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Related papers: Weak Lensing the non-Linear Ly-alpha Forest

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We present a set of predictions for weak lensing correlation functions in the context of modified gravity models, including a prescription for the impact of the nonlinear power spectrum regime in these models. We consider the DGP and f(R)…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Emma Beynon , David J. Bacon , Kazuya Koyama

In paper I (Yu et al. [1]), we show through N-body simulation that a local monotonic Gaussian transformation can significantly reduce non-Gaussianity in a noise-free lensing convergence field. This makes the Gaussianization a promising…

Cosmology and Nongalactic Astrophysics · Physics 2012-07-17 Yu Yu , Pengjie Zhang , Weipeng Lin , Weiguang Cui , James N. Fry

We review recent developments in the theory of the Lyman-alpha forest and their implications for the role of the forest as a test of cosmological models. Simulations predict a relatively tight correlation between the local Lya optical depth…

Astrophysics · Physics 2009-11-07 David H. Weinberg , Romeel Dav'e , Neal Katz , Juna A. Kollmeier

The power spectrum of weak lensing fluctuations has a non-Gaussian distribution due to its quadratic nature. On small scales the Central Limit Theorem acts to Gaussianize this distribution but non-Gaussianity in the signal due to…

Cosmology and Nongalactic Astrophysics · Physics 2022-06-29 Alex Hall , Andy Taylor

We investigate the three-point correlation between the Lyman-$\alpha$ forest and the CMB weak lensing ($\delta_F \delta_F \kappa$) expressed as the cross-correlation between the CMB weak lensing field and local variations in the forest…

Cosmology and Nongalactic Astrophysics · Physics 2018-01-24 Chi-Ting Chiang , Anže Slosar

Estimators for weak lensing observables such as shear and convergence generally have non-linear corrections, which, in principle, make weak lensing power spectra sensitive to primordial non-Gaussianity. In this paper, we quantitatively…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-19 Donghui Jeong , Fabian Schmidt , Emiliano Sefusatti

The Lyman-alpha forest is a portion of the observed light spectrum of distant galactic nuclei which allows us to probe remote regions of the Universe that are otherwise inaccessible. The observed Lyman-alpha forest of a quasar light…

The Lyman alpha forest power spectrum has been measured on large scales by the BOSS survey in SDSS-III at $z\sim 2.3$, has been shown to agree well with linear theory predictions, and has provided the first measurement of Baryon Acoustic…

Cosmology and Nongalactic Astrophysics · Physics 2015-12-16 Andreu Arinyo-i-Prats , Jordi Miralda-Escudé , Matteo Viel , Renyue Cen

We use statistical inference theory to explore the constraints from future galaxy weak lensing (cosmic shear) surveys combined with the current CMB constraints on cosmological parameters, focusing particularly on the running of the spectral…

Astrophysics · Physics 2009-11-10 Mustapha Ishak , Christopher M. Hirata , Patrick McDonald , Uros Seljak

We study how well the Gaussian approximation is valid for computing the covariance matrices of the convergence power and bispectrum in weak gravitational lensing analyses. We focus on its impact on the cosmological parameter estimations by…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Masanori Sato , Takahiro Nishimichi

We present a framework for analyzing weak gravitational lensing survey data, including lensing and source-density observables, plus spectroscopic redshift calibration data. All two-point observables are predicted in terms of parameters of a…

Astrophysics · Physics 2014-11-18 Gary M. Bernstein

We investigate the signature of primordial non-Gaussianities in the weak lensing bispectrum, in particular the signals generated by local, orthogonal and equilateral non-Gaussianities. The questions we address include the signal-to-noise…

Cosmology and Nongalactic Astrophysics · Physics 2013-03-07 Bjoern Malte Schaefer , Alessandra Grassi , Mischa Gerstenlauer , Christian T. Byrnes

We explore possibility of using the three dimensional bispectra of the Ly-alpha forest and the redshifted 21-cm signal from the post-reionization epoch to constrain primordial non-Gaussianity. Both these fields map out the large scale…

Cosmology and Nongalactic Astrophysics · Physics 2013-04-04 Tapomoy Guha Sarkar , Dhiraj Kumar Hazra

Deep learning (DL) has been shown to outperform traditional, human-defined summary statistics of the Ly{\alpha} forest in constraining key astrophysical and cosmological parameters owing to its ability to tap into the realm of non-Gaussian…

Instrumentation and Methods for Astrophysics · Physics 2025-10-24 Parth Nayak , Michael Walther , Daniel Gruen

In this article we present an analytic calculation of the probability distribution of the magnification of distant sources due to weak gravitational lensing from non-linear scales. We use a realistic description of the non-linear density…

Astrophysics · Physics 2011-05-23 P. Valageas

The highly anisotropic nature of the Lyman-alpha (Ly$\alpha$) forest data introduces a complex survey window function that complicates the measurement of the three-dimensional power spectrum ($P_{\mathrm{3D}}$). In this paper, we present…

Cosmology and Nongalactic Astrophysics · Physics 2025-06-19 N. G. Karaçaylı , C. M. Hirata

The next generation of weak gravitational lensing surveys has the potential to place stringent constraints on cosmological parameters. However, their analysis is limited by systematics such as the intrinsic alignments of galaxies, which…

Cosmology and Nongalactic Astrophysics · Physics 2025-04-18 Max E. Lee , Zoltán Haiman , Shivam Pandey , Shy Genel

We study the lensing convergence power spectrum and its covariance for a standard LCDM cosmology. We run 400 cosmological N-body simulations and use the outputs to perform a total of 1000 independent ray-tracing simulations. We compare the…

Cosmology and Nongalactic Astrophysics · Physics 2012-03-12 Masanori Sato , Takashi Hamana , Ryuichi Takahashi , Masahiro Takada , Naoki Yoshida , Takahiko Matsubara , Naoshi Sugiyama

We investigate the detection prospects for gravitational lensing of three-dimensional maps from upcoming line intensity surveys, focusing in particular on the impact of gravitational nonlinearities on standard quadratic lensing estimators.…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-05 Simon Foreman , P. Daniel Meerburg , Alexander van Engelen , Joel Meyers

We compute statistical properties of weak gravitational lensing by large-scale structure in three Cold Dark Matter models. We use a P$^3$M $N$-body code to simulate the formation and evolution of large-scale structure in the universe. We…

Astrophysics · Physics 2009-10-31 Takashi Hamana , Hugo Martel , Toshifumi Futamase