Article
Astronomy & Astrophysics
Andrei Lazanu
Summary: Machine learning techniques accurately extract cosmological parameters Omega(m) and sigma(8) from N-body simulations, and also find these parameters from the non-linear matter power spectrum using random forest regressors and deep neural networks. The power spectrum provides competitive results in terms of accuracy compared to using simulations, and the scalar spectral index ns can also be estimated from the power spectrum with lower precision.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
Guido D'Amico, Leonardo Senatore, Pierre Zhang
Summary: By applying the Effective Field Theory of Large-Scale Structure to analyze the wCDM cosmological model, competitive CMB-independent limits on parameter w were set using data from BOSS, Pantheon, and BBN. After incorporating the Planck CMB data, adjustments were made to the limits on parameter w.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
Rebeca Martinez-Carrillo, Juan Carlos Hidalgo, Karim A. Malik, Alkistis Pourtsidou
Summary: The researchers compute the real space galaxy power spectrum, including the effects of General Relativity and primordial non-Gaussianity through parameters f(NL) and g(NL), and assess the detectability of these contributions in Stage-IV surveys. They also found that specific values of the bias parameter may erase the primordial and relativistic contributions to the configuration space power spectrum.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
Anton Baleato Lizancos, Martin White
Summary: A leading method to constrain physical theories from cosmological observations is to test their predictions for the angular clustering statistics of matter tracers. This article explores the impact of anisotropies in the redshift distribution on angular two-point statistics, identifying a mode-coupling effect that adds power to auto-correlations and removes it from certain cross-correlations. The study also discusses special cases like galaxy clustering and cosmic shear and releases a code to compute the biases.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2023)
Article
Astronomy & Astrophysics
Florian Beutler, Patrick McDonald
Summary: Recent developments in galaxy redshift surveys have led to the proposal of a matrix-based analysis framework for galaxy power spectrum multipoles, providing deconvolved power spectrum results for several datasets. The use of deconvolved power spectrum multipoles allows for a data analysis independent of survey-specific aspects, such as the window function. This alternative analysis method has been shown to yield similar results to standard analysis in the case of the BOSS dataset, with various analysis components and a Python toolbox provided for convenience.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
Fabian Schmidt
Summary: A forward model for matter and biased tracers at arbitrary order in Lagrangian perturbation theory is introduced, including complete LPT displacement field and relevant bias operators. Validation tests show subpercent agreement with N-body simulations, demonstrating the effectiveness and accuracy of the model. This method has broad applications in cosmology research.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
Theo Simon, Pierre Zhang, Vivian Poulin
Summary: This study presents cosmological results obtained from analyzing the power spectrum of eBOSS quasars using effective-field theory (EFT). The analysis provides constraints on various parameters such as matter abundance, Hubble constant, and clustering amplitude, which are consistent with previous studies. By combining with other data sources, the constraints are further improved, leading to more stringent bounds on parameters like neutrino mass.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2023)
Article
Astronomy & Astrophysics
Pierre Zhang, Yifu Cai
Summary: The study re-analyzed the full shape of the BOSS galaxy two-point function within Lambda-CDM, with results constraining various cosmological parameters. The effect of redshift selection on the results was discussed, emphasizing the importance of systematic assessments for ongoing and future large-volume surveys.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2022)
Article
Astronomy & Astrophysics
Byeonghee Yu, Uros Seljak, Yin Li, Sukhdeep Singh
Summary: We present growth of structure constraints from the cosmological analysis of the power spectrum multipoles of SDSS-III BOSS DR12 galaxies. We use a galaxy power spectrum model that decomposes galaxies into halo mass bins and combines perturbation theory and halo model to model halo clustering. By constraining a single parameter f sigma 8 to Planck+BAO prior, we reduce the effects of prior volume and mismodeling. Our analysis yields tight constraints on f sigma 8 and discusses the sensitivity of cosmological parameter estimation to various factors.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2023)
Article
Astronomy & Astrophysics
Benedict Bahr-Kalus, Daniele Bertacca, Licia Verde, Alan Heavens
Summary: In this study, the impact of the observer's motion on the clustering signal in galaxy distribution and the Kaiser rocket effect is examined both analytically and numerically. While the Kaiser rocket effect can significantly bias cosmological parameter inference in idealistic full-sky surveys dominated by cosmic variance, it is not a major concern for forthcoming surveys with realistic masks and selection functions, except for possible implications on primordial non-Gaussianity studies. This systematic effect is well understood and should be accounted for using various approaches.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
Alexandre Barreira
Summary: The scale-dependent bias effect is a promising way to study the primordial non-Gaussianity parameter f(NL), but our limited knowledge of the linear PNG galaxy bias parameter b(phi) currently prevents us from accurately constraining f(NL).
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2022)
Article
Astronomy & Astrophysics
James M. Sullivan, Uros Seljak, Sukhdeep Singh
Summary: The updated Halo Zeldovich Perturbation Theory (HZPT) model provides an analytic and accurate description of the two-point statistics of dark matter on nonlinear scales, with applications to halo and galaxy clustering as well as galaxy-matter cross-correlation.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
Dan Pryer, Robert E. Smith, Robin Booth, Chris Blake, Alexander Eggemeier, Jon Loveday
Summary: The study derives expressions for the galaxy power spectrum convolved by survey window in real space, considering the geometric lightcone effect for full sky and deep redshift surveys. It investigates the impact of using the standard mean redshift approximation, showing both overall amplitude suppression and scale-dependent error compared to the 'true' spectrum. However, it also demonstrates that accurate approximation to the full model can be achieved by carefully choosing an 'effective fixed-time' within a certain range of scales.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2022)
Article
Astronomy & Astrophysics
Marcel Schmittfull, Marko Simonovic, Mikhail M. Ivanov, Oliver H. E. Philcox, Matias Zaldarriaga
Summary: An analytical forward model based on perturbation theory was developed to predict the redshift-space galaxy overdensity, finding residual noise characteristics in simulated galaxy density. Furthermore, comparison of galaxy velocities revealed that about 10% of galaxies contribute to half of the rms velocity residual in the simulated galaxy sample.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
Natali S. M. de Santi, L. Raul Abramo
Summary: This study proposes a machine learning approach to improve the covariance matrices used in the study of large-scale structure. By training convolutional neural networks to denoise the covariance matrices, the researchers were able to provide accurate and almost indistinguishable covariance matrices with only a small amount of data.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2022)
Article
Astronomy & Astrophysics
Marcel Schmittfull, Azadeh Moradinezhad Dizgah
Summary: Modern galaxy surveys focus on the galaxy power spectrum or 2-point correlation function to test and constrain cosmological models. By computing the cross-power spectrum between the squared galaxy density and the galaxy density, all contributions to the tree-level redshift-space galaxy bispectrum can be captured. This simple solution shows that the measurement pipeline matches analytical predictions and theoretical expectations on galaxy bias parameters and the logarithmic growth rate.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
Shi-Fan Chen, Zvonimir Vlah, Emanuele Castorina, Martin White
Summary: In this study, a method for computing the one-loop 2-point function of biased tracers in redshift space is presented using Lagrangian perturbation theory, with a full resummation of long-wavelength displacements and velocities. The model accurately predicts the power spectrum and correlation function of halos and mock galaxies, including baryon acoustic oscillation signal damping due to bulk galaxy motions. The study also compares this full resummation approach with other techniques and discusses the computation of resulting expressions numerically for efficient computation.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
Azadeh Moradinezhad Dizgah, Matteo Biagetti, Emiliano Sefusatti, Vincent Desjacques, Jorge Norena
Summary: Upcoming galaxy redshift surveys are expected to improve limits on primordial non-Gaussianity (PNG) through measurements in Fourier space. A Monte-Carlo Markov Chain analysis was performed to confront perturbation theory predictions with N-body simulations, focusing on the local model of PNG parameterized by f(NL). Informative priors on the linear non-Gaussian bias parameter can significantly improve constraints on f(NL) in statistical inference.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
Azadeh Moradinezhad Dizgah, Garrett K. Keating, Kirit S. Karkare, Abigail Crites, Shouvik Roy Choudhury
Summary: Line intensity mapping (LIM) is an important technique for mapping the large-scale structure of the universe and exploring cosmology. By measuring the auto-power spectra of CO rotational lines and the [C II] fine-structure line, LIM surveys can constrain properties of neutrinos and light relics. When combined with existing cosmic microwave background data, LIM surveys can significantly improve constraints on N-eff and M-nu.
ASTROPHYSICAL JOURNAL
(2022)
Article
Astronomy & Astrophysics
Chirag Modi, Martin White, Emanuele Castorina, Anze Slosar
Summary: By adding external galaxy distribution data to the 21-cm surveys, the lost long wavelength modes can be partially recovered. The spectroscopic sample performs better in reconstructing the largest modes, despite having lower number density.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
Azadeh Moradinezhad Dizgah, Farnik Nikakhtar, Garrett K. Keating, Emanuele Castorina
Summary: Line intensity mapping is an emerging technique that has the potential to accurately probe signals at different scales and redshifts. By using simulations and modeling, researchers have been able to accurately predict clustering power and stochastic contributions of intensity fluctuations. Furthermore, this technique shows promise in measuring the baryon acoustic oscillations, which has important implications for cosmological studies in the future.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2022)
Article
Astronomy & Astrophysics
Emanuele Castorina, Enea Di Dio
Summary: Measurements of galaxy clustering in Fourier space provide insights into the early Universe and the effects of Primordial Non Gaussianities. Relativistic effects can complicate the interpretation of data and may diverge in the Infra-Red. This work calculates the ensemble average of a commonly used Fourier space estimator, considering all general relativistic effects. The study finds that once the individual divergent GR terms are taken into account, there is no Infra-Red sensitivity in the observable. Additionally, the importance of GR effects, including lensing magnification, in interpreting the galaxy power spectrum multipoles is investigated, revealing them to be generally small corrections to the leading redshift space distortions term.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2022)
Editorial Material
Astronomy & Astrophysics
Luca Teodori, Kfir Blum, Emanuele Castorina, Marko Simonovic, Yotam Soreq
Summary: In this paper, we discuss the issue of modeling degeneracies in strong lensing measurements of the Hubble parameter H-0. We highlight the importance of considering weak lensing effects associated with different segments of the line of sight, and propose the inclusion of external convergence terms to avoid bias in the inferred value of H-0. We also show that the use of imaging data for multiple strongly-lensed sources cannot fully resolve the mass sheet degeneracy.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2022)
Article
Astronomy & Astrophysics
Suvodip Mukherjee, Azadeh Moradinezhad Dizgah
Summary: This study proposes a novel data-driven, multi-messenger technique to investigate the connection between compact objects (such as neutron stars, black holes, and supermassive black holes) and the chemical composition of galaxies. By analyzing the correlation between gravitational waves and atomic/molecular emission-line signals, it is possible to measure the delay time distribution and provide data-driven constraints.
ASTROPHYSICAL JOURNAL LETTERS
(2022)
Article
Astronomy & Astrophysics
Maria Archidiacono, Emanuele Castorina, Diego Redigolo, Ennio Salvioni
Summary: This study initiates the exploration of the cosmology of dark fifth forces, which are new forces acting solely on Dark Matter. It is found that the dark fifth force can be realized by a light scalar coupled to Dark Matter, and it has significant effects on the background cosmology and linear perturbations.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2022)
Article
Astronomy & Astrophysics
Kevin Pardede, Federico Rizzo, Matteo Biagetti, Emanuele Castorina, Emiliano Sefusatti, Pierluigi Monaco
Summary: A method to perform exact convolution of the model prediction for bispectrum multipoles in redshift space with the survey window function is presented. By extending a widely applied method for power spectrum convolution to bispectrum and utilizing a 2D-FFTlog algorithm, accurate results are obtained.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2022)
Article
Astronomy & Astrophysics
Fabien Lacasa, Marie Aubert, Philippe Baratta, Julien Carron, Adelie Gorce, Sylvain Gouyou Beauchamps, Louis Legrand, Azadeh Moradinezhad Dizgah, Isaac Tutusaus
Summary: This paper presents a formula for calculating the precision matrix of super-sample covariance (SSC) and demonstrates its applications in cosmological analyses. The study shows that inaccurate modeling of SSC responses has a significant impact on cosmological constraints in stage IV surveys.
ASTRONOMY & ASTROPHYSICS
(2023)
Article
Astronomy & Astrophysics
ChangHoon Hahn, Michael Eickenberg, Shirley Ho, Jiamin Hou, Pablo Lemos, Elena Massara, Chirag Modi, Azadeh Moradinezhad Dizgah, Bruno Regaldo-Saint Blancard, Muntazir M. Abidi
Summary: Simulation-Based Inference of Galaxies (SIMBIG) is a forward modeling framework that uses simulation-based inference to analyze galaxy clustering. It accurately infers the parameters of galaxy clustering and effectively handles observational systematics. The framework has been validated through a mock challenge, demonstrating its robustness and capability to handle different statistical measures.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2023)
Article
Astronomy & Astrophysics
Jiamin Hou, Azadeh Moradinezhad Dizgah, ChangHoon Hahn, Elena Massara
Summary: Extracting non-Gaussian information from higher-order clustering statistics is crucial for upcoming galaxy surveys. We investigate the information content of redshift-space weighted skew spectra and show that they significantly improve parameter constraints compared to power spectrum multipoles. Additionally, we find that skew spectra provide competitive constraints compared to bispectrum monopole and outperform it for all cosmological parameters.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2023)
Article
Astronomy & Astrophysics
Elena Massara, Francisco Villaescusa-Navarro, ChangHoon Hahn, Muntazir M. Abidi, Michael Eickenberg, Shirley Ho, Pablo Lemos, Azadeh Moradinezhad Dizgah, Bruno Regaldo-Saint Blancard
Summary: Marked power spectra are two-point statistics of a marked field obtained by weighting each location with a function that depends on the local density around that point. We consider marked power spectra of the galaxy field in redshift space that up-weight low-density regions, and we perform a Fisher matrix analysis to assess the information content of this type of statistics using the Molino mock catalogs built on the Quijote simulations. Our results show that each of the four marked power spectra can tighten the standard power spectrum constraints on the cosmological parameters by 15%-25% and on σ(8) by a factor of 2. When combining the standard and four marked power spectra, the improvement in the power spectrum constraints is equal to a factor of 6 for σ(8) and a factor of 2.5-3 for the other parameters.
ASTROPHYSICAL JOURNAL
(2023)