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Singular manifolds, topology change and the dynamics of compactification (2007)
Journal Article
Butcher, N. A., & Saffin, P. M. (2007). Singular manifolds, topology change and the dynamics of compactification. Journal of High Energy Physics, 2007(11), https://doi.org/10.1088/1126-6708/2007/11/062

We investigate the dynamics of the geometric transitions associated to compactified spacetimes. By including the dynamics of gravity we are able to follow the evolution of collapsing cycles as they attempt to undergo a topology changing transition. R... Read More about Singular manifolds, topology change and the dynamics of compactification.

A closer look at using quasar near-zones as a probe of neutral hydrogen in the intergalactic medium (2007)
Journal Article
S. Bolton, J., & G. Haehnelt, M. (2007). A closer look at using quasar near-zones as a probe of neutral hydrogen in the intergalactic medium. Monthly Notices of the Royal Astronomical Society: Letters, 381(1), L35-L39. https://doi.org/10.1111/j.1745-3933.2007.00361.x

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 hydrogen content of the intergalactic medium (IGM) a... Read More about A closer look at using quasar near-zones as a probe of neutral hydrogen in the intergalactic medium.

The observed ionization rate of the intergalactic medium and the ionizing emissivity at z >5: Evidence for a photon starved and extended epoch of reionization (2007)
Journal Article
S. Bolton, J., & G. Haehnelt, M. (2007). The observed ionization rate of the intergalactic medium and the ionizing emissivity at z >5: Evidence for a photon starved and extended epoch of reionization. Monthly Notices of the Royal Astronomical Society, 382(1), 325–341. https://doi.org/10.1111/j.1365-2966.2007.12372.x

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 per hydrogen atom at z=5 and 6. We find the photoion... Read More about The observed ionization rate of the intergalactic medium and the ionizing emissivity at z >5: Evidence for a photon starved and extended epoch of reionization.

Controlling Pattern Formation in Nanoparticle Assemblies via Directed Solvent Dewetting (2007)
Journal Article
Martin, C., Blunt, M., Pauliac-Vaujour, E., Stannard, A., Moriarty, P., Vancea, I., & Thiele, U. (2007). Controlling Pattern Formation in Nanoparticle Assemblies via Directed Solvent Dewetting. Physical Review Letters, 99,

We have achieved highly localised control of pattern formation in two dimensional nanoparticle assemblies by direct modification of solvent dewetting dynamics. A striking dependence of nanoparticle organisation on the size of atomic force microscope-... Read More about Controlling Pattern Formation in Nanoparticle Assemblies via Directed Solvent Dewetting.

Particle transfer in braneworld collisions (2007)
Journal Article
Saffin, P. M., & Tranberg, A. (2007). Particle transfer in braneworld collisions. Journal of High Energy Physics, 2007(8), https://doi.org/10.1088/1126-6708/2007/08/072

We study the behaviour of fermions localized on moving kinks as these collide with either antikinks or spacetime boundaries. We numerically solve for the evolution of the scalar kinks and the bound (i.e. localized) fermion modes, and calculate the nu... Read More about Particle transfer in braneworld collisions.

Coerced Mechanical Coarsening of Nanoparticle Assemblies (2007)
Journal Article
Blunt, M., Martin, C., Ahola-Tuomi, M., Pauliac-Vaujour, E., Sharp, P., Nativo, P., …Nativo, P. (2007). Coerced Mechanical Coarsening of Nanoparticle Assemblies. Nature Nanotechnology, 2, https://doi.org/10.1038/nnano.2007.25

Coarsening is a ubiquitous phenomenon [1-3] that underpins countless processes in nature, including epitaxial growth [1,3,4], the phase separation of alloys, polymers and binary fluids [2], the growth of bubbles in foams5, and pattern formation in bi... Read More about Coerced Mechanical Coarsening of Nanoparticle Assemblies.

Oscillons and quasi-breathers in D+1 dimensions (2007)
Journal Article
Saffin, P. M., & Tranberg, A. (2007). Oscillons and quasi-breathers in D+1 dimensions. Journal of High Energy Physics, 2007(1), https://doi.org/10.1088/1126-6708/2007/01/030

We study oscillons in D+1 space-time dimensions using a spherically symmetric ansatz. From Gaussian initial conditions, these evolve by emitting radiation, approaching ``quasi-breathers'', near-periodic solutions to the equations of motion. Using a t... Read More about Oscillons and quasi-breathers in D+1 dimensions.

The nature and evolution of the highly ionized near-zones in the absorption spectra of z~6 quasars (2006)
Journal Article
S. Bolton, J., & G. Haehnelt, M. (2007). The nature and evolution of the highly ionized near-zones in the absorption spectra of z~6 quasars. Monthly Notices of the Royal Astronomical Society, 374(2), 493–514. https://doi.org/10.1111/j.1365-2966.2006.11176.x

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 as near-zones, can constrain the ionization state... Read More about The nature and evolution of the highly ionized near-zones in the absorption spectra of z~6 quasars.

Scaling in a SU(2)/Z_3 model of cosmic superstring networks (2006)
Journal Article
Hindmarsh, M., & Saffin, P. (2006). Scaling in a SU(2)/Z_3 model of cosmic superstring networks. Journal of High Energy Physics, 2006(8), https://doi.org/10.1088/1126-6708/2006/08/066

Motivated by recent developments in superstring theory in the cosmological context, we examine a field theory which contains string networks with 3-way junctions. We perform numerical simulations of this model, identify the length scales of the netwo... Read More about Scaling in a SU(2)/Z_3 model of cosmic superstring networks.