Conformal Orthosymplectic Quantum Mechanics

We present the most general curvature obstruction to the deformed parabolic orthosymplectic symmetry subalgebra of the supersymmetric quantum mechanical models recently developed to describe Lichnerowicz wave operators acting on arbitrary tensors and spinors. For geometries possessing a hypersurface-orthogonal homothetic conformal Killing vector we show that the parabolic subalgebra is enhanced to a (curvature-obstructed) orthosymplectic algebra. The new symmetries correspond to time-dependent conformal symmetries of the underlying particle model. We also comment on generalizations germane to three dimensions and new Chern--Simons-like particle models.Comment: 27 pages LaTe

Anticardiolipin antibodies and coronary heart disease

Arterial or venous thrombotic events have been described as complications in patients with positive anticardiolipin antibodies (aCL), affecting various organs including the heart. In order to see whether aCL could be, among others, a predisposing factor for coronary artery occlusions and whether it could serve as a prognostic marker for coronary heart disease, 232patients enrolled in the European Concerted Action on Thrombosis Angina Pectoris Study were studied. aCL and various other haemostatic parameters were determined at time of admittance in order to see whether a relationship existed between haemostasis at baseline and extent or prognosis of the cardiovascular disease. A follow-up at 12 and 24 months after angiography included information about relapsing coronary or other thrombotic events, treatment and outcome of the disease. aCL were not found to be a marker of either progressive cardiovascular disease or recurrent thrombotic events. No correlation was found, either in aCL positive or in aCL negative patients, between high levels of haemostasis activation markers, such as fi-thromboglobulin, platelet factor 4 or fibrinopeptide A and recurrent cardiovascular diseas

Measurements of the effect of collisions on transverse beam halo diffusion in the Tevatron and in the LHC

Beam-beam forces and collision optics can strongly affect beam lifetime, dynamic aperture, and halo formation in particle colliders. Extensive analytical and numerical simulations are carried out in the design and operational stage of a machine to quantify these effects, but experimental data is scarce. The technique of small-step collimator scans was applied to the Fermilab Tevatron collider and to the CERN Large Hadron Collider to study the effect of collisions on transverse beam halo dynamics. We describe the technique and present a summary of the first results on the dependence of the halo diffusion coefficient on betatron amplitude in the Tevatron and in the LHC.Comment: 4 pages, 2 figures. Submitted to the Proceedings of the ICFA Mini-Workshop on Beam-beam Effects in Hadron Colliders (BB2013), Geneva, Switzerland, 18-22 March 201

Towards a Notion of Distributed Time for Petri Nets

We set the ground for research on a timed extension of Petri nets where time parameters are associated with tokens and arcs carry constraints that qualify the age of tokens required for enabling. The novelty is that, rather than a single global clock, we use a set of unrelated clocks --- possibly one per place --- allowing a local timing as well as distributed time synchronisation. We give a formal definition of the model and investigate properties of local versus global timing, including decidability issues and notions of processes of the respective models

MSSM predictions of the neutral Higgs boson masses and LEP II production cross sections

Within the framework of the Minimal Supersymmetric Standard Model (MSSM) the Higgs masses and LEP II production cross sections are calculated for a wide range of the parameter space. In addition, the parameter space restricted by unification, electroweak symmetry breaking and other low energy constraints is considered in detail, in which case the masses of all SUSY partners can be estimated, so that their contributions to the radiative corrections can be calculated. Explicit analytical formulae for these contribution are derived. The radiative corrections from the Yukawa couplings of the third generation are found to dominate over the contributions from charginos and neutralinos. Large Higgs mass uncertainties are due to the top mass uncertainty and the unknown sign of the Higgs mixing parameter. For the low tanb scenario the mass of the lightest Higgs is found to be below 103 GeV for a top mass below 190 GeV. The cross section at a LEP energy of 192 GeV is sufficient to find or exclude this low tanb scenario for a top mass below 180 GeV. For the high tanb scenario only a small fraction of the parameter space can be covered, since the Higgs mass is predicted between 105 and 125 GeV in most cases. At the theoretically possible LEP II energy of 205 GeV part of the parameter space for the large tanb scenario would be accessible

Beam diffusion measurements using collimator scans in the LHC

The time evolution of beam losses during a collimator scan provides information on halo diffusion and population. This is an essential input for machine performance characterization and for the design of collimation systems. Beam halo measurements in the CERN Large Hadron Collider were conducted through collimator scrapings in a dedicated beam study for the first time at 4 TeV. Four scans were performed with two collimators, in the vertical plane for beam 1 and horizontally for beam 2, before and after bringing the beams into collisions. Inward and outward steps were performed. A diffusion model was used to interpret the observed loss rate evolution in response to the collimator steps. With this technique, diffusion coefficients were estimated as a function of betatron oscillation amplitude from approximately 3 to 7 standard deviations of the transverse beam distribution. A comparison of halo diffusion and core emittance growth rates is also presented.peer-reviewe

The Gulf Stream Front, Its Role in Larval Fish Survival and Recruitment in Florida: Hydrographic Station and Plankton Data

The goal of this project was to develop a clearer understanding of the role that the Gulf Stream system plays in larval fish survival and recruitment in Florida waters. The specific objectives of this study were to: Determine whether the biomass of fish larva, other zooplankton, microzooplankton and phytoplankton is higher at the shoreward front of the Gulf Stream than on either side of it. Characterize the assemblages of fish larvae predators and prey both at the front and on either side of it. Determine if the composition, abundance and size frequency distribution of larval and juvenile fishes in the front is different from that in the coastal zone or in the Gulf Stream. Monitor the position of the Gulf Stream by continuous measurements of physical variables at moorings located in the Gulf Stream off Fort Lauderdale and within Port Everglades. This project was a first effort to characterize the coupling between physical and biological processes that may influence the early life histories of fishes in Florida\u27s coastal waters. This report contains the hydrographic and plankton data from the project. It is intended to facilitate data access by the scientific and management communities. Interpretations and detailed analyses of these data are being given in meeting presentations, peer-reviewed journal articles (Stone et al. draft manuscript, Braker et al. draft manuscript, Frazel et al. in preparation) and graduate theses (Stone 1993; Braker 1993)