Article
Astronomy & Astrophysics
William L. Matthewson, Ruth Durrer
Summary: The study derived and tested an approximation for the angular power spectrum of galaxy number counts in the flat sky limit, providing accurate results for low multipoles. The accuracy of density and RSD terms at equal redshifts is around 0.2% for z < 3 and 0.5% at z = 5, while precision is better than 5% for very small redshift differences at unequal redshifts. The flat sky approximation is computationally simpler and can be valuable for data analysis and forecasts for upcoming galaxy surveys.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
Viraj Nistane, Mona Jalilvand, Julien Carron, Ruth Durrer, Martin Kunz
Summary: In this study, we propose an estimator for the lensing potential using galaxy number counts, which includes a linear and a quadratic term. Our results demonstrate that this estimator has a significantly higher signal-to-noise ratio compared to the corresponding estimator from intensity mapping. The improved signal-to-noise ratio is attributed to the additional lensing term in the number count angular power spectrum, which appears at linear order. We estimate the signal-to-noise ratio for future photometric surveys and find that it can reach an order of magnitude of 30, particularly at high redshifts (z greater than or similar to 1.5). Therefore, we argue that number counts in photometric surveys are an excellent tool for measuring tomographic lensing spectra.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2022)
Article
Astronomy & Astrophysics
Catherine Heymans, Tilman Troester, Marika Asgari, Chris Blake, Hendrik Hildebrandt, Benjamin Joachimi, Konrad Kuijken, Chieh-An Lin, Ariel G. Sanchez, Jan Luca van den Busch, Angus H. Wright, Alexandra Amon, Maciej Bilicki, Jelte de Jong, Martin Crocce, Andrej Dvornik, Thomas Erben, Maria Cristina Fortuna, Fedor Getman, Benjamin Giblin, Karl Glazebrook, Henk Hoekstra, Shahab Joudaki, Arun Kannawadi, Fabian Koehlinger, Chris Lidman, Lance Miller, Nicola R. Napolitano, David Parkinson, Peter Schneider, HuanYuan Shan, Edwin A. Valentijn, Gijs Verdoes Kleijn, Christian Wolf
Summary: This study combines weak gravitational lensing observations from KiDS-1000, redshift-space galaxy clustering observations from BOSS, and galaxy-galaxy lensing observations from overlapping surveys to constrain the structure growth parameter S-8, resulting in a discrepancy with the Planck observations by 8.3% relative to Planck. The systematic uncertainties identified through various analyses are incorporated into the cosmological analysis, revealing a tension in the matter fluctuation amplitude parameter, sigma(8).
ASTRONOMY & ASTROPHYSICS
(2021)
Article
Astronomy & Astrophysics
Zvonimir Vlah, Nora Elisa Chisari, Fabian Schmidt
Summary: Intrinsic galaxy alignments play a significant role in the statistics of galaxy shapes. A formalism using spherical tensors to project galaxy shapes onto the flat sky and calculate two-point functions at next-to-leading order, as well as leading-order three-point functions, has been presented. The results are provided in a numerical implementation-friendly format.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
Daniel A. Torres-Ballesteros, Leonardo Castaneda
Summary: In this work, we introduce a software package called RELENSING, which models galaxy clusters through gravitational lensing. The package provides a free-form approach to compute the gravitational deflection potential and constrain strong lensing. Our results show that by smoothing the deflection potential, the method can better recover the mass profile of galaxy clusters.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
Daniel A. Torres-Ballesteros, Leonardo Castaneda
Summary: In this work, the software package RELENSING is introduced, which aims to model galaxy clusters through gravitational lensing. This package expands the available software options and provides a variety of models for the scientific community to compare and validate physical results. The approach implemented in RELENSING calculates the gravitational deflection potential on an adaptive irregular grid, allowing for characterization of the cluster as a gravitational lens. By applying a smoothing technique, the capability of the approach to recover the mass profile, magnification map, and critical and caustic curves of galaxy clusters is improved.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
Xiangchong Li, Rachel Mandelbaum
Summary: Shear estimation bias, caused by galaxy detection and blending identification, is a known issue in current and future weak-lensing surveys. This study presents an analytical correction method that is accurate and easier to use compared to numerical shearing. By deriving the linear shear responses of pixel values and galaxy properties, we correct for biases in galaxy detection and sample selection. With the analytical covariance matrix, we also correct for noise biases in galaxy shape measurement and the detection/selection process.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
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
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
Jeremie Francfort, Ruth Durrer, Giulia Cusin
Summary: This paper introduces a new observable to measure cosmic shear, which is sensitive to the angle between the orientation of a galaxy and the polarization direction of its radio emission. Despite the expected low signal-to-noise ratio for a single measurement, the fact that all galaxies in a given pixel experience the same shear allows to overcome the noise. Another advantage of this method is that the signal is not affected by intrinsic alignment.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2022)
Article
Astronomy & Astrophysics
Chenxiao Zeng, Andres N. Salcedo, Hao-Yi Wu, Christopher M. Hirata
Summary: In this study, we investigate the use of three correlation functions - cluster lensing, the cluster-galaxy cross-correlation function, and the galaxy autocorrelation function - to self-calibrate optical cluster selection bias in a richness-selected sample. We develop mock catalogues of redMaGiC-like galaxies and redMaPPer-like clusters using N-body simulations and counts-in-cylinders around massive haloes as a richness proxy. We find that projection effects significantly boost both the projected and three-dimensional correlation functions. Likelihood analysis shows that the selection bias can be constrained at the 10 per cent level.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
Dylan Cromer, Nicholas Battaglia, Hironao Miyatake, Melanie Simet
Summary: This paper introduces a new flexible model to capture the baryonic and dark matter density distributions in galaxy clusters, and tests it on simulated data, finding that including the baryonic term reduces the bias in average mass estimation compared to a dark matter-only model. To mitigate computational complexity, an emulator is constructed for faster parameter inference, and an open-source software framework called maszcal is provided. The importance of improving mass-calibration techniques is emphasized.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2022)
Article
Astronomy & Astrophysics
Lorenzo Pizzuti, Ippocratis D. Saltas, Keiichi Umetsu, Barbara Sartoris
Summary: This study uses observations of galaxy clusters MACS J1206.2-0847 and Abell S1063, combined with strong/weak lensing and kinematics measurements, to constrain the relativistic sector of the DHOST dark energy theories. New constraints are obtained and potential sources of systematic errors are investigated.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
A. Kovacs, N. Jeffrey, M. Gatti, C. Chang, L. Whiteway, N. Hamaus, O. Lahav, G. Pollina, D. Bacon, T. Kacprzak, B. Mawdsley, S. Nadathur, D. Zeurcher, J. Garcia-Bellido, A. Alarcon, A. Amon, K. Bechtol, G. M. Bernstein, A. Campos, A. Carnero Rosell, M. Carrasco Kind, R. Cawthon, R. Chen, A. Choi, J. Cordero, C. Davis, J. DeRose, C. Doux, A. Drlica-Wagner, K. Eckert, F. Elsner, J. Elvin-Poole, S. Everett, A. Ferte, G. Giannini, D. Gruen, R. A. Gruendl, I Harrison, W. G. Hartley, K. Herner, E. M. Huff, D. Huterer, N. Kuropatkin, M. Jarvis, P. F. Leget, N. MacCrann, J. McCullough, J. Muir, J. Myles, A. Navarro-Alsina, S. Pandey, J. Prat, M. Raveri, R. P. Rollins, A. J. Ross, E. S. Rykoff, C. Sanchez, L. F. Secco, I Sevilla-Noarbe, E. Sheldon, T. Shin, M. A. Troxel, I Tutusaus, T. N. Varga, B. Yanny, B. Yin, Y. Zhang, J. Zuntz, M. Aguena, S. Allam, F. Andrade-Oliveira, J. Annis, E. Bertin, D. Brooks, D. Burke, J. Carretero, M. Costanzi, L. N. da Costa, M. E. S. Pereira, T. Davis, J. De Vicente, S. Desai, H. T. Diehl, I Ferrero, B. Flaugher, P. Fosalba, J. Frieman, E. Gaztanaga, D. Gerdes, T. Giannantonio, J. Gschwend, G. Gutierrez, S. Hinton, D. L. Hollowood, K. Honscheid, D. James, K. Kuehn, M. Lima, M. A. G. Maia, J. L. Marshall, P. Melchior, F. Menanteau, R. Miquel, R. Morgan, R. Ogando, F. Paz-Chinchon, A. Pieres, A. A. Plazas, M. Rodriguez Monroy, K. Romer, A. Roodman, E. Sanchez, M. Schubnell, S. Serrano, M. Smith, M. Soares-Santos, E. Suchyta, M. E. C. Swanson, G. Tarle, D. Thomas, C-H To, J. Weller
Summary: The study confirms the detection of the Eridanus supervoid as a significant underdensity in the Cold Spot's direction, with a lower lensing signal amplitude than expected. The results emphasize the causal relation between these individually rare structures in the cosmic web and in the Cosmic Microwave Background, encouraging more detailed future surveys in the Cold Spot region.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
G. Zacharegkas, C. Chang, J. Prat, S. Pandey, I Ferrero, J. Blazek, B. Jain, M. Crocce, J. DeRose, A. Palmese, S. Seitz, E. Sheldon, W. G. Hartley, R. H. Wechsler, S. Dodelson, P. Fosalba, E. Krause, Y. Park, C. Sanchez, A. Alarcon, A. Amon, K. Bechtol, M. R. Becker, G. M. Bernstein, A. Campos, A. Carnero Rosell, M. Carrasco Kind, R. Cawthon, R. Chen, A. Choi, J. Cordero, C. Davis, H. T. Diehl, C. Doux, A. Drlica-Wagner, K. Eckert, J. Elvin-Poole, S. Everett, A. Ferte, M. Gatti, G. Giannini, D. Gruen, R. A. Gruendl, I Harrison, K. Herner, E. M. Huff, M. Jarvis, N. Kuropatkin, P-F Leget, N. MacCrann, J. McCullough, J. Myles, A. Navarro-Alsina, A. Porredon, M. Raveri, R. P. Rollins, A. Roodman, A. J. Ross, E. S. Rykoff, L. F. Secco, I Sevilla-Noarbe, T. Shin, M. A. Troxel, I Tutusaus, T. N. Varga, B. Yanny, B. Yin, Y. Zhang, J. Zuntz, T. M. C. Abbott, M. Aguena, S. Allam, F. Andrade-Oliveira, J. Annis, D. Bacon, E. Bertin, D. Brooks, D. L. Burke, J. Carretero, F. J. Castander, M. Costanzi, L. N. da Costa, M. E. S. Pereira, S. Desai, J. P. Dietrich, P. Doel, A. E. Evrard, B. Flaugher, J. Frieman, J. Garcia-Bellido, E. Gaztanaga, J. Gschwend, G. Gutierrez, S. R. Hinton, D. L. Hollowood, K. Honscheid, B. Hoyle, D. J. James, K. Kuehn, M. Lima, M. A. G. Maia, J. L. Marshall, P. Melchior, F. Menanteau, R. Miquel, J. Muir, R. L. C. Ogando, F. Paz-Chinchon, A. Pieres, E. Sanchez, S. Serrano, M. Smith, E. Suchyta, G. Tarle, D. Thomas, C. To, R. D. Wilkinson
Summary: Galaxy-galaxy lensing is an important tool for studying the connection between galaxies and dark matter haloes. This study extends the measurement and modelling of this lensing signal to highly non-linear scales, finding that galaxies typically reside in dark matter haloes of roughly constant mass. By constraining these halo properties, our understanding of galaxy evolution and cosmology can be improved.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
Arka Banerjee, Emanuele Castorina, Francisco Villaescusa-Navarro, Travis Court, Matteo Viel
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2020)
Article
Astronomy & Astrophysics
Emanuele Castorina, Martin White
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2020)
Article
Astronomy & Astrophysics
Emanuele Castorina, Azadeh Moradinezhad Dizgah
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2020)
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
Multidisciplinary Sciences
B. Buchmann, L. K. Engelbrecht, P. Fernandez, F. P. Hutterer, M. K. Raich, C. H. Scheel, A. R. Bausch
Summary: The authors estimated COVID-19 mortality in Italy using a counterfactual time series analysis, finding that the actual deaths were approximately 1.5 times higher than official statistics. The proportion of population deaths and infection rates were also calculated for the most affected regions, showing significant differences from reported numbers.
NATURE COMMUNICATIONS
(2021)
Article
Astronomy & Astrophysics
V. Bohm, Y. Feng, M. E. Lee, B. Dai
Summary: MADLens is a Python package designed to produce non-Gaussian lensing convergence maps with unprecedented precision at arbitrary source redshifts. It achieves high accuracy through a combination of highly parallelizable algorithms, a sub-evolution scheme in the lensing projection, and a machine-learning inspired sharpening step. MADLens is fully differentiable with respect to initial conditions and cosmological parameters, making it useful for Bayesian inference algorithms and large, high-resolution simulation sets for deep-learning-based lensing analysis tools.
ASTRONOMY AND COMPUTING
(2021)
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)
Article
Astronomy & Astrophysics
Noah Sailer, Emanuele Castorina, Simone Ferraro, Martin White
Summary: By using a Fisher matrix formalism based on recent advances in Lagrangian perturbation theory, constraints for future spectroscopic and 21-cm surveys on the standard cosmological model and its extensions were forecasted and compared with those achievable by current or near-future surveys, such as DESI and Euclid, under the same forecasting formalism. Additionally, comparisons were made between the formalism used and traditional linear methods.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
C. Modi, F. Lanusse, U. Seljak
Summary: FlowPM is a Particle-Mesh (PM) cosmological N-body code implemented in Mesh-TensorFlow for GPU-accelerated, distributed, and differentiable simulations. A novel multi-grid scheme based on multiresolution pyramids is implemented to compute large-scale forces efficiently on distributed platforms, achieving significant speed-up compared to Python-based PM code. This tool can be used for efficiently solving large scale cosmological inference problems, including the reconstruction of cosmological fields in a forward model Bayesian framework with hybrid PM and neural network forward model.
ASTRONOMY AND COMPUTING
(2021)
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
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
Vanessa Bohm, Jia Liu
Summary: Individual productivity among astronomers was boosted during the COVID-19 pandemic, but the improvement was not equally shared by men and women. A smaller fraction of papers were written by female astronomers and fewer women were among incoming new researchers in many countries. Even though female astronomers became more productive during COVID, the level of improvement is smaller than for men.