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Modelling feedback from stars and black holes in galaxy mergers
We describe techniques for incorporating feedback from star formation and black hole (BH) accretion into simulations of isolated and merging galaxies. At present, the details of these processesExpand
Energy input from quasars regulates the growth and activity of black holes and their host galaxies
Simulations that simultaneously follow star formation and the growth of black holes during galaxy–galaxy collisions find that, in addition to generating a burst of star formation, a merger leads to strong inflows that feed gas to the supermassive black hole and thereby power the quasar. Expand
Cosmological smoothed particle hydrodynamics simulations: the entropy equation
We discuss differences in simulation results that arise between the use of either the thermal energy or the entropy as an independent variable in smoothed particle hydrodynamics (SPH). In thisExpand
Properties of galaxies reproduced by a hydrodynamic simulation
A simulation that starts 12 million years after the Big Bang, and traces 13 billion years of cosmic evolution with 12 billion resolution elements in a cube of 106.5 megaparsecs a side yields a reasonable population of ellipticals and spirals, reproduces the observed distribution of galaxies in clusters and characteristics of hydrogen on large scales, and at the same time matches the ‘metal’ and hydrogen content of galaxies on small scales. Expand
A Cosmological Framework for the Co-Evolution of Quasars, Supermassive Black Holes, and Elliptical Galaxies. I. Galaxy Mergers and Quasar Activity
We develop a model for the cosmological role of mergers in the evolution of starbursts, quasars, and spheroidal galaxies. By combining theoretically well-constrained halo and subhalo mass functionsExpand
Evolution of the Intergalactic Opacity: Implications for the Ionizing Background, Cosmic Star Formation, and Quasar Activity
We investigate the implications of the intergalactic opacity for the evolution of the cosmic UV luminosity density and its sources. Our main constraint is our measurement of the Ly? forest opacity atExpand
Baryons in the warm-hot intergalactic medium
Approximately 30%-40% of all baryons in the present-day universe reside in a warm-hot intergalactic medium (WHIM), with temperatures in the range 105 < T < 107 K. This is a generic prediction fromExpand
A Unified, Merger-driven Model of the Origin of Starbursts, Quasars, the Cosmic X-Ray Background, Supermassive Black Holes, and Galaxy Spheroids
We present an evolutionary model for starbursts, quasars, and spheroidal galaxies in which mergers between gas-rich galaxies drive nuclear inflows of gas, producing starbursts and feeding the buriedExpand
A New Calculation of the Ionizing Background Spectrum and the Effects of He II Reionization
The ionizing background determines the ionization balance and the thermodynamics of the cosmic gas. It is therefore a fundamental ingredient to theoretical and empirical studies of both theExpand
A Direct Precision Measurement of the Intergalactic Lyα Opacity at 2 ≤ z ≤ 4.2* **
We measure the evolution of the intergalactic Lyα effective optical depth, -->τeff, over the redshift range -->2 ≤ z≤ 4.2 from a sample of 86 high-resolution, high-S/N quasar spectra obtained withExpand