As observational evidence increasingly consolidates the case for a cosmological constant being the source of the Universe's accelerated expansion, the question whether, and if so, how well, future experiments could detect deviations from this standard scenario is raised with urgency. Assuming a dark energy component different from a cosmological constant, the observable effects in general include gravitational clustering described by the fluid's (rest-frame) speed of sound. We employ 3d weak cosmic shear, a proposed method to take advantage of the full three-dimensional information inherent to the cosmic shear field, to explore the capability of future surveys to detect dark energy clustering and the signature of an enhanced amplitude of the matter power spectrum on large scales. For this purpose, we present adequate numerical methods facilitating 3d weak cosmic shear calculations. We find that the possible constraints heavily depend on the dark energy equation of state w. If w is not very close to -1, constraining the squared sound speed within an order of magnitude seems possible with a combination of Euclid and Planck data.
A systematic study of projection biases in the Weak Lensing analysis of cosmic shear and the combination of galaxy clustering and galaxy-galaxy lensing
Cosmic Shear constraints from HSC Year 3 with clustering calibration of the tomographic redshift distributions from DESI
Lawrence Berkeley National Laboratory（劳伦斯伯克利国家实验室）；University of California, Berkeley（加州大学伯克利分校）；Institute for Advanced Study（普林斯顿高等研究院）；University of Virginia（弗吉尼亚大学）；University of Pittsburgh（匹兹堡大学）
In the near future, the overlap of the Rubin Observatory Legacy Survey of Space and Time (LSST) and the Simons Observatory (SO) will present an ideal opportunity for joint cosmological dataset analyses. In this paper we simulate the joint likelihood analysis of these two experiments using six two-point functions derived from galaxy position, galaxy shear, and CMB lensing convergence fields. Our analysis focuses on realistic noise and systematics models and we find that the dark energy Figure-of-Merit (FoM) increases by 53% (92%) from LSST-only to LSST+SO in Year 1 (Year 6). We also investigate…
Exploring Joint Observation of the CSST Shear and clustering of astrophysical gravitational wave source measurements
National Astronomical Observatories, Chinese Academy of Sciences（中国科学院国家天文台）；School of Astronomy and Space Sciences, University of Chinese Academy of Sciences(UCAS)（中国科学院大学天文与空间科学学院）
Joint constraints from cosmic shear, galaxy-galaxy lensing and galaxy clustering: internal tension as an indicator of intrinsic alignment modelling error
China Space Station Telescope (CSST) is a forthcoming powerful Stage IV space-based optical survey equipment. It is expected to explore a number of important cosmological problems in extremely high precision. In this work, we focus on investigating the constraints on neutrino mass and other cosmological parameters under the model of cold dark matter with a constant equation of state of dark energy ($w$CDM), using the mock data from the CSST photometric galaxy clustering and cosmic shear surveys (i.e. 3$\times$2pt). The systematics from galaxy bias, photometric redshift uncertainties, intrinsic…
Non-linear infusion of intrinsic alignment and source clustering: impact on non-Gaussian cosmic shear statistics
Newcastle University（纽卡斯尔大学）；Duke University（杜克大学）；The University of Texas at Dallas（德克萨斯大学达拉斯分校）；Kavli IPMU (WPI), UTIAS, The University of Tokyo（东京大学 Kavli宇宙物理数学联合研究所（WPI）、UTIAS）；Center for Data-Driven Discovery (CD3), UTIAS, The University of Tokyo（东京大学 UTIAS 数据驱动发现中心（CD3））；Ludwig-Maximilians-Universität（慕尼黑大学）；Northeastern University（东北大学）；Universität Bielefeld（比勒费尔德大学）
We present weak lensing shear catalogues from the fourth data release of the Kilo-Degree Survey, KiDS-1000, spanning 1006 square degrees of deep and high-resolution imaging. Our `gold-sample' of galaxies, with well-calibrated photometric redshift distributions, consists of 21 million galaxies with an effective number density of $6.17$ galaxies per square arcminute. We quantify the accuracy of the spatial, temporal, and flux-dependent point-spread function (PSF) model, verifying that the model meets our requirements to induce less than a $0.1σ$ change in the inferred cosmic shear constraints on…
Cosmic Shear in Effective Field Theory at Two-Loop Order: Revisiting $S_8$ in Dark Energy Survey Data
Columbia University（哥伦比亚大学）；NASA Hubble Fellowship Program（NASA哈勃学者计划）；Brookhaven National Laboratory（布鲁克海文国家实验室）；Lawrence Berkeley National Laboratory（劳伦斯伯克利国家实验室）；Center for Theoretical Physics – a Leinweber Institute, Massachusetts Institute of Technology（麻省理工学院莱因韦伯理论物理中心）；The NSF AI Institute for Artificial Intelligence and Fundamental Interactions（NSF人工智能基础相互作用研究所）；Leinweber Institute for Theoretical Physics at Stanford（斯坦福大学莱因韦伯理论物理研究所）；Kavli Institute for Particle Astrophysics and Cosmology（卡弗里粒子天体物理学与宇宙学研究所）
The magnification of galaxies in modern galaxy surveys induces additional correlations in the cosmic shear, galaxy-galaxy lensing and clustering observables used in modern lensing "3x2pt" analyses, due to sample selection. In this paper, we emulate the magnification contribution to all three observables utilising the SLICS simulations suite, and test the sensitivity of the cosmological model, galaxy bias and redshift distribution calibration to un-modelled magnification in a Stage-IV-like survey using Monte-Carlo sampling. We find that magnification cannot be ignored in any single or combined …
Maximising the information that can be extracted from weak lensing measurements is a key goal for upcoming surveys such as LSST and Euclid. This is typically achieved through statistics that are complementary to the cosmic shear two-point correlation function, the most well established of which is the weak lensing peak abundance. In this work, we study the clustering of weak lensing peaks, and present parameter constraint forecasts for an LSST-like survey. We use the cosmoslics $w$CDM simulations to measure the peak two-point correlation function for a range of cosmological parameters, and use…
We investigate the inclusion of clustering maps in a weak lensing Minkowski functional (MF) analysis of DES-like and LSST-like simulations to constrain cosmological parameters. The standard 3x2pt approach to lensing and clustering data uses two-point correlations as its primary statistic; MFs, morphological statistics describing the shape of matter fields, provide additional information for non-Gaussian fields. Previous analyses have studied MFs of lensing convergence maps; in this project we explore their simultaneous application to clustering maps. We employ a simplified linear galaxy bias m…
I present a new technique for the measurement of the growth of cosmic structures via the power spectrum of weak lensing cosmic shear. It is based on a template-fitting approach, where a redshift-dependent amplitude of lensing modulates a fixed template power spectrum. Such an amplitude, which is promoted to a free parameter and fit against tomographic cosmic shear data, reads $D(z)\,σ_8\,Ω_{{\rm m},0}=:Ωσ_8(z)$, with $D(z)$ the growth factor, $σ_8$ a proxy for the overall amplitude of the matter power spectrum, and $Ω_{{\rm m},0}$ the present-day matter abundance. I show that this method is ab…
We investigate the importance of lensing magnification for estimates of galaxy clustering and its cross-correlation with shear for the photometric sample of Euclid. Using updated specifications, we study the impact of lensing magnification on the constraints and the shift in the estimation of the best fitting cosmological parameters that we expect if this effect is neglected. We follow the prescriptions of the official Euclid Fisher matrix forecast for the photometric galaxy clustering analysis and the combination of photometric clustering and cosmic shear. The slope of the luminosity function…
We quantify the cosmological constraining power of the `lensing PDF' - the one-point probability density of weak lensing convergence maps - by modelling this statistic numerically with an emulator trained on $w$CDM cosmic shear simulations. After validating our methods on Gaussian and lognormal fields, we show that `multi-scale' PDFs - measured from maps with multiple levels of smoothing - offer considerable gains over two-point statistics, owing to their ability to extract non-Gaussian information: for a mock Stage-III survey, lensing PDFs yield 33\% tighter constraints on the clustering para…
Lensing without mixing: Probing baryonic acoustic oscillations and other scale-dependent features in cosmic shear surveys
Université Paris-Saclay（巴黎萨克雷大学）；CNRS（法国国家科学研究中心）；CEA（法国原子能和替代能源委员会）；Institut de physique théorique（理论物理研究所）；Université Paris Cité（巴黎西岱大学）；AIM（天体物理、物质与辐射研究所）
Recent works have shown that weak lensing magnification must be included in upcoming large-scale structure analyses, such as for the Vera C. Rubin Observatory Legacy Survey of Space and Time (LSST), to avoid biasing the cosmological results. In this work we investigate whether including magnification has a positive impact on the precision of the cosmological constraints, as well as being necessary to avoid bias. We forecast this using an LSST mock catalog and a halo model to calculate the galaxy power spectra. We find that including magnification has little effect on the precision of the cosmo…
Blast.jl: Differentiable Non-Limber Power Spectra for Joint Clustering, Shear, and CMB lensing Analyses
Waterloo Centre for Astrophysics, University of Waterloo（滑铁卢大学天体物理中心）；Department of Physics and Astronomy, University of Waterloo（滑铁卢大学物理与天文系）；Perimeter Institute for Theoretical Physics（理论物理前沿研究所）；Dipartimento di Fisica, Università degli Studi di Torino（都灵大学物理系）；INFN – Istituto Nazionale di Fisica Nucleare, Sezione di Torino（意大利国家核物理研究所都灵分部）；INAF – Istituto Nazionale di Astrofisica, Osservatorio Astrofisico di Torino（意大利国家天体物理研究所都灵天文台）；Department of Physics & Astronomy, University of the Western Cape（西开普大学物理与天文系）；Université Paris-Saclay（巴黎萨克雷大学）；CIEMAT（西班牙能源、环境和工业技术研究中央实验室）；California Institute of Technology（加州理工学院）
