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We present a novel strategy to uncover indirect signs of new physics in collider data using the Standard Model Effective Field Theory (SMEFT) framework, offering notably improved sensitivity compared to traditional global analyses. Our…

High Energy Physics - Phenomenology · Physics 2025-11-25 Martin Hirsch , Luca Mantani , Veronica Sanz

We investigate biases induced by the conversion between the observed image shape to shear distortion in current weak lensing analysis methods. Such overall calibration biases cannot be detected by the standard tests such as E/B…

Astrophysics · Physics 2009-11-07 Christopher M. Hirata , Uros Seljak

We demonstrate that the maximum-entropy method for gravitational lens reconstruction presented in Bridle et al. (1998) may be applied even when only shear \emph{or} magnification information is present. We also demonstrate that the method…

Astrophysics · Physics 2007-05-23 S. L. Bridle , M. P. Hobson , Richard Saunders , A. N. Lasenby

We investigate the impact of point spread function (PSF) fitting errors on cosmic shear measurements using the concepts of complexity and sparsity. Complexity, introduced in a previous paper, characterizes the number of degrees of freedom…

Instrumentation and Methods for Astrophysics · Physics 2015-05-13 S. Paulin-Henriksson , A. Refregier , A. Amara

A main science goal for the Large Synoptic Survey Telescope (LSST) is to measure the cosmic shear signal from weak lensing to extreme accuracy. One difficulty, however, is that with the short exposure time ($\simeq$15 seconds) proposed, the…

Exploiting the full statistical power of future cosmic shear surveys will necessitate improvements to the accuracy with which the gravitational lensing signal is measured. We present a framework for calibrating shear with image simulations…

We have developed a new three-dimensional algorithm, based on the standard P$^3$M method, for computing deflections due to weak gravitational lensing. We compare the results of this method with those of the two-dimensional planar approach,…

Astrophysics · Physics 2009-10-31 H. M. P. Couchman , Andrew J. Barber , Peter A. Thomas

We show, using the pseudo-$C_\ell$ technique, how to estimate cosmic shear and galaxy-galaxy lensing power spectra that are insensitive to the effects of multiple sources of lensing bias including source-lens clustering, magnification bias…

Cosmology and Nongalactic Astrophysics · Physics 2025-08-12 Christopher A. J. Duncan , Michael L. Brown

We derive a new relation between cosological distances, valid in any (statistically) isotropic space-time and independent of cosmological parameters or even the validity of the field equation of General Relativity. In particular, this…

Cosmology and Nongalactic Astrophysics · Physics 2016-08-03 Peter Schneider

We apply the Fourier Power Function Shapelets (FPFS) shear estimator to the first year data of the Hyper Suprime-Cam survey to construct a shape catalog. The FPFS shear estimator has been demonstrated to have multiplicative bias less than…

Cosmology and Nongalactic Astrophysics · Physics 2021-02-19 Xiangchong Li , Masamune Oguri , Nobuhiko Katayama , Wentao Luo , Wenting Wang , Jiaxin Han , Hironao Miyatake , Keigo Nakamura , Surhud More

We present a new method to extract cosmological constraints from weak lensing (WL) peak counts, which we denote as `the hierarchical algorithm'. The idea of this method is to combine information from WL maps sequentially smoothed with a…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Laura Marian , Robert E. Smith , Stefan Hilbert , Peter Schneider

Large scale datasets created from user labels or openly available data have become crucial to provide training data for large scale learning algorithms. While these datasets are easier to acquire, the data are frequently noisy and…

Computer Vision and Pattern Recognition · Computer Science 2019-04-18 Rodrigo Caye Daudt , Bertrand Le Saux , Alexandre Boulch , Yann Gousseau

The measurement of cosmic shear using weak gravitational lensing is a challenging task that involves a number of complicated procedures. We study in detail the systematic errors in the measurement of weak lensing Minkowski Functionals…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 Masato Shirasaki , Naoki Yoshida

We present a method to measure the growth of structure and the background geometry of the Universe -- with no a priori assumption about the underlying cosmological model. Using Canada-France-Hawaii Lensing Survey (CFHTLenS) shear data we…

Cosmology and Nongalactic Astrophysics · Physics 2019-04-12 Peter L. Taylor , Thomas D. Kitching , Jason D. McEwen

The abundance of peaks in weak gravitational lensing maps is a potentially powerful cosmological tool, complementary to measurements of the shear power spectrum. We study peaks detected directly in shear maps, rather than convergence maps,…

Cosmology and Nongalactic Astrophysics · Physics 2015-09-16 Nicolas Martinet , James G. Bartlett , Alina Kiessling , Barbara Sartoris

Cosmic shear is the distortion of images of distant galaxies due to weak gravitational lensing by the large-scale structure in the Universe. Such images are coherently deformed by the tidal field of matter inhomogeneities along the line of…

Cosmology and Nongalactic Astrophysics · Physics 2015-07-22 Martin Kilbinger

We show how to enhance the redshift accuracy of surveys consisting of tracers with highly uncertain positions along the line of sight. Photometric surveys with redshift uncertainty delta_z ~ 0.03 can yield final redshift uncertainties of…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Jens Jasche , Benjamin D. Wandelt

We present a field-based approach to the analysis of cosmic shear data to infer jointly cosmological parameters and the dark matter distribution. This forward modelling approach samples the cosmological parameters and the initial matter…

Cosmology and Nongalactic Astrophysics · Physics 2021-11-17 Natalia Porqueres , Alan Heavens , Daniel Mortlock , Guilhem Lavaux

Modeling the Point Spread Function (PSF) of wide-field surveys is vital for many astrophysical applications and cosmological probes including weak gravitational lensing. The PSF smears the image of any recorded object and therefore needs to…

Instrumentation and Methods for Astrophysics · Physics 2018-07-26 Jörg Herbel , Tomasz Kacprzak , Adam Amara , Alexandre Refregier , Aurelien Lucchi

We investigate the sensitivity to the effects of lensing magnification on large-scale structure analyses combining photometric cosmic shear and galaxy clustering data (i.e. the now commonly called "3$\times$2-point" analysis). Using a…

Cosmology and Nongalactic Astrophysics · Physics 2020-01-08 Leander Thiele , Christopher A. J. Duncan , David Alonso