English
Related papers

Related papers: QSO Absorption Line Systems

200 papers

A major limitation and a continuing source of confusion in the interpretation of molecular line observations has been the large degree of chemical complexity that is observed in star-forming molecular cores. The past decade has seen…

Astrophysics · Physics 2017-01-18 Edwin A. Bergin

The heavy elements near QSOs provide unique measures of the star formation and chemical evolution in young galactic nuclei or pre-galactic condensations. Studies of quasar abundances also naturally address a variety of questions regarding…

Astrophysics · Physics 2007-05-23 Fred Hamann

Quantitative spectroscopy is a powerful technique from which we can extract information about the physical properties and surface chemical composition of stars. In this chapter, I guide the reader through the main ideas required to get…

Solar and Stellar Astrophysics · Physics 2020-07-22 S. Simón-Díaz

Great strides have been made in the last two decades in determining how galaxies evolve from their initial dark matter seeds to the complex structures we observe at z=0. The role of mergers has been documented through both observations and…

These lectures review some of the techniques used to analyze the arrival direction distribution of Cosmic Rays, and some relevant results on the field.

High Energy Astrophysical Phenomena · Physics 2009-02-23 Silvia Mollerach

We discuss the different physical processes that are important to understand the thermal X-ray emission and absorption spectra of the diffuse gas in clusters of galaxies and the warm-hot intergalactic medium. The ionisation balance, line…

Astrophysics · Physics 2009-11-13 J. S. Kaastra , F. B. S. Paerels , F. Durret , S. Schindler , P. Richter

New millimeter wave observations of the molecular absorption line system in the gravitational lens to PKS1830-211 at z=0.88582 is presented. Self-calibrated interferometer data shows unequivocally that the previously detected absorption…

Astrophysics · Physics 2009-10-30 Tommy Wiklind , Francoise Combes

How is the universe organized on large scales? How did this structure evolve from the unknown initial conditions to the present time? The answers to these questions will shed light on the cosmology we live in, the amount, composition and…

Astrophysics · Physics 2009-09-25 Neta A. Bahcall

In this paper we present Monte-Carlo simulations of Lyman alpha absorption systems which originate in galactic haloes, galaxy discs and dark matter (DM) satellites around big central haloes. It is found that for strong Lyman alpha…

Astrophysics · Physics 2009-10-31 W. P. Lin , G. Boerner , H. J. Mo

Emission and absorption line observations of molecules in late-type stars are a vital component in our understanding of stellar evolution, dust formation and mass loss in these objects. The molecular composition of the gas in the…

Solar and Stellar Astrophysics · Physics 2016-08-24 T. J. Millar

We explore the multiphase structure of the circumgalactic medium (CGM) probed by synthetic spectra through a cosmological zoom-in galaxy formation simulation. We employ a Bayesian method for modelling a combination of absorption lines to…

Astrophysics of Galaxies · Physics 2018-07-11 Cameron Liang , Andrey Kravtsov , Oscar Agertz

We present the results of a search for metal absorption lines in the spectra of background QSOs whose sightlines pass close to foreground QSOs. We detect MgII(2796,2803) absorption in Sloan Digital Sky Survey (SDSS) spectra of four z>1.5…

Studies of galaxy clusters have proved crucial in helping to establish the standard model of cosmology, with a universe dominated by dark matter and dark energy. A theoretical basis that describes clusters as massive, multi-component,…

Cosmology and Nongalactic Astrophysics · Physics 2011-09-26 Steven W. Allen , August E. Evrard , Adam B. Mantz

As a byproduct of its search for the first star forming galaxies, NGST will obtain high-quality spectra for thousands of galaxies in the redshift range z = 0 - 6 and beyond. Most of the galaxies will possess strong emission-line spectra,…

Astrophysics · Physics 2007-05-23 R. C. Kennicutt

Intensity mapping has been attracting increasing interest as a way to study galaxy evolution and the large scale structure of the Universe. Instead of detecting individual galaxies, we measure the integrated emission from a volume of the…

Cosmology and Nongalactic Astrophysics · Physics 2019-11-13 José Fonseca

Studies of galaxy evolution at optical and near-infrared wavelengths have reached an interesting point in their historical development and the arrival of a new millenium provides an appropriate occasion to review the overall direction in…

Astrophysics · Physics 2009-11-06 Richard S Ellis

Observations of absorption systems in close, multiple lines of sight to gravitationally lensed QSOs can be used to infer the density fluctuations and motions of the gas clouds giving rise to the Lyman alpha forest phenomenon and to QSO…

Astrophysics · Physics 2007-05-23 Michael Rauch

Gamma-Ray Bursts represent unique tools to study the early phases of cosmic evolution, the formation of the first stars and galaxies. Absorption line spectra of these sources located in the Epoch of Reionization might provide us with key…

Instrumentation and Methods for Astrophysics · Physics 2018-02-07 A. Ferrara

We present the first results of an ALMA spectral survey of strong absorption lines for common interstellar species in the z=0.89 molecular absorber toward the lensed blazar PKS1830-211. The dataset brings essential information on the…

We used ultraviolet spectra from HST/STIS (R=30,000), together with optical spectra from Keck/HIRES (R=45,000), to study the three MgII-selected absorption systems at z=0.9254, 0.9276, and 0.9342 toward the quasar PG 1206+459. A multi-phase…

Astrophysics · Physics 2007-05-23 Jie Ding