Münchmeyer

Modes with wavelengths larger than the survey window can have significant impact on the covariance within the survey window. The supersample covariance has been recognized as an important source of covariance for the power spectrum on small…

Cosmology and Nongalactic Astrophysics · Physics 2018-03-07 Kwan Chuen Chan , Azadeh Moradinezhad Dizgah , Jorge Noreña

The covariance matrix of the matter and halo power spectrum and bispectrum are studied. Using a large suite of simulations, we find that the non-Gaussianity in the covariance is significant already at mildly nonlinear scales. We compute the…

Cosmology and Nongalactic Astrophysics · Physics 2017-07-26 Kwan Chuen Chan , Linda Blot

We derive the complete super-sample covariance (SSC) of the matter and weak lensing convergence power spectra using the power spectrum response formalism to accurately describe the coupling of super- to sub-survey modes. The SSC term is…

Cosmology and Nongalactic Astrophysics · Physics 2018-06-27 Alexandre Barreira , Elisabeth Krause , Fabian Schmidt

The squeezed-limit bispectrum, which is generated by nonlinear gravitational evolution as well as inflationary physics, measures the correlation of three wavenumbers, in the configuration where one wavenumber is much smaller than the other…

Cosmology and Nongalactic Astrophysics · Physics 2017-06-28 Chi-Ting Chiang , Agnieszka M. Cieplak , Fabian Schmidt , Anže Slosar

Modeling the nonlinearity of the halo bispectrum remains a major challenge in modern cosmology, in particular for ongoing and upcoming large-scale structure observations that are performed to study the inflationary physics. The "power…

Cosmology and Nongalactic Astrophysics · Physics 2017-06-21 Chi-Ting Chiang

To investigate and specify the statistical properties of cosmological fields with particular attention to possible non-Gaussian features, accurate formulae for the bispectrum and the bispectrum covariance are required. The bispectrum is the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Sandra Martin , Peter Schneider , Patrick Simon

We present a new observable, position-dependent power spectrum, to measure the large-scale structure bispectrum in the squeezed configuration, where one wavenumber is much smaller than the other two. The squeezed-limit bispectrum measures…

Cosmology and Nongalactic Astrophysics · Physics 2015-08-14 Chi-Ting Chiang

In this study, we measure the response of matter and halo projected power spectra $P^{\rm 2D}_{\rm XY}(k)$ (X, Y are matter and/or halos), to a large-scale density contrast, $\delta_{\rm b}$, using separate universe simulations. We show…

Cosmology and Nongalactic Astrophysics · Physics 2018-11-14 Ryuichi Takahashi , Takahiro Nishimichi , Masahiro Takada , Masato Shirasaki , Kosei Shiroyama

Using separate universe simulations, we accurately quantify super-sample covariance (SSC), the typically dominant sampling error for matter power spectrum estimators in a finite volume, which arises from the presence of super survey modes.…

Cosmology and Nongalactic Astrophysics · Physics 2014-04-28 Yin Li , Wayne Hu , Masahiro Takada

We consider nonlinear biasing models of galaxies with particular attention to a correlation between linear and quadratic biasing coefficients, b_1 and b_2. We first derive perturbative expressions for b_1 and b_2 in halo and peak biasing…

Upcoming surveys of cosmic structures will probe scales close to the cosmological horizon, which opens up new opportunities for testing the cosmological concordance model to high accuracy. In particular, constraints on the squeezed…

Cosmology and Nongalactic Astrophysics · Physics 2023-08-28 Thomas Montandon , Julian Adamek , Oliver Hahn , Jorge Noreña , Cornelius Rampf , Clément Stahl , Bartjan van Tent
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