Related papers: Spectral Analysis of the Lyman-Alpha Forest Using …
This article consists of a brief discussion of the energy density over time or frequency that is obtained with the wavelet transform. Also an efficient algorithm is suggested to calculate the continuous transform with the Morlet wavelet.…
We describe the properties of the Ly$\alpha$ forest in the column density range $\nhi \geq 2\times10^{12}$ cm$^{-2}$ based on 1056 lines in the wavelength range 4300--5100\AA measured in extremely high S/N, $R=36,000$ spectra of four…
New experimental techniques based on non-linear ultrafast spectroscopies have been developed over the last few years, and have been demonstrated to provide powerful probes of quantum dynamics in different types of molecular aggregates,…
This paper introduces a Deep Scattering network that utilizes Dual-Tree complex wavelets to extract translation invariant representations from an input signal. The computationally efficient Dual-Tree wavelets decompose the input signal into…
We examine the possible effects of UV background fluctuations on the pixel flux power spectrum and auto-correlation function of the LyA forest due to a finite number of sources in an attenuating medium. We consider scenarios in which QSO…
The Lyman-alpha forest is a unique probe of large-scale matter density fluctuations at high redshift z > 2. We measure the one-dimensional Lyman-alpha forest power spectrum using the first data provided by the Dark Energy Spectroscopic…
Lyman alpha absorber correlations contain information about the underlying density distribution associated with a particular class of absorbers. As such, they provide an opportunity to independently measure the "bias" of the Lyman alpha…
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…
Wavelet Transforms are a widely used technique for decomposing a signal into coefficient vectors that correspond to distinct frequency/scale bands while retaining time localization. This property enables an adaptive analysis of signals at…
We explore several physical effects on the power spectrum of the Lyman-alpha forest transmitted flux. The effects we investigate here are usually not part of hydrodynamic simulations and so need to be estimated separately. The most…
We present a semi-analytic model for the Lyman-$\alpha$ forest that is inspired by the Halo Model. This model is built on the absorption line decomposition of the forest. Flux correlations are decomposed into those within each absorption…
We have measured the transmission of the Lyman alpha forest produced by neutral hydrogen scattering in the intergalactic medium between redshifts 2 and 6.3 using high signal to noise, high resolution (R > 5000) observations of 50 quasars…
Statistical properties of gas absorption in high redshift quasars such as power spectrum and bispectrum allow one to determine the evolution of structure over the redshift range 2<z<4. Sloan Digital Sky Survey (SDSS) will measure around…
We present the BOSS Lyman-alpha (Lya) Forest Sample from SDSS Data Release 9, comprising 54,468 quasar spectra with zqso > 2.15 suitable for Lya forest analysis. This data set probes the intergalactic medium with absorption redshifts 2.0 <…
Spectra of the QSO pair Q0307-195A,B have been obtained in the Ly-alpha Forest (3660 - 3930 A) and C IV (4720 - 4850 A) regions with a FWHM resolution between 0.7 and 0.5 A. 46 lines have been detected in the spectrum of object A while 36…
A sample of eight quasars observed at high resolution and signal-to-noise is used to determine the probability distribution function (PDF), the power spectrum, and the correlation function of the transmitted flux in the \lya forest, in…
Higher order clustering statistics of Ly$\alpha$ forest provide a unique probe to study non-gaussianity in Intergalactic matter distribution up to high redshifts and from large to small scales. The author presents a brief review of his work…
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…
(abridged) The flux power spectrum of the Lyman-alpha forest in quasar (QSO) absorption spectra is sensitive to a wide range of cosmological and astrophysical parameters and instrumental effects. Modelling the flux power spectrum in this…
We demonstrate how the image analysis technique of wavelet decomposition can be applied to the gamma-ray sky to separate emission on different angular scales. New structures on scales that differ from the scales of the conventional…