English
Related papers

Related papers: Predicting QSO Continua in the Ly Alpha Forest

200 papers

The absorption system at $z=3.572$ towards Q1937--1009 provides the best extragalactic measurement of the atomic deuterium to hydrogen ratio, D/H. We have obtained a new low-resolution, high signal-to-noise ratio (SNR) Keck spectrum to…

Astrophysics · Physics 2009-10-30 Scott Burles , David Tytler

We use the redshift evolution of the lyman-alpha forest mean transmitted flux at z>2.5 to infer the evolution of the intensity of the ionizing background, using theoretical predictions for the density distribution of the intergalactic gas…

Astrophysics · Physics 2009-10-31 Patrick McDonald , Jordi Miralda-Escude

The Lyman-$\beta$ forest refers to a region in the spectra of distant quasars that lies between the rest-frame Lyman-$\beta$ and Lyman-$\gamma$ emissions. The forest in this region is dominated by a combination of absorption due to resonant…

A homogeneous sample of 99 moderate resolution QSO spectra at z > 1.7 were presented in Paper I, including 39 previously unpublished spectra from the Multiple Mirror Telescope. The statistics of the Lyman alpha forest were discussed. In…

Astrophysics · Physics 2009-10-31 J. Scott , J. Bechtold , A. Dobrzycki , V. Kulkarni

Recently, the Lyman-$\alpha$ (Ly$\alpha$) forest flux auto-correlation function has been shown to be sensitive to the mean free path of hydrogen-ionizing photons, $\lambda_{\text{mfp}}$, for simulations at $z \geq 5.4$. Measuring…

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

We present results from high resolution (R\simeq 28000) spectra of six high- redshift QSOs taken at the ESO NTT telescope that allow the detailed study of the Ly-alpha population in the redshift interval z=2.8-4.1. The typical Doppler…

Astrophysics · Physics 2009-10-28 E. Giallongo , S. Cristiani , S. D'Odorico , A. Fontana , S. Savaglio

When measuring the one-dimensional power spectrum of the Ly$\alpha$ forest, it is common to measure the power spectrum in flux fluctuations red-ward of the Ly$\alpha$ emission of quasars and subtract this power from the measurements of the…

Cosmology and Nongalactic Astrophysics · Physics 2014-05-13 Vid Iršič , Anže Slosar

We presents results of joint modeling of the probability distribution function (PDF) and the one-dimensional power spectrum (PS) of the Lya forest flux decrement. The sensitivity of these statistical measures to the shape and amplitude of…

Astrophysics · Physics 2009-11-10 Vincent Desjacques , Adi Nusser

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

We investigate the effect of non-Gaussianity on the reconstruction of the initial mass field from the Ly$\alpha$ forest. We show that the transmitted flux of QSO absorption spectra are highly non-Gaussian in terms of the statistics, the…

Astrophysics · Physics 2009-10-31 Long-Long Feng , Li-Zhi Fang

We present a measurement of the probability distribution function (PDF) of the transmitted flux in the Lya forest from a sample of 3492 quasars included in the SDSS DR3 data release. Our intention is to investigate the sensitivity of the…

Astrophysics · Physics 2008-11-26 Vincent Desjacques , Adi Nusser , Ravi K. Sheth

Techniques for the statistical analysis of the \Lya\ forest in high redshift quasars are developed, and applied to the low resolution (25 \AA) spectra of 29 of the 33 quasars in the Schneider-Schmidt-Gunn (SSG) sample.We find that the mean…

Astrophysics · Physics 2009-10-22 William H. Press , George B. Rybicki , Donald P. Schneider

We present new cosmological parameter constraints from the eBOSS Lyman-$\alpha$ forest survey. We use a new theoretical model and likelihood based on the PRIYA simulation suite. PRIYA is the first suite to resolve the Lyman-$\alpha$ forest…

Cosmology and Nongalactic Astrophysics · Physics 2024-07-19 M. A. Fernandez , Simeon Bird , Ming-Feng Ho

We forecast the sensitivity of future correlations between CMB lensing and the Lyman-$\alpha$ forest power spectrum. This squeezed-limit bispectrum probes the connection between the Lyman-$\alpha$ transmission and the underlying large-scale…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-06 Adrien La Posta , Emmanuel Schaan

We present a new catalogue of Damped Lyman-$\alpha$ absorbers from SDSS DR16Q, as well as new estimates of their statistical properties. Our estimates are computed with the Gaussian process models presented in Garnett et al. (2017); Ho et…

Astrophysics of Galaxies · Physics 2021-08-24 Ming-Feng Ho , Simeon Bird , Roman Garnett

The two-point correlation function, $\xi$, of Lyman-alpha forest is found to be large, $\xi = 1.8^{+1.6}_{-1.2}$, > 90% confidence level, on the scale of 250-500 km/s for a sample of absorbers (0 < z < 1.3) assembled from HST Key Project…

Astrophysics · Physics 2009-10-28 Andrew Ulmer

We have studied the possibility of measuring the cross-correlation of the redshifted HI 21-cm signal and the Lyman-$\alpha$ forest using an upcoming radio-interferometric array OWFA and an spectroscopic observation like SDSS-IV. Our results…

Cosmology and Nongalactic Astrophysics · Physics 2018-06-06 Anjan Kumar Sarkar , Somnath Bharadwaj , Tapomoy Guha Sarkar

We analyze the power spectrum of a QSO's Ly_alpha transmitted flux in the discrete wavelet transform (DWT) representation. Although the mean DWT power spectrum is consistent with its counterpart in Fourier representation, the spatial…

Astrophysics · Physics 2009-11-06 Hu Zhan , Priya Jamkhedkar , Li-Zhi Fang
‹ Prev 1 8 9 10 Next ›