Programmes in transition - between closure and start. Review of programme developments: Winter-Summer 2007

The past six months have seen a shift in emphasis from the 2000-2006 to the 2007-2013 programmes. Programme managers and other implementing organisations have not only been negotiating draft programmes for 2007-2013 with European Commission staff, but have also been undertaking a range of tasks to prepare for implementing these programmes. A number of initiatives have also occurred at EU level, which direct policymakers’ attention forward to the EU budget review of 2008-2009 and beyond. In addition, ongoing efforts have been needed to ensure that the remaining funds under the 2000-2006 programmes are effectively absorbed, and that all technical preparations for programme closure are underway

Trial factors for the look elsewhere effect in high energy physics

When searching for a new resonance somewhere in a possible mass range, the significance of observing a local excess of events must take into account the probability of observing such an excess anywhere in the range. This is the so called "look elsewhere effect". The effect can be quantified in terms of a trial factor, which is the ratio between the probability of observing the excess at some fixed mass point, to the probability of observing it anywhere in the range. We propose a simple and fast procedure for estimating the trial factor, based on earlier results by Davies. We show that asymptotically, the trial factor grows linearly with the (fixed mass) significance

Aspects of Large N Gauge Theory Dynamics as Seen by String Theory

In this paper we explore some of the features of large N supersymmetric and nonsupersymmetric gauge theories using Maldacena's duality conjectures. We shall show that the resulting strong coupling behavior of the gauge theories is consistent with our qualitative expectations of these theories. Some of these consistency checks are highly nontrivial and give additional evidence for the validity of the proposed dualities.Comment: 31 pages, LaTeX, 11 eps figures, typos correcte

A meson-exchange piN model up to energies sqrt(s) < 2.0 GeV

A meson-exchange piN model, previously constructed using three-dimensional reduction scheme of the Bethe-Salpeter equation for a model Lagrangian involving \pi, \eta, N, \Delta, rho, and \sigma fields, is extended to energies up to 2 GeV by including the \eta N channel and all the four stars \pi N resonances up to the F-waves. The effects of other 2 pion channels are taken into account phenomenologically. The extended model gives an excellent fit to both piN phase shifts and inelasticity parameters in all channels up to the F-waves. However, a few of the extracted resonance parameters differ considerably from the PDG values.Comment: 5 pages, 1 figire, 1 table. Talk presented at the 18th International Conference on "Few-Body Problems in Physics", Aug. 21-26, 2006, Santos, Brazi

Coupled Dyson-Schwinger Equations and Effects of Self-Consistency

Using the $\sigma -\omega$ model as an effective tool, the effects of self-consistency are studied in some detail. A coupled set of Dyson-Schwinger equations for the renormalized baryon and meson propagators in the $\sigma -\omega$ model is solved self-consistently according to the dressed Hartree-Fock scheme, where the hadron propagators in both the baryon and meson self-energies are required to also satisfy this coupled set of equations. It is found that the self-consistency affects the baryon spectral function noticeably, if only the interaction with $\sigma$ mesons is considered. However, there is a cancellation between the effects due to the $\sigma$ and $\omega$ mesons and the additional contribution of $\omega$ mesons makes the above effect insignificant. In both the $\sigma$ and $\sigma -\omega$ cases the effects of self-consistency on meson spectral function are perceptible, but they can nevertheless be taken account of without a self-consistent calculation. Our study indicates that to include the meson propagators in the self-consistency requirement is unnecessary and one can stop at an early step of an iteration procedure to obtain a good approximation to the fully self-consistent results of all the hadron propagators in the model, if an appropriate initial input is chosen. Vertex corrections and their effects on ghost poles are also studied.Comment: 20 pages (include 5 tables), 17 figures (PostScript file

Gravitational lensing by p-branes

The scattering of R-R gauge bosons off of Dirichlet p-branes is computed to leading order in the string coupling. The results are qualitatively similar to those found in the scattering of massless NS-NS bosons: all p-branes with p >= 0 exhibit stringy properties, in particular the Regge behavior. Both the R-R and NS-NS scattering amplitudes agree in the limit of small momentum transfer with scattering off the extremal R-R charged p-brane solutions found in the low-energy supergravities. We interpret this as evidence that Dirichlet-branes are an exact world-sheet description of the extremal p-branes. The -1-brane (D-instanton) is a special object which, unlike all other Dirichlet-branes, exhibits point-like behavior. We find the R-R charged instanton solution to type IIB supergravity and confirm that the field theoretic scattering off of this solution miraculously reproduces the full stringy calculation. As an aside, we include a discussion of the entropy of non-extremal black holes in ten dimensions, produced by exciting the 0-brane. We show that, for large black holes, the entropy grows linearly with the black hole mass.Comment: LaTeX, 18 pages, 1 figure, uses psfig.sty, available from http://xxx.lanl.gov/ftp/hep-th/papers/macros/psfig.sty Final version to appear in Nuclear Physics

Determining and modelling a complete time-temperature-transformation diagram for a Pt-based metallic glass former through combination of conventional and fast scanning calorimetry

State of the art fast differential scanning calorimetry (FDSC) is used to complement conventional differential scanning calorimetry (DSC) studies about the isothermal time-temperature-transformation (TTT) diagram of the bulk metallic glass forming liquid Pt42.5Cu27Ni9.5P21 to allow a comprehensive study of the crystallization kinetics of this system over a broad temperature range. FDSC and DSC data align well in the low-temperature region of the crystallization nose but show distinct discrepancies in the high-temperature region as the FDSC studies reveal faster crystallization times. The results are mathematically described and discussed based on the Johnson-Mehl-Avrami-Kolmogorov (JMAK) equation. Thereby, either homogeneous or heterogeneous nucleation is assumed, depending on the respective experimental conditions in FDSC and DSC studies. With this approach, the complete TTT diagram can be modelled as superposition of two sequential JMAK fits

Wesson's IMT with a Weylian bulk

The foundations of Wesson's induced matter theory are analyzed. It is shown that the 5D empty bulk must be regarded rather as a Weylian space than as a Riemannian one.The framework of a Weyl-Dirac version of Wesson's theory is elaborated and discussed. The bulk possesses in addition to the metric tensor a Weylian connection vector as well Dirac's gauge function; there are no sources (mass, current) in the bulk. On the 4D brane one obtains a geometrically based unified theory of gravitation and electromagnetism with mass, currents and equations induced by the 5D bulkComment: 29 page

Relativistic Description of Exclusive Deuteron Breakup Reactions

The exclusive deuteron break-up reaction is analyzed within a covariant approach based on the Bethe-Salpeter equation with realistic meson-exchange interaction. Relativistic effects in the cross section, tensor analyzing power and polarization transfer are investigated in explicit form. Results of numerical calculations are presented for kinematical conditions in forthcoming p + D reactions at COSY.Comment: 10 LaTeX pages, 4 eps-figure

Threshold pi^0 photo- and electro-production in a meson-exchange model

We show that, within a meson-exchange dynamical model describing well most of the existing pion electromagnetic production data up to the second resonance region, one is also able to obtain a good agreement with the pi^0 photo- and electroproduction data near threshold. In the case of pi^0 production, the effects of final state interaction in the threshold region are nearly saturated by single charge exchange rescattering. This indicates that in ChPT, it might be sufficient to carry out the calculation just up to one-loop diagrams for threshold neutral pion production.Comment: 6 pages LATEX including 1 tables and 4 figures, uses espcrc1.st