Article
Astronomy & Astrophysics
Dominik Zurcher, Janis Fluri, Raphael Sgier, Tomasz Kacprzak, Alexandre Refregier
Summary: The study compared the constraining power of three map-based non-Gaussian statistics with the angular power spectrum in the Omega(m)-sigma(8) plane, finding that non-Gaussian statistics provide tighter constraints. A combination of non-Gaussian statistics and the angular power spectrum increased the constraining power and reduced the error on S8.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
Alex Krolewski, Simone Ferraro, Martin White
Summary: Recent lensing measurements at low redshifts suggest that the amplitude of lensing in the universe may be lower than predicted by the Lambda CDM model based on Planck CMB data. By analyzing the auto-and cross-correlation signal of unWISE galaxies and Planck CMB lensing maps, cosmological parameters at low redshifts have been inferred, showing tensions with the CMB predictions. The combination of blue, green, and red unWISE samples gives a value of S-8 = 0.784 +/- 0.015, consistent with other low-redshift lensing measurements and in tension with the CMB predictions from Planck.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
Silvan Fischbacher, Tomasz Kacprzak, Jonathan Blazek, Alexandre Refregiera
Summary: Intrinsic alignment (IA) modelling and photometric redshift estimation are sources of systematic uncertainty in weak lensing surveys. Redshift errors can lead to biases in cosmological constraints, but marginalizing over redshift parameters can partially resolve these biases. The uncertainty requirements for redshift parameters depend on the IA model and the stage of the survey. The interplay between redshift systematics and IA modelling is unlikely to explain the current S8-tension between cosmic shear results and CMB measurements.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2023)
Article
Astronomy & Astrophysics
Boryana Hadzhiyska, Carlos Garcia-Garcia, David Alonso, Andrina Nicola, Anze Slosar
Summary: This study reanalyzes cosmic shear and galaxy clustering data from the first year of the Dark Energy Survey, using a Hybrid Effective Field Theory (HEFT) approach to model the galaxy-matter relation on weakly non-linear scales. The results show an improvement in cosmological constraints by extending the galaxy clustering scale range and using the HEFT model to explain the data up to certain wavenumbers. Constraints on parameters such as (S-8, Omega(m)) and Hubble parameter are derived, but the results are investigative and subject to caveats discussed in the text.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
Dipak Munshi, Hayden Lee, Cora Dvorkin, Jason D. McEwen
Summary: This paper introduces two kurt-spectra to study the fourth-order statistics of weak lensing convergence maps. The shapes of these spectra are investigated in relation to source redshifts and smoothing angular scales using numerical simulations. Estimators for beyond fourth-order spectra are provided, and their results are compared with theoretical predictions.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2022)
Article
Astronomy & Astrophysics
Carlos Garcia-Garcia, David Alonso, Pedro G. Ferreira, Boryana Hadzhiyska, Andrina Nicola, Carles Sanchez, Anze Slosar
Summary: This paper introduces a method to quantify and propagate the uncertainties on the source redshift distribution in two different surveys sharing the same calibrating sample. The results show that the uncertainties on the redshift distributions do not significantly affect the final constraints on cosmological parameters.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2023)
Article
Astronomy & Astrophysics
Tomasz Kacprzak, Janis Fluri, Aurel Schneider, Alexandre Refregier, Joachim Stadel
Summary: We have introduced CosMoGRIDV1, a large set of lightcone simulations for map-level cosmological inference with probes of large scale structure. It is designed for cosmological parameter measurement based on Stage-III photometric surveys with non-Gaussian statistics and machine learning. CosMoGRIDV1 covers the wCDM model and includes various parameters, simulations, and correction models for baryon feedback effects.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2023)
Article
Astronomy & Astrophysics
Sambit K. Giri, Aurel Schneider
Summary: This paper introduces an emulator for baryonic suppression of the matter power spectrum based on a baryonification model with seven free parameters. The emulator can recover the power spectra of hydro-dynamical simulations with sub-percent precision and establish a connection between baryonic suppression, gas, and stellar fractions in haloes. Predictions of deviation from a dark-matter-only power spectrum using measured X-ray gas fractions lead to a constraint on suppression levels at various wave numbers, with a maximum of 20-28% at around k ≈ 7 h/Mpc (68% confidence level).
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
Sven Heydenreich, Benjamin Brueck, Joachim Harnois-Deraps
Summary: This study demonstrates the power of persistent homology as a new method to extract cosmological information more efficiently from weak gravitational lensing data, achieving superior constraints in mock data and Euclid-like simulations.
ASTRONOMY & ASTROPHYSICS
(2021)
Article
Astronomy & Astrophysics
D. Zurcher, J. Fluri, V Ajani, S. Fischbacher, A. Refregier, T. Kacprzak
Summary: The next generation of weak lensing surveys will enable us to measure the matter distribution of the local universe with unprecedented precision, which opens up the possibility to resolve non-Gaussian features of the convergence field. We extend the methodology introduced in a previous forecast paper to match these new requirements and provide forecasts for the constraints on the $w$CDM parameters from stage 3 and 4 weak lensing surveys. Our results show that the combination of different summary statistics, including the angular power spectrum, peak counts, and Minkowski functionals following Starlet filtering, significantly improves the constraints on cosmology.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
Anna Balaudo, Alice Garoffolo, Matteo Martinelli, Suvodip Mukherjee, Alessandra Silvestri
Summary: We investigate the synergy between future galaxy surveys and gravitational wave (GW) experiments in constraining late-time cosmology. We find that GW weak lensing (GW-WL) can improve the accuracy on non-ACDM parameters in some scenarios, doubling the accuracy of the galaxy signal. This offers the potential for GW-WL to become a cosmological probe complementary to large-scale structure surveys, particularly for parameters that cannot be constrained by other GW probes.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2023)
Article
Astronomy & Astrophysics
Ryu Makiya, Issha Kayo, Eiichiro Komatsu
Summary: An algorithm is proposed to self-consistently generate mock weak gravitational lensing convergence fields and galaxy distributions in redshift space. The simulation results show that the galaxy-shear cross-correlation measurements from the Subaru Hyper Suprime-Cam (HSC) and Prime Focus Spectrograph (PFS) surveys are of high quality, with significant signal-to-noise ratios detected at different redshift bins.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
Giuseppe Fanizza, Enea Di Dio, Ruth Durrer, Giovanni Marozzi
Summary: This paper computes the weak lensing Jacobi map at first order in perturbation theory and demonstrates its gauge invariance and symmetry. It is shown that linear perturbations do not induce any rotation, but vector and tensor perturbations do induce B-modes in the shear. Contrary to previous claims, the shear B-mode power spectrum is not fully determined by the rotation power spectrum, and the E-mode shear power spectrum is not determined by the convergence power spectrum. While this difference is small for scalar perturbations, it becomes significant for tensor perturbations, i.e. gravitational waves.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2022)
Article
Astronomy & Astrophysics
Martin White, Rongpu Zhou, Joseph DeRose, Simone Ferraro, Shi-Fan Chen, Nickolas Kokron, Stephen Bailey, David Brooks, Juan Garcia-Bellido, Julien Guy, Klaus Honscheid, Robert Kehoe, Anthony Kremin, Michael Levi, Nathalie Palanque-Delabrouille, Claire Poppett, David Schlegel, Gregory Tarle
Summary: Using luminous red galaxies selected from imaging surveys for targeting by the Dark Energy Spectroscopic Instrument (DESI) in combination with CMB lensing maps from the Planck collaboration, researchers probed the amplitude of large-scale structure over 0.4 <= z <= 1. Their findings suggest a slower growth of structure at low redshift than model predictions, with only modest significance.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2022)
Article
Astronomy & Astrophysics
Pauline Vielzeuf, Matteo Calabrese, Carmelita Carbone, Giulio Fabbian, Carlo Baccigalupi
Summary: Cosmic voids are powerful probes of cosmology, especially in studying the nature of gravity and the neutrino mass. Recent studies have shown that measurements of void imprint on the lensed Cosmic Microwave Background (CMB) are in tension with expectations based on simulations, suggesting the possibility of non-standard cosmological signatures due to massive neutrinos. This study uses cosmological simulations with massive neutrino cosmologies to investigate the impact of neutrinos on void properties observed in photometric surveys and the void-CMB lensing cross-correlation. The results provide insights into the potential role of massive neutrinos in explaining the tension observed and propose a new quantity for distinguishing different neutrino masses through future observations.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2023)
Article
Astronomy & Astrophysics
Johan L. Freiherr von Forstner, Mateja Dumbovi, Christian Moestl, Jingnan Guo, Athanasios Papaioannou, Robert Elftmann, Zigong Xu, Jan Christoph Terasa, Alexander Kollhoff, Robert F. Wimmer-Schweingruber, Javier Rodriguez-Pacheco, Andreas J. Weiss, Juergen Hinterreiter, Tanja Amerstorfer, Maike Bauer, Anatoly Belov, Maria A. Abunina, Timothy Horbury, Emma E. Davies, Helen O'Brien, Robert C. Allen, G. Bruce Andrews, Lars Berger, Sebastian Boden, Ignacio Cernuda Cangas, Sandra Eldrum, Francisco Espinosa Lara, Raul Gomez Herrero, John R. Hayes, George C. Ho, Shrinivasrao R. Kulkarni, W. Jeffrey Lees, Cesar Martin, Glenn M. Mason, Daniel Pacheco, Manuel Prieto Mateo, Ali Ravanbakhsh, Oscar Rodriguez Polo, Sebastian Sanchez Prieto, Charles E. Schlemm, Helmut Seifert, Kush Tyagi, Mahesh Yedla
Summary: This study presents observations of the first coronal mass ejection (CME) observed by the Solar Orbiter spacecraft and the associated Forbush decrease (FD) measured by the High Energy Telescope (HET). The study emphasizes the importance of multi-spacecraft observations and data-based modeling for understanding space weather impacts in the inner heliosphere.
ASTRONOMY & ASTROPHYSICS
(2021)
Article
Astronomy & Astrophysics
E. E. Davies, C. Mostl, M. J. Owens, A. J. Weiss, T. Amerstorfer, J. Hinterreiter, M. Bauer, R. L. Bailey, M. A. Reiss, R. J. Forsyth, T. S. Horbury, H. O'Brien, V Evans, V Angelini, D. Heyner, I Richter, H-U Auster, W. Magnes, W. Baumjohann, D. Fischer, D. Barnes, J. A. Davies, R. A. Harrison
Summary: This study utilized data from multiple satellites to determine the global shape and evolution of a coronal mass ejection (CME) in the inner heliosphere. Results indicate a clear flattening of the CME cross-section, and a disagreement with previous studies was found in the relationship between magnetic field strength and heliocentric distance.
ASTRONOMY & ASTROPHYSICS
(2021)
Article
Astronomy & Astrophysics
Christian Moestl, Andreas J. Weiss, Martin A. Reiss, Tanja Amerstorfer, Rachel L. Bailey, Juergen Hinterreiter, Maike Bauer, David Barnes, Jackie A. Davies, Richard A. Harrison, Johan L. Freiherr von Forstner, Emma E. Davies, Daniel Heyner, Tim Horbury, Stuart D. Bale
Summary: This study presents the first search for multipoint in situ and imaging observations of interplanetary coronal mass ejections (ICMEs). The data analysis includes magnetic-field and plasma observations made by multiple spacecraft and the connection with coronagraph and heliospheric imaging observations. The results identify ICME events and provide valuable information for modeling their magnetic structure, interplanetary evolution, and propagation of solar energetic particles.
ASTROPHYSICAL JOURNAL LETTERS
(2022)
Article
Astronomy & Astrophysics
Sambit K. Giri, Aurel Schneider
Summary: This paper introduces an emulator for baryonic suppression of the matter power spectrum based on a baryonification model with seven free parameters. The emulator can recover the power spectra of hydro-dynamical simulations with sub-percent precision and establish a connection between baryonic suppression, gas, and stellar fractions in haloes. Predictions of deviation from a dark-matter-only power spectrum using measured X-ray gas fractions lead to a constraint on suppression levels at various wave numbers, with a maximum of 20-28% at around k ≈ 7 h/Mpc (68% confidence level).
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
R. L. Bailey, R. Leonhardt, C. Moestl, C. Beggan, M. A. Reiss, A. Bhaskar, A. J. Weiss
Summary: The forecasting of local GIC effects has been mostly based on the proxy forecasting of dB/dt, and little attention has been given to directly forecasting geoelectric fields or GICs themselves. In this study, machine learning tools, specifically recurrent neural networks or LSTMs, are employed to predict geoelectric fields and GICs using solar wind observations as input. The results show that the LSTM model performs better in predicting GICs when trained on specific substation values, but only a fraction of the largest GICs are correctly predicted. The model has a correlation of around 0.6 with measurements and a root-mean-square error of 0.7 A. The probability of detecting mild activity in GICs is approximately 50%, while it is 15% for larger GICs.
SPACE WEATHER-THE INTERNATIONAL JOURNAL OF RESEARCH AND APPLICATIONS
(2022)
Article
Astronomy & Astrophysics
Mischa Knabenhans, Thejs Brinckmann, Joachim Stadel, Aurel Schneider, Romain Teyssier
Summary: We compare the performance of HALOFIT, HMCODE, and EUCLIDEMULATOR1 in predicting power spectrum and cosmological parameters. EUCLIDEMULATOR1 shows an average improvement of up to 17% in sensitivity compared to the other two codes, with the highest improvements for the Hubble parameter (42%) and the dark energy equation of state (26%). The choice of power spectrum predictor also affects the risk of computing biased mean cosmology in parameter estimations.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
Aurel Schneider, Sambit K. Giri, Stefania Amodeo, Alexandre Refregier
Summary: This paper investigates the role of baryonic feedback effects in cosmology using weak-lensing data and observations of gas around galaxy clusters. The results suggest that baryonic feedback effects are stronger than predicted by most simulations and show significant suppression at certain wave-modes. Furthermore, including baryonic effects in the analysis reduces the tension with Planck satellite data, indicating their contribution to reconciling observational and theoretical results.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
Sambit K. Giri, Aurel Schneider, Francisco Maion, Raul E. Angulo
Summary: It has been found that sample variance is the primary source of uncertainty in analyzing the 21 cm signal at large scales during reionization. By using the 'fixing and pairing' approach, sample variance can be significantly reduced, improving the simulation precision of large-scale clustering signals and reducing computing costs.
ASTRONOMY & ASTROPHYSICS
(2022)
Article
Astronomy & Astrophysics
A. J. Weiss, T. Nieves-Chinchilla, C. Moestl, M. A. Reiss, T. Amerstorfer, R. L. Bailey
Summary: This study aims to develop a new analytical flux rope model that can describe flux rope structure with varying curvature and torsion. In the first iteration of the model, a circular cross-section of constant size is considered. The study finds that the twist of the magnetic field changes when the geometry deviates from a cylinder or torus, and new types of magnetic field profiles can be generated.
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
(2022)
Article
Astronomy & Astrophysics
Jozef Bucko, Sambit K. Giri, Aurel Schneider
Summary: From observations at low and high redshifts, it is well known that the bulk of dark matter (DM) has to be stable or very long-lived, but the possibility of a small fraction or all of the DM decaying with a significantly longer half-life time than the age of the Universe is not ruled out. In this study, the researchers investigated models in which a fraction or all DM decays into radiation, focusing on the long-lived regime. They used data from the Kilo-Degree Survey (KiDS) for weak-lensing analysis and CMB data from Planck. The results showed that the constraints on DM decay are more stringent from CMB data than from weak-lensing data.
ASTRONOMY & ASTROPHYSICS
(2023)
Article
Astronomy & Astrophysics
Tomasz Kacprzak, Janis Fluri, Aurel Schneider, Alexandre Refregier, Joachim Stadel
Summary: We have introduced CosMoGRIDV1, a large set of lightcone simulations for map-level cosmological inference with probes of large scale structure. It is designed for cosmological parameter measurement based on Stage-III photometric surveys with non-Gaussian statistics and machine learning. CosMoGRIDV1 covers the wCDM model and includes various parameters, simulations, and correction models for baryon feedback effects.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2023)
Article
Astronomy & Astrophysics
Andrej Obuljen, Marko Simonovic, Aurel Schneider, Robert Feldmann
Summary: In this study, an analytical forward model based on perturbation theory is used to predict the neutral hydrogen (HI) overdensity maps at low redshifts. The model is compared to the simulated HI from the IllustrisTNG magneto-hydrodynamical simulation TNG300-1 to assess its performance. The results show that HI is a biased tracer of the underlying matter field and the model accurately describes the simulated HI power spectrum. The model also provides a simple and efficient way to generate accurate HI mock data.
Article
Astronomy & Astrophysics
Aurel Schneider, Timothee Schaeffer, Sambit K. Giri
Summary: This paper introduces a new analytical tool called the halo model of reionization (HMreio) and validates it against seminumerical code 21 CMFAST. The tool is then used for Monte-Carlo Markov-Chain (MCMC) forecast analysis and shows competitive constraints on cosmological parameters. It can help solve current cosmological tensions related to the Hubble parameter and the matter clustering amplitude, and provide strong constraints on the neutrino mass hierarchy.
Article
Astronomy & Astrophysics
Janis Fluri, Tomasz Kacprzak, Aurelien Lucchi, Aurel Schneider, Alexandre Refregier, Thomas Hofmann
Summary: In this study, we conducted a wCDM analysis of KiDS-1000 weak lensing maps using graphconvolutional neural networks (GCNN), and obtained constraints on cosmological parameters. By generating a large number of tomographic mock surveys and performing spherical and power spectrum analyses, we found that baryonic corrections have an impact on the constraints of the degeneracy parameter.
Article
Astronomy & Astrophysics
Sambit K. Giri, Aurel Schneider
Summary: This paper investigates the potential of the 21-cm signal from the epoch of cosmic dawn to constrain mixed dark matter scenarios. It shows how the scenarios affect the global signal and power spectrum and provides constraints on the mass and fraction of noncold dark matter.