Related papers: Exploring the Spectral Space of Low Redshift QSOs
To underscore the value of high spectral resolution for the study of low-z QSO absorption lines, we briefly present Space Telescope Imaging Spectrograph echelle data that demonstrate how increased resolution leads to dramatic improvement in…
We have observed nine QSOs with redshifts 0.85 to 4.16 at near-IR wavelengths with the adaptive optics bonnette of the Canada-France-Hawaii telescope. Exposure times ranged from 1500 to 24000s (mostly near 7000s) in J, H, or K bands, with…
We present the results of an infrared survey of QSO fields at z=0.95, 0.995 and 1.5. Each z<1 field was imaged to typical continuum limits of J=20.5, Kprime=19 (5 sigma), and line fluxes of 1.3E10{-16}ergs/cm^2/s (1 sigma)in a 1%…
We present a comprehensive analysis of a broad band spectral line survey of the Orion Kleinmann-Low nebula (Orion KL), one of the most chemically rich regions in the Galaxy, using the HIFI instrument on board the Herschel Space Observatory.…
Understanding how the physical properties of galaxies (e.g. their spectral type or age) evolve as a function of redshift relies on having an accurate representation of galaxy spectral energy distributions. While it has been known for some…
A model, called the linear transform network (LTN), is proposed to analyze the compression and estimation of correlated signals transmitted over directed acyclic graphs (DAGs). An LTN is a DAG network with multiple source and receiver…
The K20 survey is an ESO VLT optical and near-infrared spectroscopic survey aimed at obtaining spectral information and redshifts of a complete sample of about 550 objects to K_s\leq20.0 over two independent fields with a total area of 52…
We measure the large-scale real-space power spectrum P(k) using luminous red galaxies (LRGs) in the Sloan Digital Sky Survey (SDSS) and use this measurement to sharpen constraints on cosmological parameters from the Wilkinson Microwave…
We explore two methods of compressing the redshift space galaxy power spectrum and bispectrum with respect to a chosen set of cosmological parameters. Both methods involve reducing the dimension of the original data-vector ( e.g. 1000…
In the near future, the arrival of new surveys promises a significant increment in the number of quasars (QSO) at large redshift ranges. This will help to constrain the dark energy models using quasars. The Large Synoptic Survey Telescope…
Karhunen-Loeve expansions (KLE) of stochastic processes are important tools in mathematics, the sciences, economics, and engineering. However, the KLE is primarily useful for those processes for which we can identify the necessary…
Direct measurements of the masses of supermassive black holes (SMBHs) are key to understanding their growth and constrain their symbiotic relationship to their host galaxies. However, current methods used to directly measure black hole…
We investigated the properties of a sample of red Quasi-stellar Objects (QSOs) using optical, radio, and infrared data. These QSOs were selected from the Sloan Digital Sky Survey Data Release 7 (SDSS DR7) quasar catalog. We only selected…
Using a sample of 165 X-ray selected QSOs from seven deep ROSAT fields we investigate the X-ray spectral properties of an ``average''radio-quiet broad line QSO as a function of redshift. The QSO stacked spectra, in the observers 0.1-2 keV…
Despite decades of study, it remains unclear whether there are distinct radio-loud and radio-quiet populations of quasi-stellar objects (QSOs). Early studies were limited by inhomogeneous QSO samples, inadequate sensitivity to probe the…
The MOST, CoRoT, and Kepler space missions led to the discovery of a large number of intriguing, and in some cases unique, objects among which are pulsating stars, stars hosting exoplanets, binaries, etc. Although the space missions deliver…
Cosmological evolution of the QSO luminosity functions (LFs) at NIR/optical/X-ray bands for 1.3 < z < 3.5 is investigated based on the realistic QSO spectra. The accretion-disk theory predicts that although QSO luminosities only depend on…
For many complex materials systems, low-energy electron microscopy (LEEM) offers detailed insights into morphology and crystallography by naturally combining real-space and reciprocal-space information. Its unique strength, however, is that…
We present the first results of the Karhunen-Lo\`eve (KL) eigenmodes applied to real data of the Las Campanas Redshift Survey (LCRS) to simultaneously measure the values of the redshift-distortion parameter, $\beta = \Omega_0^{0.6}/b$, the…
A method for measuring the spectrum of a density field by a discrete wavelet space-scale decomposition (SSD) has been studied. We show how the power spectrum can effectively be described by the father function coefficients (FFC) of the…