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We demonstrate a method for reconstructing the weak lensing potential from the Lyman-$\alpha$ forest data. We derive an optimal estimator for the lensing potential on the sky based on the correlation between pixels in real space. This…

Cosmology and Nongalactic Astrophysics · Physics 2020-10-21 R. Benton Metcalf , Nicolas Tessore , Rupert A. C. Croft

We investigate the large-scale inhomogeneities of the hydrogen ionizing radiation field in the Universe at redshift z=3. Using a raytracing algorithm, we simulate a model in which quasars are the dominant sources of radiation. We make use…

Astrophysics · Physics 2009-11-10 Rupert A. C. Croft

Lyman-alpha forest lines in QSO spectra have typical widths of 20-50 km/s. Low column density absorbers in cosmological simulations are large, diffuse structures, and the Hubble flow across the spatially extended absorber is usually the…

Astrophysics · Physics 2007-05-23 David H. Weinberg , Lars Hernquist , Neal Katz , Rupert Croft , Jordi Miralda-Escudé

Interpreting observations of the Lyman-$\alpha$ forest flux power spectrum requires interpolation between a small number of expensive simulations. We present a Gaussian process emulator modelling the 1D flux power spectrum as a function of…

Cosmology and Nongalactic Astrophysics · Physics 2021-05-17 Christian Pedersen , Andreu Font-Ribera , Keir K. Rogers , Patrick McDonald , Hiranya V. Peiris , Andrew Pontzen , Anže Slosar

Current analyses of the Lyman-alpha forest assume that the primordial power spectrum of density perturbations obeys a simple power law, a strong theoretical assumption which should be tested. Employing a large suite of numerical simulations…

Cosmology and Nongalactic Astrophysics · Physics 2010-05-24 Simeon Bird

The Lyman-$\alpha$ forest is a highly non-linear field with a lot of information available in the data beyond the power spectrum. The flux probability distribution function (PDF) has been used as a successful probe of small-scale physics.…

Cosmology and Nongalactic Astrophysics · Physics 2017-10-18 Agnieszka M. Cieplak , Anže Slosar

We use LUQAS, a sample of 27 high resolution high signal-to-noise UVES quasar (QSO) spectra (Kim et al. 2004), and the Croft et al. (2002) sample together with a set of high resolution large box size hydro-dynamical simulations run with the…

Astrophysics · Physics 2009-11-11 Matteo Viel

Visualizing the high-redshift Universe is difficult due to the dearth of available data; however, the Lyman-alpha forest provides a means to map the intergalactic medium at redshifts not accessible to large galaxy surveys. Large-scale…

Instrumentation and Methods for Astrophysics · Physics 2015-06-18 Jessi Cisewski , Rupert A. C. Croft , Peter E. Freeman , Christopher R. Genovese , Nishikanta Khandai , Melih Ozbek , Larry Wasserman

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

We investigate the promise of the Ly-alpha forest for high precision cosmology in the era of the Sloan Digital Sky Survey using low order N-point statistics. We show that with the existing data one can determine the amplitude, slope and…

Astrophysics · Physics 2009-11-07 R. Mandelbaum , P. McDonald , U. Seljak , R. Cen

The Lyman-$\alpha$ (Ly$\alpha$) three-dimensional correlation functions have been widely used to perform cosmological inference using the baryon acoustic oscillation (BAO) scale. While the traditional inference approach employs a data…

Cosmology and Nongalactic Astrophysics · Physics 2024-02-15 Francesca Gerardi , Andrei Cuceu , Benjamin Joachimi , Seshadri Nadathur , Andreu Font-Ribera

The squeezed-limit bispectrum, which is generated by nonlinear gravitational evolution as well as inflationary physics, measures the correlation of three wavenumbers, in the configuration where one wavenumber is much smaller than the other…

Cosmology and Nongalactic Astrophysics · Physics 2017-06-28 Chi-Ting Chiang , Agnieszka M. Cieplak , Fabian Schmidt , Anže Slosar

We present the first simulation of the signature of baryonic acoustic oscillations (BAO) in Lyman alpha forest data containing 180,000 mock quasar sight-lines. We use eight large dark-matter only simulations onto which we paint the Lyman…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-09 Anže Slosar , Shirley Ho , Martin White , Thibaut Louis

We present an analysis of high-resolution N-body simulations of decaying dark matter cosmologies focusing on the statistical properties of the transmitted Lyman-alpha forest flux in the high-redshift intergalactic medium. In this type of…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Mei-Yu Wang , Rupert A. C. Croft , Annika H. G. Peter , Andrew R. Zentner , Chris W. Purcell

We investigate correlations between the long wavelength fluctuations and the small scale power in the Lyman alpha forest. We show that such correlations can be used to discriminate between fluctuations induced by large scale structure and…

Astrophysics · Physics 2009-10-31 Matias Zaldarriaga , Uros Seljak , Lam Hui

Studying the matter distribution in the universe through the Lyman-$\alpha$ forest allows us to constrain small-scale physics in the high-redshift regime. Spectroscopic quasar surveys are generating increasingly large datasets that require…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-23 Josue De-Santiago , Rafael Gutiérrez-Balboa , Gustavo Niz , Alma X. González-Morales

We provide a perturbative effective field theory (EFT) description for anisotropic (redshift-space) correlations between the Lyman alpha forest and a generic biased tracer of matter, which could be represented by quasars, high-redshift…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-23 Anton Chudaykin , Mikhail M. Ivanov

In this work, we analyze the Lyman-$\alpha$ forest in cosmological hydrodynamical simulations of chameleon-type f(R) gravity with the goal to assess whether the impact of such models is detectable in absorption line statistics. We carry out…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-23 Christian Arnold , Ewald Puchwein , Volker Springel