Results 1 to 10 of about 33,635 (203)

Ellipsoidal Universe and Cosmic Shear

Universe
We consider a Bianchi I geometry of the universe. We obtain a cosmic shear expression related to the eccentricity of the universe. In particular, we study the connections among cosmic shear, eccentricity, and CMB.
Luigi Tedesco
doaj   +5 more sources

Cosmic shear surveys [PDF]

, 2001
Gravitational weak shear produced by large-scale structures of the universe induces a correlated ellipticity distribution of distant galaxies. The amplitude and evolution with angular scale of the signal depend on cosmological models and can be inverted ...
., Bernardeau, F., Erben, T., Fort, B., Jain, B., Maoli, R., Mellier, Y., Schneider, P., van Waerbeke, L.   +8 more
core   +3 more sources

Mapping Spatially Varying Additive Biases in Cosmic Shear Data

The Open Journal of Astrophysics, 2021
In this paper we address the challenge of extracting maps of spatially varying unknown additive biases from cosmic shear data. This is done by exploiting the isotropy of the cosmic shear field, and the anisotropy of a typical additive bias field, using ...
Thomas Kitching, Anurag C. Deshpande, P. L. Taylor   +2 more
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Source Distributions of Cosmic Shear Surveys in Efficiency Space

The Open Journal of Astrophysics, 2020
We show that the lensing efficiency of cosmic shear generically has a simple shape, even in the case of a tomographic survey with badly behaved photometric redshifts.
Nicolas Tessore, Ian Harrison
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The Impact of Quadratic Biases on Cosmic Shear

The Open Journal of Astrophysics, 2022
In this paper we revisit potential biases in cosmic shear power spectra caused by bias terms that multiply up to quadratic powers of the shear. Expanding the multiplicative bias field as a series of independent spin-$s$ fields we find terms $m_s$ that ...
Thomas D. Kitching, Anurag C. Deshpande
doaj   +2 more sources

Propagating Residual Biases in Cosmic Shear Power Spectra

The Open Journal of Astrophysics, 2019
In this paper we derive a full expression for the propagation of multiplicative and additive shape measurement biases into the cosmic shear power spectrum.
Thomas D. Kitching, Paniez Paykari, Henk Hoekstra, Mark Cropper   +3 more
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Categorizing models using Self-Organizing Maps: an application to modified gravity theories probed by cosmic shear

The Open Journal of Astrophysics, 2023
We propose to use Self-Organizing Maps (SOM) to map the impact of physical models onto observables. Using this approach, we are able to determine how theories relate to each other given their signatures.
Agnès Ferté, Shoubaneh Hemmati, Daniel Masters, Brigitte Montminy, Peter L. Taylor, Eric Huff, Jason Rhodes   +6 more
doaj   +1 more source

A tilt instability in the cosmological principle

European Physical Journal C: Particles and Fields, 2023
We show that the Friedmann–Lemaître–Robertson–Walker (FLRW) framework has an instability towards the growth of fluid flow anisotropies, even if the Universe is accelerating. This flow (tilt) instability in the matter sector is invisible to Cosmic No-Hair
Chethan Krishnan, Ranjini Mondol, M. M. Sheikh-Jabbari   +2 more
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Propagating residual biases in masked cosmic shear power spectra

The Open Journal of Astrophysics, 2020
In this paper we derive a full expression for the propagation of weak lensing shape measurement biases into cosmic shear power spectra including the effect of missing data.
Thomas D. Kitching, Anurag C. Deshpande, Peter L. Taylor   +2 more
doaj   +2 more sources

DES Y3 + KiDS-1000: Consistent cosmology combining cosmic shear surveys

The Open Journal of Astrophysics, 2023
We present a joint cosmic shear analysis of the Dark Energy Survey (DES Y3) and the Kilo-Degree Survey (KiDS-1000) in a collaborative effort between the two survey teams.
T.M.C. Abbott, M. Aguena, A. Alarcon, O. Alves, A. Amon, F. Andrade-Oliveira, M. Asgari, S. Avila, D. Bacon, K. Bechtol, M. R. Becker, G. M. Bernstein, E. Bertin, M. Bilicki, J. Blazek, S. Bocquet, D. Brooks, P. Burger, D. L. Burke, H. Camacho, A. Campos, A. Carnero Rosell, M. Carrasco Kind, J. Carretero, F. J. Castander, R. Cawthon, C. Chang, R. Chen, A. Choi, C. Conselice, J. Cordero, M. Crocce, L. N. da Costa, M. E. da Silva Pereira, R. Dalal, C. Davis, J. T. A. de Jong, J. DeRose, S. Desai, H. T. Diehl, S. Dodelson, P. Doel, C. Doux, A. Drlica-Wagner, A. Dvornik, K. Eckert, T. F. Eifler, J. Elvin-Poole, S. Everett, X. Fang, I. Ferrero, A. Ferté, B. Flaugher, O. Friedrich, J. Frieman, J. García-Bellido, M. Gatti, G. Giannini, B. Giblin, D. Gruen, R. A. Gruendl, G. Gutierrez, I. Harrison, W. G. Hartley, K. Herner, C. Heymans, H. Hildebrandt, S. R. Hinton, H. Hoekstra, D. L. Hollowood, K. Honscheid, H. Huang, E. M. Huff, D. Huterer, D. J. James, M. Jarvis, N. Jeffrey, T. Jeltema, B. Joachimi, S. Joudaki, A. Kannawadi, E. Krause, K. Kuehn, K. Kuijken, N. Kuropatkin, O. Lahav, P.-F. Leget, P. Lemos, S.-S. Li, X. Li, A. R. Liddle, M. Lima, C.-A. Lin, H. Lin, N. MacCrann, C. Mahony, J. L. Marshall, J. McCullough, J. Mena-Fernández, F. Menanteau, R. Miquel, J. J. Mohr, J. Muir, J. Myles, N. Napolitano, A. Navarro-Alsina, R. L. C. Ogando, A. Palmese, S. Pandey, Y. Park, M. Paterno, J. A. Peacock, D. Petravick, A. Pieres, A. A. Plazas Malagón, A. Porredon, J. Prat, M. Radovich, M. Raveri, R. Reischke, N. C. Robertson, R. P. Rollins, A. K. Romer, A. Roodman, E. S. Rykoff, S. Samuroff, C. Sánchez, E. Sanchez, J. Sanchez, P. Schneider, L. F. Secco, I. Sevilla-Noarbe, H.-Y. Shan, E. Sheldon, T. Shin, C. Sifón, M. Smith, M. Soares-Santos, B. Stölzner, E. Suchyta, M. E. C. Swanson, G. Tarle, D. Thomas, C. To, M. A. Troxel, T. Tröster, I. Tutusaus, J. L. van den Busch, T. N. Varga, A. R. Walker, N. Weaverdyck, R. H. Wechsler, J. Weller, P. Wiseman, A. H. Wright, B. Yanny, B. Yin, M. Yoon, Y. Zhang, J. Zuntz   +159 more
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