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High Redshift Metals I.: The Decline of C IV at z > 5.3
George D. Becker, Michael Rauch, Wallace L. W. Sargent
We present the results from our search for C IV in the intergalactic medium at redshifts z=5.3-6.0. We have observed four z~6 QSOs with Keck/NIRSPEC in echelle mode. The data are t…
A Population of Faint Extended Line Emitters and the Host Galaxies of Optically Thick QSO Absorption Systems
Michael Rauch, Martin Haehnelt, Andrew Bunker +10
We have conducted a long slit search for low surface brightness Lyman-alpha emitters at redshift 2.67 < z < 3.75. A 92 hour long exposure with VLT/FORS2 down to a 1-sigma surface b…
How cold is cold dark matter? Small scales constraints from the flux power spectrum of the high-redshift Lyman-alpha forest
M. Viel, G. D. Becker, J. S. Bolton +3
We present constraints on the mass of warm dark matter (WDM) particles derived from the Lyman-alpha flux power spectrum of 55 high- resolution HIRES spectra at 2.0 < z < 6.4. From…
The Evolution of Optical Depth in the Ly-alpha Forest: Evidence Against Reionization at z~6
George D. Becker, Michael Rauch, Wallace L. W. Sargent
We examine the evolution of the IGM Ly-alpha optical depth distribution using the transmitted flux probability distribution function (PDF) in a sample of 63 QSOs spanning absorptio…
Discovery of excess O I absorption towards the z = 6.42 QSO SDSS J1148+5251
George D. Becker, Wallace L. W. Sargent, Michael Rauch +1
We present a search for O I in the spectra of nine 4.9 < z_qso < 6.4 QSOs taken with Keck/HIRES. We detect six systems with N(O I) > 10^13.7 cm^{-2} in the redshift intervals where…
Expansion and Collapse in the Cosmic Web
Michael Rauch, George D. Becker, Matteo Viel +5
We study the kinematics of the gaseous cosmic web at high redshift with Lyman alpha forest absorption in multiple QSO sightlines. Using a simple analytic model and a cosmological h…
Observations of Chemically Enriched QSO Absorbers near z ~ 2.3 Galaxies: Galaxy-Formation Feedback Signatures in the IGM
Robert A. Simcoe, Wallace L. W. Sargent, Michael Rauch +1
We present a study of galaxies and intergalactic gas toward the z=2.73 quasar HS1700+6416, to explore the effects of galaxy formation feedback on the IGM. Our observations and ioni…
Large-Scale Correlations in the Lyman-alpha Forest at z = 3-4
George D. Becker, Wallace L. W. Sargent, Michael Rauch
We present a study of the spatial coherence of the intergalactic medium toward two pairs of high-redshift quasars with moderate angular separations observed with Keck/ESI, Q1422+23…
Supernova Remnants in the Fossil Starburst in M82
Richard de Grijs, Robert W. O'Connell, George D. Becker +2
We report the discovery of ten compact H-alpha-bright sources in the post-starburst region northeast of the center of M82, ``M82 B.'' These objects have H alpha luminosities and si…