Do Macroeconomic Variables Affect the Agricultural Trade Sector? An Elasticities Analysis

International Relations/Trade,

Identifying the NMSSM by the interplay of LHC and ILC

The interplay between the LHC and the $e^+ e^-$ International Linear Collider (ILC) with $\sqrt{s}=500$ GeV might be crucial for the discrimination between the minimal and next-to-minimal supersymmetric standard model. We present an NMSSM scenario, where the light neutralinos have a significant singlino component, that cannot be distinguished from the MSSM by cross sections and mass measurements. Mass and mixing state predictions for the heavier neutralinos from the ILC analysis at different energy stages and comparison with observation at the LHC, lead to clear identification of the particle character and identify the underlying supersymmetric model.Comment: 8 pages, 2 eps figures, revtex4 style Contribution to the `2005 International Linear Collider Workshop - Stanford, U.S.A.

Photon collimator system for the ILC Positron Source

High energy e+e- linear colliders are the next large scale project in particle physics. They need intense sources to achieve the required luminosity. In particular, the positron source must provide about 10E+14 positrons per second. The positron source for the International Linear Collider (ILC) is based on a helical undulator passed by the electron beam to create an intense circularly polarized photon beam. With these photons a longitudinally polarized positron beam is generated; the degree of polarization can be enhanced by collimating the photon beam. However, the high photon beam intensity causes huge thermal load in the collimator material. In this paper the thermal load in the photon collimator is discussed and a flexible design solution is presented.Comment: 22 pages, 19 figures, 8 tables, cross-reference to table 4 fixe

Interference of Higgs boson resonances in mu^+ mu^- -> neutralino_i neutralino_j with longitudinal beam polarization

We study the interference of resonant Higgs boson exchange in neutralino production in \mu^+ \mu^- annihilation with longitudinally polarized beams. We use the energy distribution of the decay lepton in the process \neutralino_j \to \ell^\pm \slepton^\mp to determine the polarization of the neutralinos. In the CP conserving Minimal Supersymmetric Standard Model a non-vanishing asymmetry in the lepton energy spectrum is caused by the interference of Higgs boson exchange channels with different CP eigenvalues. The contribution of this interference is large if the heavy neutral bosons H and A are nearly degenerate. We show that the asymmetry can be used to determine the couplings of the neutral Higgs bosons to the neutralinos. In particular, the asymmetry allows to determine the relative phase of the couplings. We find large asymmetries and cross sections for a set of reference scenarios with nearly degenerate neutral Higgs bosons.Comment: 20 pages, 6 figures, minor typos corrected, to appear in Eur. Phys. J.

Helmet and active streamers from radio observations

Large coronal regions disconnected from any calcium plages and identified by their thermal emission at 169 mHz play a basic role in the sector structure of the interplanetary medium. It was concluded that these coronal regions are to be interpreted as streamers

Variations spatiotemporelles des compartiments autotrophes et hétérotrophes de la boucle microbienne dans les lacs du sud du Québec

Les variations de la biomasse des compartiments autotrophes et hétérotrophes de la boucle microbienne ont été examinées dans neuf lacs de deux régions du sud du Québec. Six lacs étaient situés dans les Laurentides et trois lacs dans les Cantons de l'Est. Ils se différenciaient en fonction de leur statut trophique, de la géologie du bassin versant, et de la physicochimie des eaux. Dans chaque lac, l'échantillonnage a été réalisé à trois profondeurs correspondant aux strates épi-, méta- et hypolimnétiques et à cinq dates au cours de l'été (1990-1992). Les biomasses moyennes de picoplancton autotrophe (PPA : 16-80 µg·C·L-1), de picoplancton hétérotrophe (PPH : 97-647 µg·C·L-1), de nanoplancton autotrophe (NPA : 7-37 µg·C·L-1) et de nanoplancton hétérotrophe (NPH : 9-29 µg·C·L-1) notées dans les lacs du sud du Québec le long d'un gradient trophique de PT variant de 7 à 73 µg·L-1 étaient du même ordre de grandeur que celles rapportées pour d'autres écosystèmes d'eau douce au Canada.La majeure partie de la variation dans les biomasses des compartiments microbiens étaient reliée aux variations inter-lacs mais il existaient aussi des sources de variation significatives au sein des lacs, soit au niveau spatial entre les strates limnétiques ou au niveau temporel entre les dates d'échantillonnage durant l'été. Toutefois, les patrons de variation spatiotemporelle intra-lac variaient d'un lac à l'autre. Les variations inter-lacs de la biomasse des quatre compartiments microbiens ont été mises en relation avec les changements dans les concentrations de phosphore total (PT) et dans les densités de macrozooplancton. Le niveau trophique des lacs, exprimés en PT, et l'abondance du macrozooplancton avaient un effet sur les biomasses des compartiments picoplanctoniques. La biomasse de PPA et PPH décroissait dans les lacs eutrophes des Cantons de l'Est ayant des concentrations de PT supérieures à 20 µg·L-1 et dans les lacs ayant de fortes densités de macrozooplancton ou un faible rapport micro-macrozooplancton. Notre étude n'a pas mis clairement en évidence les effets du niveau trophique ou du macrozoopancton sur les compartiments nanoplanctoniques (NPA, NPH).The biomass of autotrophic and heterotrophic microbial compartments were measured in nine lakes in two regions of southern Quebec. Six lakes were located in the Laurentides while three lakes were situated in the Eastern Townships. They varied in trophic status, watershed geology, and water chemistry. Each lake was sampled at three depths, corresponding to the epi-, meta-, and hypolimnion strata, and at five dates over the summer season (1991-1992). The mean biomass of autotrophic picoplankton (PPA: 16-80 µg·C·L-1), heterotrophic picoplankton (PPH: 97-647 µg·C·L-1), autotrophic nanoplankton (NPA: 7-37 µg·C·L-1), and heterotrophic nanoplankton (NPH: 9-29 µg·C·L-1) found in Quebec lakes over a PT range of trophy varying from 7 to 73 µg·L-1 were of the same order as those reported in other freshwater environments in Canada.Most of the variation in the biomass of the four microbial compartments was related to among-lake variation. Some variation was also due to within-lake spatial variation among limnetic strata or temporal variation over the summer season. However, within-lake patterns of variation patterns were different among lakes. Among-lake variations in the biomass of the four microbial compartments were examined in relation to changes in total phosphorus concentrations (PT) and macrozooplankton densities between lakes. Both lake trophy, expressed by PT, and macrozooplankton abundance influence the biomass of picoplankton compartments. The biomass of PPA and PPH decline in the most eutrophic lakes of the Eastern Townships where PT > 20 µg·L-1. PPA and PPH biomass were also reduced in lakes with the highest density of macrozooplankton or with low micro-/macrozooplankton ratio. Our study did not clearly detected the effects of lake trophy or macrozooplankton on nanoplanktonic compartments

Normal tau polarisation as a sensitive probe of CP violation in chargino decay

CP violation in the spin-spin correlations in chargino production and subsequent two-body decay into a tau and a tau-sneutrino is studied at the ILC. From the normal polarisation of the tau, an asymmetry is defined to test the CP-violating phase of the higgsino mass parameter \mu. Asymmetries of more than \pm70% are obtained, also in scenarios with heavy first and second generation sfermions. Bounds on the statistical significances of the CP asymmetries are estimated. As a result, the normal tau polarisation in the chargino decay is one of the most sensitive probes to constrain or measure the phase \phi_\mu at the ILC, motivating further detailed experimental studies.Comment: 20 pages, 10 figures, gzipped tar fil