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We investigate Lyman-alpha forest flux statistics in mixed fuzzy dark matter (FDM) and cold dark matter (CDM) cosmologies using the Fluctuating Gunn-Peterson Approximation (FGPA) applied to hybrid Schr\"odinger-Poisson and N-body…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-08 Yourong Frank Wang

The spectrum of the quasar Q0055-269 ($z=3.66$) has been observed at the resolution of 14 km s$^{-1}$ in the wavelength interval 4750--6300 \AA. We give a list of Lyman$-\alpha$ lines and metal-line systems for which column densities and…

Astrophysics · Physics 2015-06-24 S. Cristiani , S. D'Odorico , A. Fontana , E. Giallongo , S. Savaglio

We investigate the spectral distribution of large sample covariance matrices with independent columns and entries in the columns that stem from Markov chains. We characterize the limiting spectral densities by their moments.…

Probability · Mathematics 2012-03-19 Olga Friesen , Matthias Löwe

We present a method to make predictions with sets of correlated data values, in this case QSO flux spectra. We predict the continuum in the Lyman-Alpha forest of a QSO, from 1020 -- 1216 A, using the spectrum of that QSO from 1216 -- 1600 A…

Astrophysics · Physics 2009-11-10 Nao Suzuki , David Tytler , David Kirkman , John M. O'Meara , Dan Lubin

The Ly$\alpha$ forest, a series of HI absorption lines in the quasar spectra, is a powerful tool for probing the large-scale structure of the intergalactic medium. Its three-dimensional (3D) correlation and cross-correlations with quasars…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-23 Koichiro Nakashima , Atsushi J. Nishizawa , Kentaro Nagamine , Yuri Oku , Ikkoh Shimizu

I analyze the density perturbations in a cosmological model with a scalar field coupled to ordinary matter, such as one obtains in string theory and in conformally transformed scalar-tensor theories. The spectrum of multipoles on the last…

Astrophysics · Physics 2008-11-26 Luca Amendola

For the purpose of studying the properties of heavy-elements associated with the Lyman-$\alpha$\ forest, we observed the gravitational lens Q1422+2309. We used the HIRES instrument on the W.M. Keck telescope to obtain a high-resolution,…

Astrophysics · Physics 2016-01-27 D. S. Womble , W. L. W. Sargent , R. S. Lyons

We present a comparison between the observed properties of damped Lyman alpha systems (DLAs) and the predictions of simple models for the evolution of present day disk galaxies, including both low and high surface brightness galaxies. We…

Astrophysics · Physics 2008-11-26 Samuel Boissier , Celine Peroux , Max Pettini

The Lyman-alpha forest is a unique probe of large-scale matter density fluctuations at high redshift (z > 2). It is possible to obtain 3D maps of the matter distribution from Lyman-alpha data, using tomographic reconstruction methods. Here,…

Cosmology and Nongalactic Astrophysics · Physics 2022-03-16 Corentin Ravoux

In this article we investigate the energy spectrum statistics of fractals at the quantum level. We show that the energy-level distribution of a fractal follows a power-law behaviour, if its energy spectrum is a limit set of piece-wise…

Disordered Systems and Neural Networks · Physics 2019-02-06 Askar A. Iliasov , Mikhail I. Katsnelson , Shengjun Yuan

We combine the Ly-alpha forest power spectrum (LYA) from the Sloan Digital Sky Survey (SDSS) and high resolution spectra with cosmic microwave background (CMB) including 3-year WMAP, and supernovae (SN) and galaxy clustering constraints to…

Astrophysics · Physics 2009-11-11 Uros Seljak , Anze Slosar , Patrick McDonald

The correlation between neutron skin-thickness of a neutron-rich nucleus and slope parameter of symmetry energy is assessed as a function of density using relativistic mean field models containing non-linear couplings among different…

Nuclear Theory · Physics 2022-04-06 Chiranjib Mondal

Ecological communities exhibit pervasive patterns and inter-relationships between size, abundance, and the availability of resources. We use scaling ideas to develop a unified, model-independent framework for understanding the distribution…

Statistical Mechanics · Physics 2015-05-18 Filippo Simini , Tommaso Anfodillo , Marco Carrer , Jayanth R. Banavar , Amos Maritan

We investigate the cross-correlation signal between 21cm intensity mapping maps and the Lyman-alpha forest in the fully non-linear regime using state-of-the-art hydrodynamic simulations. The cross-correlation signal between these fields can…

Cosmology and Nongalactic Astrophysics · Physics 2017-04-06 Isabella P. Carucci , Francisco Villaescusa-Navarro , Matteo Viel

The bulk of recent cosmological research has focused on the adiabatic cold dark matter model and its simple extensions. Here we present an accurate fitting formula that describes the matter transfer functions of all common variants,…

Astrophysics · Physics 2009-10-30 Daniel J. Eisenstein , Wayne Hu

(abridged) We present an effective implementation of analytical calculations of the Lyalpha opacity distribution of the Intergalactic Medium (IGM) along multiple lines of sight (LOS) to distant quasars in a cosmological setting. This method…

Astrophysics · Physics 2009-11-06 M. Viel , S. Matarrese , H. J. Mo , M. G. Haehnelt , Tom Theuns

We calculate the column density distribution of damped Lyman alpha systems, modeled as spherical isothermal gaseous halos ionized by the external cosmic background. The effects of self-shielding introduce a hump in this distribution, at a…

Astrophysics · Physics 2009-11-07 Zheng Zheng , Jordi Miralda-Escude

Spectroscopy of QSO absorption lines provides essential observational input for the study of nucleosynthesis and chemical evolution of galaxies at high redshift. But new observations may indicate that present chemical abundance data are…

Astrophysics · Physics 2007-05-23 R. Quast , D. Reimers , A. Smette , O. Garcet , C. Ledoux , S. Lopez , L. Wisotzki

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

Observed power spectrum of matter found in Papers I and II is compared with analytical power spectra. Spatially flat cold and mixed dark matter models with cosmological constant and open models are considered. The primordial power spectrum…

Astrophysics · Physics 2009-10-31 J. Einasto , M. Einasto , E. Tago , A. A. Starobinsky , F. Atrio-Barandela , V. M"uller , A. Knebe , R. Cen
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