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
Calum Murray, James G. Bartlett, Emmanuel Artis, Jean-Baptiste Melin
Summary: In this study, weak lensing mass estimates were presented for 458 galaxy clusters using weak lensing data. The mass-richness relation and the correlation between cluster richness and weak lensing masses were explored. The results showed some discrepancies compared to other studies.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
Sihao Cheng, Brice Menard
Summary: Researchers have shown that the scattering transform is an effective tool for cosmological parameter estimation, especially for dark energy and neutrino mass parameters, due to its sensitivity. The scattering transform exhibits higher sensitivity in noiseless scenarios and a more Gaussian sampling distribution at noise levels, making it suitable for accurate cosmological inference. It is considered a preferred statistic considering both constraining power and likelihood properties.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(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
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
Stijn N. B. Debackere, Henk Hoekstra, Joop Schaye
Summary: Using the BAHAMAS cosmological simulations, it is shown that aperture masses are less sensitive to changes in mass caused by galaxy formation processes, making them a more accurate measure of galaxy cluster mass without loss of cosmological constraining power.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
Hiu Wing Wong, Ming-chung Chu
Summary: Massive cosmological neutrinos can smooth the large-scale structure in the universe and delay structure formation. N-body simulations involving neutrinos are used to measure the merger and mass accretion history of dark matter halos. It is found that non-zero neutrino masses delay the formation of halos within a certain range of virial mass, while non-zero neutrino asymmetry parameter has the opposite effect. The dependencies of these parameters also evolve with redshift.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2022)
Article
Astronomy & Astrophysics
Hao-Yi Wu, David H. Weinberg, Andres N. Salcedo, Benjamin D. Wibking
Summary: We predict constraints on the amplitude of matter clustering sigma(8)(z) achievable in current and next-generation weak lensing surveys through a combination of cluster weak lensing and number counts. An approach similar to galaxy-galaxy lensing is advocated, where observables in each redshift bin are the mean number counts and mean weak lensing profile of clusters above a mass proxy threshold.
ASTROPHYSICAL JOURNAL
(2021)
Article
Astronomy & Astrophysics
Alex Hall
Summary: The study investigates the constraints of Lambda cold dark matter parameters in weak lensing, improving upon previous studies through the use of the halo model. It explains the limited constraint on the Hubble constant by cosmic shear, and how degeneracies between parameters can be broken to achieve more accurate constraints. It also highlights the challenges in achieving strong constraints on the Hubble constant with upcoming lensing surveys.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
A. Campos, S. Samuroff, R. Mandelbaum
Summary: In this paper, an empirical approach to model selection is proposed, which balances parameter bias against model complexity. Synthetic data is used to calibrate the relationship between bias and the chi(2) difference between models, enabling the interpretation of chi(2) values obtained from real data and the selection of appropriate models. The method is applied to the problem of intrinsic alignments in cosmology, and the commonly used non-linear alignment (NLA) and tidal alignment and tidal torque (TATT) models are compared.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
Emily P. Longley, Chihway Chang, Christopher W. Walter, Joe Zuntz, Mustapha Ishak, Rachel Mandelbaum, Hironao Miyatake, Andrina Nicola, Eske M. Pedersen, Maria E. S. Pereira, Judit Prat, J. Sanchez, Lucas F. Secco, Tilman Troester, Michael Troxel, Angus H. Wright
Summary: Cosmological parameter constraints from recent galaxy imaging surveys have reached percent-level accuracy on the effective amplitude of the lensing signal, S-8. The upcoming LSST will provide subpercent level measurements of cosmological parameters, which will be a milestone test for the ?CDM model. A unified catalogue-level reanalysis of three cosmic shear data sets from DES-Y1, KiDS-1000, and HSC-Y1 shows that the S-8 constraint is robust and the three surveys are statistically consistent. Considering the cross-covariance between KiDS-1000 and HSC-Y1, the combined data sets yield a 1.6-1.9% constraint on S-8 under different assumptions.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
Giovanni Covone, Mauro Sereno
Summary: This article discusses the gravitational lensing phenomena that occur due to the redshift drift between the lensed source, gravitational lens, and observer. The proximity of the source to the drifting caustics can result in the occurrence or disappearance of a pair of images due to cosmological expansion. Lensing systems act as signal converters, altering the angular position, magnification, distortion, and time delay of existing multiple images.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
Bailey Robison, Michael J. Hudson, Jean-Charles Cuillandre, Thomas Erben, Sebastien Fabbro, Raphael Gavazzi, Axel Guinot, Stephen Gwyn, Hendrik Hildebrandt, Martin Kilbinger, Alan McConnachie, Lance Miller, Isaac Spitzer, Ludovic van Waerbeke
Summary: Using weak gravitational lensing, the ellipticity of dark matter haloes around Luminous Red Galaxies (LRGs) was measured. The results showed that for LRGs in the Sloan Digital Sky Survey Data Release 7 (DR7) with mass M~ 2.7 x 10^13 M_sun h^-1, the halo ellipticity was found to be e = 0.46 +/- 0.10, with f(h) = 2.2 +/- 0.6 as a fraction of the galaxy's ellipticity. For BOSS LRGs, the detection was marginally significant: e = 0.20 +/- 0.10 and f(h) = 0.7 +/- 0.7. These findings are consistent with previous measurements and suggest an increase in halo ellipticity of 0.10 +/- 0.06 per decade in halo mass.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
S. Samuroff, R. Mandelbaum, J. Blazek, A. Campos, N. MacCrann, G. Zacharegkas, A. Amon, J. Prat, S. Singh, J. Elvin-Poole, A. J. Ross, A. Alarcon, E. Baxter, K. Bechtol, M. R. Becker, G. M. Bernstein, A. Carnero Rosell, M. Carrasco Kind, R. Cawthon, C. Chang, R. Chen, A. Choi, M. Crocce, C. Davis, J. DeRose, S. Dodelson, C. Doux, A. Drlica-Wagner, K. Eckert, 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, P. Lemos, J. McCullough, J. Myles, A. Navarro-Alsina, S. Pandey, A. Porredon, M. Raveri, M. Rodriguez-Monroy, R. P. Rollins, A. Roodman, G. Rossi, E. S. Rykoff, C. Sanchez, L. F. Secco, I Sevilla-Noarbe, E. Sheldon, T. Shin, M. A. Troxel, I Tutusaus, N. Weaverdyck, B. Yanny, B. Yin, Y. Zhang, J. Zuntz, M. Aguena, O. Alves, J. Annis, D. Bacon, E. Bertin, S. Bocquet, D. Brooks, D. L. Burke, J. Carretero, M. Costanzi, L. N. da Costa, M. E. S. Pereira, J. De Vicente, S. Desai, H. T. Diehl, J. P. Dietrich, P. Doel, I Ferrero, B. Flaugher, J. Frieman, J. Garcia-Bellido, S. R. Hinton, D. L. Hollowood, K. Honscheid, D. J. James, K. Kuehn, O. Lahav, J. L. Marshall, P. Melchior, J. Mena-Fernandez, F. Menanteau, R. Miquel, J. Newman, A. Palmese, A. Pieres, A. A. Plazas Malagon, E. Sanchez, V Scarpine, M. Smith, E. Suchyta, M. E. C. Swanson, G. Tarle, C. To
Summary: We directly constrain galaxy intrinsic alignments (IAs) using data from Dark Energy Survey Year 3 (DES Y3), Extended Baryon Oscillation Spectroscopic Survey (eBOSS), and Baryon Oscillation Spectroscopic Survey (BOSS). Our measurements incorporate different types of galaxies at various redshifts and fit a model that includes lensing, magnification, and photometric redshift error. We detect IAs in each sample and observe a detectable dependence on color between broadly defined red samples. It is likely that future measurements will require a more sophisticated approach to account for the effects of color and luminosity on the IA signal.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
Patrick Shaw, Rupert A. C. Croft, R. Benton Metcalf
Summary: We evaluate the performance of the Lyman alpha forest weak gravitational lensing estimator on different types of forest data and investigate its dependence on spectrum signal to noise. The non-linearity and non-Gaussianity in the forest data cause a reduction in signal to noise, and using ray-traced potentials from N-body simulations incurs an additional reduction. We also demonstrate methods for mitigating these issues, such as Gaussianization and bias correction.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)