Study of a soft lander/support module for Mars missions. Volume 3 - Appendixes Final summary report

Soft lander support module for Mars missions - lunar module radar evaluation and vernier phase simulatio

Simple model for decay of superdeformed nuclei

Recent theoretical investigations of the decay mechanism out of a superdeformed nuclear band have yielded qualitatively different results, depending on the relative values of the relevant decay widths. We present a simple two-level model for the dynamics of the tunneling between the superdeformed and normal-deformed bands, which treats decay and tunneling processes on an equal footing. The previous theoretical results are shown to correspond to coherent and incoherent limits of the full tunneling dynamics. Our model accounts for experimental data in both the A~150 mass region, where the tunneling dynamics is coherent, and in the A~190 mass region, where the tunneling dynamics is incoherent.Comment: 4 page

Fit for work? Health, employability and challenges for the UK welfare reform agenda

This article introduces a special issue of Policy Studies entitled “Fit for work? Health, employability and challenges for the UK welfare reform agenda”. Growing from a shared concern over the need to expand the evidence base around the processes that led to large numbers of people claiming disability benefits in the UK, it brings together contributions from leading labour market and social policy researchers providing evidence and commentary on major reforms to Incapacity Benefit (IB) in the UK. This special issue address three key questions: what are the main causes of the long-term rise in the number of people claiming IBs; what will reduce the number of claimants; and what is likely to deliver policy effectively and efficiently? This introduction first explains and examines the challenges to reforms to IB in the UK, and then, in conclusion, highlights the answers to the previous three questions – first, labour market restructuring and marginalisation have driven the rise in numbers claiming IBs. Second, economic regeneration in the Britain’s less prosperous areas coupled with intensive and sustained supply-side support measures will bring numbers down. Third, delivery need to be flexible and tailored to individual needs and needs to be able to access local and expert knowledge in a range of organisations, including Job Centre Plus, the NHS as well as the private and voluntary sectors

Power Doppler sonography in tenosynovitis: significance of the peritendinous hypoechoic rim.

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/135464/1/jum1998172103.pd

Quantum Necking in Stressed Metallic Nanowires

When a macroscopic metallic wire is subject to tensile stress, it necks down smoothly as it elongates. We show that nanowires with radii comparable to the Fermi wavelength display remarkably different behavior. Using concepts from fluid dynamics, a PDE for nanowire shape evolution is derived from a semiclassical energy functional that includes electron-shell effects. A rich dynamics involving movement and interaction of kinks connecting locally stable radii is found, and a new class of universal equilibrium shapes is predicted.Comment: 4 pages, 3 postscript figures. New result on universal equilibrium shape

Simulations for the development of a ground motion model for induced seismicity in the Groningen gas field, the Netherlands

We present simulations performed for the development of a ground motion model for induced earthquakes in the Groningen gas field. The largest recorded event, with M3.5, occurred in 2012 and, more recently, a M3.4 event in 2018 led to recorded ground accelerations exceeding 0.1 g. As part of an extensive hazard and risk study, it has been necessary to predict ground motions for scenario earthquakes up to M7. In order to achieve this, while accounting for the unique local geology, a range of simulations have been performed using both stochastic and full-waveform finite-difference simulations. Due to frequency limitations and lack of empirical calibration of the latter approach, input simulations for the ground motion model used in the hazard and risk analyses have been performed with a finite-fault stochastic method. However, in parallel, extensive studies using the finite-difference simulations have guided inputs and modelling considerations for these simulations. Three approaches are used: (1) the finite-fault stochastic method, (2) elastic point- and (3) finite-source 3D finite-difference simulations. We present a summary of the methods and their synthesis, including both amplitudes and durations within the context of the hazard and risk model. A unique form of wave-propagation with strong lateral focusing and defocusing is evident in both peak amplitudes and durations. The results clearly demonstrate the need for a locally derived ground motion model and the potential for reduction in aleatory variability in moving toward a path-specific fully non-ergodic model

Resonant Photon-Assisted Tunneling Through a Double Quantum Dot: An Electron Pump From Spatial Rabi Oscillations

The time average of the fully nonlinear current through a double quantum dot, subject to an arbitrary combination of ac and dc voltages, is calculated exactly using the Keldysh nonequilibrium Green function technique. When driven on resonance, the system functions as an efficient electron pump due to Rabi oscillation between the dots. The pumping current is maximum when the coupling to the leads equals the Rabi frequency.Comment: 6 pages, REVTEX 3.0, 3 postscript figure

A non-Hermitian critical point and the correlation length of strongly correlated quantum systems

We study a non-Hermitian generalization of quantum systems in which an imaginary vector potential is added to the momentum operator. In the tight-binding approximation, we make the hopping energy asymmetric in the Hermitian Hamiltonian. In a previous article, we conjectured that the non-Hermitian critical point where the energy gap vanishes is equal to the inverse correlation length of the Hermitian system and we confirmed the conjecture for two exactly solvable systems. In this article, we present more evidence for the conjecture. We also argue the basis of our conjecture by noting the dispersion relation of the elementary excitation.Comment: 25 pages, 18 figure

Coulomb correlations effects on localized charge relaxation in the coupled quantum dots

We analyzed localized charge time evolution in the system of two interacting quantum dots (QD) (artificial molecule) coupled with the continuous spectrum states. We demonstrated that Coulomb interaction modifies relaxation rates and is responsible for non-monotonic time evolution of the localized charge. We suggested new mechanism of this non-monotonic charge time evolution connected with charge redistribution between different relaxation channels in each QD.Comment: 10 pages, 10 figure

Transport Properties of One-Dimensional Hubbard Models

We present results for the zero and finite temperature Drude weight D(T) and for the Meissner fraction of the attractive and the repulsive Hubbard model, as well as for the model with next nearest neighbor repulsion. They are based on Quantum Monte Carlo studies and on the Bethe ansatz. We show that the Drude weight is well defined as an extrapolation on the imaginary frequency axis, even for finite temperature. The temperature, filling, and system size dependence of D is obtained. We find counterexamples to a conjectured connection of dissipationless transport and integrability of lattice models.Comment: 10 pages, 14 figures. Published versio