The nature of HI absorbers in GRB afterglows: clues from hydrodynamic simulations (2009)
Pontzen, Andrew, Deason, Alis, Governato, Fabio, Pettini, Max, Wadsley, James, Quinn, Thomas, ...
In recent work, we have shown that it is possible to link quantitatively many aspects of damped Lyman alpha (DLA) absorbers in the spectra of quasars to high resolution simulations of galaxy...
Rogues' gallery: the full freedom of the Bianchi CMB anomalies (2009)
Combining a recent derivation of the CMB evolution equations for homogeneous but anisotropic (Bianchi) cosmologies with an account of the full linearized dynamical freedoms available in such models,...
Dust Biasing of Damped Lyman Alpha Systems: a Bayesian Analysis (2008)
If damped Lyman alpha systems (DLAs) contain even modest amounts of dust, the ultraviolet luminosity of the background quasar can be severely diminished. When the spectrum is redshifted, this leads...
Damped Lyman Alpha Systems in Galaxy Formation Simulations (2008)
Pontzen, Andrew, Governato, Fabio, Pettini, Max, Booth, C. M., Stinson, Greg, Wadsley, James, ...
We investigate the population of z=3 damped Lyman alpha absorbers (DLAs) in a recent series of high resolution galaxy formation simulations. The simulations are of interest because they form at z=0...
Direct Observational Test Rules Out Small MgII Absorbers (2007)
Pontzen, Andrew, Hewett, Paul, Carswell, Robert, Wild, Vivienne
Recent observations suggest the incidence of strong intervening MgII absorption systems along the line-of-sight to gamma ray burst (GRB) afterglows is significantly higher than expected from...
Bianchi Model CMB Polarization and its Implications for CMB Anomalies (2007)
Pontzen, Andrew, Challinor, Anthony
We derive the CMB radiative transfer equation in the form of a multipole hierarchy in the nearly-Friedmann-Robertson-Walker limit of homogeneous, but anisotropic, universes classified via their...
Is the Concentration of Dark Matter Halos at Virialization Universal ? (2007)
Ricotti, Massimo, Pontzen, Andrew, Viel, Matteo
Several recent studies suggest a correlation between dark matter halo mass and the shape of the density profile. We re-analyze simulations from Ricotti (2003) in which such a correlation was...