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Colliding branes and big crunches (2011)
Journal Article
Omotani, J., Saffin, P. M., & Louko, J. (2011). Colliding branes and big crunches. Physical Review D, 84(6), Article 063526. https://doi.org/10.1103/PhysRevD.84.063526

We examine the global structure of colliding domain walls in AdS spacetime and come to the conclusion that singularities forming from such collisions are of the big-crunch type rather than that of a black brane.

How neutral is the intergalactic medium surrounding the redshift z=7.085 quasar ULAS J1120+0641? (2011)
Journal Article
S. Bolton, J., G. Haehnelt, M., J. Warren, S., C. Hewett, P., J. Mortlock, D., P. Venemans, B., G. McMahon, R., & Simpson, C. (2011). How neutral is the intergalactic medium surrounding the redshift z=7.085 quasar ULAS J1120+0641?. Monthly Notices of the Royal Astronomical Society: Letters, 416(1), L70–L74. https://doi.org/10.1111/j.1745-3933.2011.01100.x

The quasar ULAS J1120+0641 at redshift z=7.085 has a highly ionised near zone which is smaller than those around quasars of similar luminosity at z~6. The spectrum also exhibits evidence for a damping wing extending redward of the systemic Lya redshi... Read More about How neutral is the intergalactic medium surrounding the redshift z=7.085 quasar ULAS J1120+0641?.

Real-time fermions for baryogenesis simulations (2011)
Journal Article
Saffin, P. M., & Tranberg, A. (2011). Real-time fermions for baryogenesis simulations. Journal of High Energy Physics, 2011(7), https://doi.org/10.1007/JHEP07%282011%29066

We study how to numerically simulate quantum fermions out of thermal equilibrium, in the context of electroweak baryogenesis. We find that by combining the lattice implementation of Aarts and Smit [1] with the "low cost" fermions of Borsanyi and Hind... Read More about Real-time fermions for baryogenesis simulations.

The impact of spatial fluctuations in the ultra-violet background on intergalactic carbon and silicon (2011)
Journal Article
S. Bolton, J., & Viel, M. (2011). The impact of spatial fluctuations in the ultra-violet background on intergalactic carbon and silicon. Monthly Notices of the Royal Astronomical Society, 414(1), 241–252. https://doi.org/10.1111/j.1365-2966.2011.18384.x

Spatial inhomogeneities in the spectral shape of the ultra-violet background (UVB) at the tail-end of HeII reionisation are thought to be the primary cause of the large fluctuations observed in the HeII to HI Ly-a forest optical depth ratio, tau_HeII... Read More about The impact of spatial fluctuations in the ultra-violet background on intergalactic carbon and silicon.

Measurements of the ultraviolet background at 4.6 < z < 6.4 using the quasar proximity effect (2011)
Journal Article
(2011). Measurements of the ultraviolet background at 4.6 < z < 6.4 using the quasar proximity effect. Monthly Notices of the Royal Astronomical Society, 412(4), 2543-2562. https://doi.org/10.1111/j.1365-2966.2010.18072.x

We present measurements of the ionizing ultraviolet background (UVB) at z∼ 5–6 using the quasar proximity effect. The 15 quasars in our sample cover the range 4.6 < zq < 6.4, enabling the first proximity-effect measurements of the UVB at z > 5. The m... Read More about Measurements of the ultraviolet background at 4.6 < z < 6.4 using the quasar proximity effect.

Multi-Galileons, solitons, and Derrick’s theorem (2011)
Journal Article
Padilla, A., Saffin, P. M., & Zhou, S.-Y. (2011). Multi-Galileons, solitons, and Derrick’s theorem. Physical Review D, 83(4), https://doi.org/10.1103/PhysRevD.83.045009

The field theory Galilean symmetry, which was introduced in the context of modified gravity, gives a neat way to construct Lorentz-covariant theories of a scalar field, such that the equations of motion contain at most second-order derivatives. Here... Read More about Multi-Galileons, solitons, and Derrick’s theorem.

Bi-galileon theory II: phenomenology (2011)
Journal Article
Padilla, A., Saffin, P. M., & Zhou, S.-Y. (2011). Bi-galileon theory II: phenomenology. Journal of High Energy Physics, 2011(1), https://doi.org/10.1007/JHEP01%282011%29099

We continue to introduce bi-galileon theory, the generalisation of the single galileon model introduced by Nicolis et al. The theory contains two coupled scalar fields and is described by a Lagrangian that is invariant under Galilean shifts in those... Read More about Bi-galileon theory II: phenomenology.

Reducing the gradient artefact in simultaneous EEG-fMRI by adjusting the subject’s axial position (2011)
Journal Article
Mullinger, K. J., Yan, W. X., & Bowtell, R. W. (2011). Reducing the gradient artefact in simultaneous EEG-fMRI by adjusting the subject’s axial position. NeuroImage, 54(3), https://doi.org/10.1016/j.neuroimage.2010.09.079

Large artefacts which compromise EEG data quality are generated when electroencephalography (EEG) and functional magnetic resonance imaging (fMRI) are carried out concurrently. The gradient artefact produced by the time-varying magnetic field gradien... Read More about Reducing the gradient artefact in simultaneous EEG-fMRI by adjusting the subject’s axial position.