Squark and Gaugino Hadroproduction and Decays in Non-Minimal Flavour Violating Supersymmetry

We present an extensive analysis of squark and gaugino hadroproduction and decays in non-minimal flavour violating supersymmetry. We employ the so-called super-CKM basis to define the possible misalignment of quark and squark rotations, and we use generalized (possibly complex) charges to define the mutual couplings of (s)quarks and gauge bosons/gauginos. The cross sections for all squark-(anti-)squark/gaugino pair and squark-gaugino associated production processes as well as their decay widths are then given in compact analytic form. For four different constrained supersymmetry breaking models with non-minimal flavour violation in the second/third generation squark sector only, we establish the parameter space regions allowed/favoured by low-energy, electroweak precision, and cosmological constraints and display the chirality and flavour decomposition of all up- and down-type squark mass eigenstates. Finally, we compute numerically the dependence of a representative sample of production cross sections at the LHC on the off-diagonal mass matrix elements in the experimentally allowed/favoured ranges.Comment: 35 pages, 29 (partly colour) figures. Some typos corrected, wording of several paragraphs improved, version accepted by Nucl. Phys.

Model of mobile agents for sexual interactions networks

We present a novel model to simulate real social networks of complex interactions, based in a granular system of colliding particles (agents). The network is build by keeping track of the collisions and evolves in time with correlations which emerge due to the mobility of the agents. Therefore, statistical features are a consequence only of local collisions among its individual agents. Agent dynamics is realized by an event-driven algorithm of collisions where energy is gained as opposed to granular systems which have dissipation. The model reproduces empirical data from networks of sexual interactions, not previously obtained with other approaches.Comment: 6 pages, 8 figure

Riemann solvers and undercompressive shocks of convex FPU chains

We consider FPU-type atomic chains with general convex potentials. The naive continuum limit in the hyperbolic space-time scaling is the p-system of mass and momentum conservation. We systematically compare Riemann solutions to the p-system with numerical solutions to discrete Riemann problems in FPU chains, and argue that the latter can be described by modified p-system Riemann solvers. We allow the flux to have a turning point, and observe a third type of elementary wave (conservative shocks) in the atomistic simulations. These waves are heteroclinic travelling waves and correspond to non-classical, undercompressive shocks of the p-system. We analyse such shocks for fluxes with one or more turning points. Depending on the convexity properties of the flux we propose FPU-Riemann solvers. Our numerical simulations confirm that Lax-shocks are replaced by so called dispersive shocks. For convex-concave flux we provide numerical evidence that convex FPU chains follow the p-system in generating conservative shocks that are supersonic. For concave-convex flux, however, the conservative shocks of the p-system are subsonic and do not appear in FPU-Riemann solutions

On the Shape of the Tail of a Two Dimensional Sand Pile

We study the shape of the tail of a heap of granular material. A simple theoretical argument shows that the tail adds a logarithmic correction to the slope given by the angle of repose. This expression is in good agreement with experiments. We present a cellular automaton that contains gravity, dissipation and surface roughness and its simulation also gives the predicted shape.Comment: LaTeX file 4 pages, 4 PS figures, also available at http://pmmh.espci.fr

Real-Time MRI of Continent and Stress Incontinent Male Patients after Orthotopic Ileal Neobladder

Introduction: The aim of this study was to correlate anatomic differences with continence status in male patients after cystoprostatectomy and ileal neobladder using real-time magnetic resonance imaging. Patients and Methods: Anatomic differences of 14 male patients (7 daytime continent and 7 stress incontinent) with ileal neobladder were determined by measuring the orthogonal distance of the bladder neck to the pubococcygeal line (PCL) to correlate anatomic differences with continence status. Results: The median distance of the bladder neck to PCL was +5.4 mm in continent patients before voiding whereas in incontinent patients it was +2 mm (p = 0.012). During the Valsalva maneuver, the median distance in continent patients was +4 and in incontinent patients -3 mm (p = 0.003). At the end of micturition, the median distance was +2.3 mm in continent patients and -12 mm in incontinent patients (p = 0.002). Conclusions: The bladder neck in incontinent patients showed more pronounced mobility in relation to the PCL during micturition and the Valsalva maneuver as compared to continent patients. In addition, the ileal neobladder was positioned significantly lower in the pelvis of incontinent patients. These preliminary results suggest that a stable bladder neck may be an important factor to reach full continence in patients with ileal neobladder. Copyright (C) 2011 S. Karger AG, Base

Frequency Metrology on single trapped ions in the weak binding limit: The 3s1/2-3p3/2 transition in 24-Mg+

We demonstrate a method for precision spectroscopy on trapped ions in the limit of unresolved motional sidebands. By sympathetic cooling of a chain of crystallized ions we suppress adverse temperature variations induced by the spectroscopy laser that usually lead to a distorted line profle and obtain a Voigt profile with negligible distortions. We applied the method to measure the absolute frequency of the astrophysically relevant D2 transition in single 24-Mg+ ions and find 1072082934.33(16)MHz, a nearly 400fold improvement over previous results. Further, we find the excited state lifetime to be 3.84(10) ns.Comment: 4 pages, 5 figure

Action minimizing fronts in general FPU-type chains

We study atomic chains with nonlinear nearest neighbour interactions and prove the existence of fronts (heteroclinic travelling waves with constant asymptotic states). Generalizing recent results of Herrmann and Rademacher we allow for non-convex interaction potentials and find fronts with non-monotone profile. These fronts minimize an action integral and can only exists if the asymptotic states fulfil the macroscopic constraints and if the interaction potential satisfies a geometric graph condition. Finally, we illustrate our findings by numerical simulations.Comment: 19 pages, several figure

Flux corrected finite volume scheme for preserving scalar boundedness in reacting large-eddy simulations

Preserving scalar boundedness is an important prerequisite to performing large-eddy simulations of turbulent reacting flows. A number of popular combustion models use a conserved-scalar, mixture-fraction to parameterize reactions that, by definition, is bound between zero and one. To avoid unphysical clipping, the numerical scheme solving the conserved-scalar transport equation must preserve these bounds, while minimizing the amount of numerical diffusivity. To this end, a flux correction method is presented and applied to the quadratic-upwind biased interpolative convective scheme that ensures preservation of the scalar’s physical bounds while retaining the low numerical diffusivity of the original quadratic-upwind biased interpolative convective scheme. It is demonstrated that this bounded quadratic-upwind biased interpolative convective scheme outperforms the third-order weighted essentially nonoscillatory scheme in maintaining spatial accuracy and reducing numerical dissipation errors both in generic test cases as well as direct numerical simulation of canonical flows

Injection Locking of a Trapped-Ion Phonon Laser

We report on injection locking of optically excited mechanical oscillations of a single, trapped ion. The injection locking dynamics are studied by analyzing the oscillator spectrum with a spatially selective Fourier transform technique and the oscillator phase with stroboscopic imaging. In both cases we find excellent agreement with theory inside and outside the locking range. We attain injection locking with forces as low as 5(1)×10^(-24)  N so this system appears promising for the detection of ultraweak oscillating forces