Double-Chooz: a search for Theta13

The Double-Chooz experiment goal is to search for a non-vanishing value of the Theta13 neutrino mixing angle. This is the last step to accomplish prior moving towards a new era of precision measurements in the lepton sector. The current best constraint on the third mixing angle comes from the CHOOZ reactor neutrino experiment $\sin(2\theta_{13})^{2}<0.2$ (90% C.L., $\Delta m_{atm}^{2}=2.0$ eV$^{2}$). Double-Chooz will explore the range of $\sin(2\theta_{13})^{2}$ from 0.2 to 0.03-0.02, within three years of data taking. The improvement of the CHOOZ result requires an increase in the statistics, a reduction of the systematic error below one percent, and a careful control of the backgrounds. Therefore, Double-Chooz will use two identical detectors, one at 150 m and another at 1.05 km distance from the Chooz nuclear cores. In addition, we will to use the near detector as a ``state of the art'' prototype to investigate the potential of neutrinos for monitoring the civil nuclear power plants. The plan is to start operation with two detectors in 2008, and to reach a sensitivity sin$^{2}$$(2\theta_{13})$ of 0.05 in 2009, and 0.03-0.02 in 2011.Comment: 3 pages, 1 figure, Proceedings of Nufact'04, July 26 - August 01 2004, Osak

Thermodynamics of itinerant metamagnetic transitions

Theoretical studies of the metamagnetism and anomalous phase of Sr3Ru2O7 have focused on the role of van Hove singularities, although much experimental evidence points towards quantum criticality having a large effect. We investigate the magnetic and thermodynamic properties of systems where magnetic field tunes through such a peak in the electronic density of states. We study the generic case of a van Hove singularity in 2D. We see that in combination with the requirement of number conservation and interaction effects the peak in the density of states produces several interesting phenomena including raising the critical field of the transition above naive estimates, altering the relationship between temperature and field scales and creating a distinctive double-peak structure in the electronic specific heat. We show that this apparent non-Fermi liquid behaviour can be caused at mean-field level by a peak in the density of states.Comment: 6 pages, 4 figure

Public Health in the 1980s and 1990s: Decline and rise?

Annotated and edited transcript of a Witness Seminar held on 12 October 2004. Introduction by Professor Virginia Berridge, London School of Hygiene and Tropical Medicine.First published by the Wellcome Trust Centre for the History of Medicine at UCL, 2006.©The Trustee of the Wellcome Trust, London, 2006.All volumes are freely available online at: www.history.qmul.ac.uk/research/modbiomed/wellcome_witnesses/Annotated and edited transcript of a Witness Seminar held on 12 October 2004. Introduction by Professor Virginia Berridge, London School of Hygiene and Tropical Medicine.Annotated and edited transcript of a Witness Seminar held on 12 October 2004. Introduction by Professor Virginia Berridge, London School of Hygiene and Tropical Medicine.Annotated and edited transcript of a Witness Seminar held on 12 October 2004. Introduction by Professor Virginia Berridge, London School of Hygiene and Tropical Medicine.Annotated and edited transcript of a Witness Seminar held on 12 October 2004. Introduction by Professor Virginia Berridge, London School of Hygiene and Tropical Medicine.Annotated and edited transcript of a Witness Seminar held on 12 October 2004. Introduction by Professor Virginia Berridge, London School of Hygiene and Tropical Medicine.Annotated and edited transcript of a Witness Seminar held on 12 October 2004. Introduction by Professor Virginia Berridge, London School of Hygiene and Tropical Medicine.The 1974 reorganization of the National Health Service was largely seen as a disaster for the public health profession. The post of Medical Officer of Health, with its links to local government, was replaced by the community physician, located within health services. The technician-manager rather than the activist role predominated: community medicine doctors carried little weight by comparison with their clinical colleagues. Chaired by Professor Virginia Berridge this Witness Seminar examined the decline and rise of 'public health' both nationally and internationally in the 1980s and 1990s: the impact of the 1988 Acheson Report on public health medicine on a demoralized profession; the role of new ideas about health promotion imported from the international scene; the rise of evidence-based medicine and health services research, and their impact on public health; and the movement for multidisciplinary public health (MDPH) as a new avenue for public health from the 1990s. Participants included Professor Sir Donald Acheson, Professor John Ashton, Professor Nick Black, Professor David Blane, Dr Tim Carter, Sir Iain Chalmers, Dr Aileen Clarke, Dr June Crown, Dr Jeff French, Professor Alan Glynn, Ms Shirley Goodwin, Professor Rod Griffiths, Professor Walter Holland, Professor Klim McPherson, Dr Ornella Moscucci, Dr Geoffrey Rivett, Professor Alwyn Smith and Professor Ann Taket. Berridge V, Christie D A, Tansey E M. (eds) (2006) Public health in the 1980s and 1990s: Decline and rise? Wellcome Witnesses to Twentieth Century Medicine, vol. 26. London: The Wellcome Trust Centre for the History of Medicine at UCL.The Wellcome Trust Centre for the History of Medicine at UCL is funded by the Wellcome Trust, which is a registered charity, no. 210183

Non-equilibrium conductivity at quantum critical points

Quantum criticality provides an important route to revealing universal non-equilibrium behaviour. A canonical example of a quantum critical point is the Bose-Hubbard model, which we study under the application of an electric field. A Boltzmann transport formalism and $\epsilon$-expansion are used to obtain the non-equilibrium conductivity and current noise. This approach allows us to explicitly identify how a universal non-equilibrium steady state is maintained, by identifying the rate-limiting step in balancing Joule heating and dissipation to a heat bath. It also reveals that the non-equilibrium distribution function is very far from a thermal distribution.Comment: 5 pages, 2 figure

An Irregular Grid Approach for Pricing High-Dimensional American Options

We propose and test a new method for pricing American options in a high-dimensional setting.The method is centred around the approximation of the associated complementarity problem on an irregular grid.We approximate the partial differential operator on this grid by appealing to the SDE representation of the underlying process and computing the root of the transition probability matrix of an approximating Markov chain.Experimental results in five dimensions are presented for four different payoff functions.option pricing;inequality;markov chains

Pricing High-Dimensional American Options Using Local Consistency Conditions

We investigate a new method for pricing high-dimensional American options. The method is of finite difference type but is also related to Monte Carlo techniques in that it involves a representative sampling of the underlying variables.An approximating Markov chain is built using this sampling and linear programming is used to satisfy local consistency conditions at each point related to the infinitesimal generator or transition density.The algorithm for constructing the matrix can be parallelised easily; moreover once it has been obtained it can be reused to generate quick solutions for a large class of related problems.We provide pricing results for geometric average options in up to ten dimensions, and compare these with accurate benchmarks.option pricing;inequality;markov chains