Resolving the high redshift Lyman-alpha forest in smoothed particle hydrodynamics simulations (2009)
Bolton, James S., Becker, George D.
We use a large set of cosmological smoothed particle hydrodynamics (SPH) simulations to examine the effect of mass resolution and box size on synthetic Lya forest spectra at 2 \leq z \leq 5. The mass...
The evolution of the Lyman-alpha forest effective optical depth following HeII reionisation (2009)
Bolton, James S., Oh, S. Peng, Furlanetto, Steven R.
Three independent observational studies have now detected a narrow (\Delta z ~ 0.5) dip centred at z=3.2 in the otherwise smooth redshift evolution of the Lya forest effective optical depth. This...
Photo-heating and the fate of hard photons during the reionisation of HeII by quasars (2008)
Bolton, James S., Oh, S. Peng, Furlanetto, Steven R.
We use a combination of analytic and numerical arguments to consider the impact of quasar photo-heating during HeII reionisation on the thermal evolution of the intergalactic medium (IGM). We...
Viel, Matteo, Becker, George D., Bolton, James S., Haehnelt, Martin G., Rauch, Michael, Sargent, Wallace L.
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 2.0~5.6 keV (2sigma) for sterile...
Viel, Matteo, Becker, George D., Bolton, James S., Haehnelt, Martin G., Rauch, Michael, Sargent, Wallace L. W.
Bolton, James S., Haehnelt, Martin G.
We examine a large set of synthetic quasar spectra to realistically assess the potential of using the relative sizes of highly ionized near-zones in the Lya and Lyb forest as a probe of the neutral...
Bolton, James S., Haehnelt, Martin G.
We use a large set of hydrodynamical simulations, combined with measurements of the Lyman alpha opacity of the IGM taken from the literature, to obtain robust estimates for the photoionization rate...
Bolton, James S., Haehnelt, Martin G.
We use state-of-the-art hydrodynamical simulations combined with a 1D radiative transfer code to assess the extent to which the highly ionized regions observed close to z~6 quasars, which we refer to...
Spatial fluctuations in the spectral shape of the UV background at 2 (2005)
Bolton, James S., Haehnelt, Martin G., Viel, Matteo, Carswell, Robert F.
The low density hydrogen and helium in the IGM probed by QSO absorption lines is sensitive to the amplitude and spectral shape of the metagalactic UV background. We use realistic HI and HeII Ly-alpha...
Constraints on the metagalactic hydrogen ionization rate from the Lyman-alpha forest opacity (2005)
Bolton, James S., Haehnelt, Martin G., Viel, Matteo, Springel, Volker
Understanding the sources responsible for reionizing the Universe is a key goal of observational cosmology. A discrepancy has existed between the metagalactic hydrogen ionization rate, Gamma_HI,...
The Lyman alpha forest opacity and the metagalactic hydrogen ionization rate at z~ 2-4 (2005)
Bolton, James S., Haehnelt, Martin G., Viel, Matteo, Springel, Volker
Constraints on the meta-galactic hydrogen ionisation rate from the Lyman-α forest opacity (2005)
Bolton, James S., Haehnelt, Martin G., Viel, Matteo, Springel, Volker
The Lyman-alpha forest opacity and the metagalactic hydrogen ionization rate at z~2-4 (2004)
Bolton, James S., Haehnelt, Martin G., Viel, Matteo, Springel, Volker
Estimates of the metagalactic hydrogen ionization rate from the Lyman-alpha forest opacity in QSO absorption spectra depend on the complex density distribution of neutral hydrogen along the...