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High-redshift gamma-ray bursts (GRBs) offer an extraordinary opportunity to study aspects of the early universe, including the cosmic star formation rate (SFR). Motivated by the two recent highest-zExpand
The accretion history of dark matter haloes - III. A physical model for the concentration-mass relation
We present a semi-analytic, physically motivated model for dark matter halo concentration as a function of halo mass and redshift. The semi-analytic model is intimately based on hierarchicalExpand
The Murchison Widefield Array: The Square Kilometre Array Precursor at Low Radio Frequencies
Abstract The Murchison Widefield Array (MWA) is one of three Square Kilometre Array Precursor telescopes and is located at the Murchison Radio-astronomy Observatory in the Murchison Shire of theExpand
A large neutral fraction of cosmic hydrogen a billion years after the Big Bang
It is shown that the IGM surrounding these quasars had a neutral hydrogen fraction of tens of per cent before the quasar activity started, much higher than the previous lower limits of ∼0.1 per cent, suggesting the presence of a second peak in the mean ionization history of the Universe. Expand
Low-Frequency Gravitational Waves from Massive Black Hole Binaries: Predictions for LISA and Pulsar Timing Arrays
The coalescence of massive black hole (BH) binaries due to galaxy mergers provides a primary source of low-frequency gravitational radiation detectable by pulsar timing measurements and by theExpand
Improved measurements of the intergalactic medium temperature around quasars: possible evidence for the initial stages of He II reionization at z ≃ 6
We present measurements of the intergalactic medium (IGM) temperature within ∼5 proper Mpc of seven luminous quasars at z ≃ 6. The constraints are obtained from the Doppler widths of Lyα absorptionExpand
Reionization and Cosmology with 21-cm Fluctuations
Measurement of the spatial distribution of neutral hydrogen via the redshifted 21-cm line promises to revolutionize our knowledge of the epoch of reionization and the first galaxies, and may provideExpand
Near-infrared observations of Type Ia supernovae: the best known standard candle for cosmology
We present an analysis of the Hubble diagram for 12 normal Type Ia supernovae (SNe Ia) observed in the near-infrared (NIR) J and H bands. We select SNe exclusively from the redshift range 0.03 < z <Expand
Measurement of Galaxy Clustering at z~7.2 and the Evolution of Galaxy Bias from 3.8
Lyman-Break Galaxy (LBG) samples observed during reionization ($z\gtrsim6$) with Hubble Space Telescope's Wide Field Camera 3 are reaching sizes sufficient to characterize their clusteringExpand
The accretion history of dark matter haloes – II. The connections with the mass power spectrum and the density profile
We explore the relation between the structure and mass accretion histories of dark matter halos using a suite of cosmological simulations. We confirm that the formation time, defined as the time whenExpand