Results 21 to 30 of about 5,191,368 (191)

Constraining Variable High Velocity Winds from Broad Absorption Line Quasars with Multi-Epoch Spectroscopy

, 2012
2 pages, 2 figures, Conference proceedings for "AGN Winds in Charleston," Charleston, SC, Oct 15-18, 2011.
Haggard, Daryl, Arraki, Kenza S., Green, Paul J., Aldcroft, Tom, Anderson, Scott F.   +4 more
openaire   +2 more sources

Keck HIRES Spectroscopy of the FeiiLow‐Ionization Broad Absorption Line Quasar FBQS 0840+3633: Evidence for Two Outflows on Different Scales

The Astrophysical Journal, 2002
A Keck echelle spectrum of the quasar FBQS 0840+3633 reveals outflowing gas that gives rise to blueshifted absorption lines of many low-ionization species. The gas covers a range of velocities from -700 to -3500 km s-1, with two main components centered at -900 and -2800 km s-1.
Martijn de Kool, Robert H. Becker, Nahum Arav, Michael D. Gregg, Richard L. White   +4 more
openaire   +1 more source

Reionization and high-redshift galaxies: the view from quasar absorption lines [PDF]

, 2015
Determining when and how the first galaxies reionised the intergalactic medium promises to shed light on both the nature of the first objects and the cosmic history of baryons.
Bolton, James S., Lidz, Adam, Becker, George D.   +2 more
core   +1 more source

Simultaneous Existence of the Line-locking and Velocity Shift Signatures in Quasar SDSS J004613.54+010425.7

The Astrophysical Journal
This study presents a detailed investigation of the broad absorption line (BAL) systems in the quasar SDSS J004613.54+010425.7 (hereafter J0046+0104), which makes characters of the simultaneous existence of line-locking and velocity shift signatures ...
Wei-Jian Lu, Ying-Ru Lin
doaj   +1 more source

Feasibility Study for Application of Digitized Henize Mt. Wilson Michigan Southern Sky Hα$$ \boldsymbol{\alpha} $$ Survey Low‐Dispersive Spectral Plates for Searches for Anomalous and Highly Redshifted Objects

Astronomische Nachrichten, Volume 347, Issue 6, July 2026.
ABSTRACT The goal of this study is to confirm the feasibility of the use of digitized low dispersive MtWilson Michigan Southern Sky Hα$$ \alpha $$ survey astronomical photographic plates for modern astrophysical research. The detection of highly redshifted objects, such as early galaxies and quasars, is fundamental to understanding the universe's ...
Tauseef Ahmad Zafar, René Hudec, Marta Mara Merono Vidagany, Fehmi Mejri   +3 more
wiley   +1 more source

The relationship between Gas and Galaxies [PDF]

, 2009
We have investigated the 2D 2-point correlation function, ƐAG, between low column density Lya absorbers and galaxies at a redshift z ~ 1 for the first time.
Shone, Allen Maurice
core  

Coordinated Velocity Shift of Multiple C iv and Si iv Broad Absorption Lines in Quasar SDSS J113048.45+225206.6

The Astrophysical Journal
We present an analysis of the coordinated velocity shifts observed in multiple C iv and Si iv broad absorption lines (BALs) in the quasar SDSS J113048.45+225206.6.
Wei-Jian Lu, Ying-Ru Lin
doaj   +1 more source

A SPectroscopic Survey of Biased Halos in the Reionization Era (ASPIRE): JWST Discovers an Overdensity around a Metal Absorption-selected Galaxy at z ∼ 5.5

The Astrophysical Journal Letters, 2023
The launch of JWST opens a new window for studying the connection between metal-line absorbers and galaxies at the end of the Epoch of Reionization.
Yunjing Wu, Feige Wang, Zheng Cai, Xiaohui Fan, Kristian Finlator, Jinyi Yang, Joseph F. Hennawi, Fengwu Sun, Jaclyn B. Champagne, Xiaojing Lin, Zihao Li, Zuyi Chen, Eduardo Bañados, George D. Becker, Sarah E. I. Bosman, Gustavo Bruzual, Stephane Charlot, Hsiao-Wen Chen, Jacopo Chevallard, Anna-Christina Eilers, Emanuele Paolo Farina, Xiangyu Jin, Hyunsung D. Jun, Koki Kakiichi, Mingyu Li, Weizhe Liu, Maria A. Pudoka, Wei Leong Tee, Zhang-Liang Xie, Siwei Zou   +29 more
doaj   +1 more source

Hidden No More: Spotlight on Tidal Disruption Events in Active Galactic Nuclei

Astronomische Nachrichten, Volume 347, Issue 5, June 2026.
ABSTRACT Tidal disruption events (TDEs) are typically discovered in previously quiescent galaxies. However, earlier studies have revealed a handful of TDEs occurring in pre‐existing active galactic nuclei (AGN). We discuss AT2019aalc, a promising TDE candidate in an AGN, and compare it to similar sources.
Patrik Milán Veres
wiley   +1 more source

Acceleration of C iv and Si iv Broad Absorption Lines in Quasar SDSS J140058.79+260619.4

The Astronomical Journal
We report the discovery of a velocity shift signature in the C iv and Si iv broad absorption lines (BALs) of the quasar SDSS J140058.79+260619.4 ( z _em  = 2.351). From its two-epoch spectra, we find two BAL systems (systems A and B) in C iv and/or Si iv
Ying-Ru Lin, Wei-Jian Lu
doaj   +1 more source