216 research outputs found
Software Tools for ILC Detector Studies
International audienceThis article presents a review on the main issues of the software and computing tools developed ILC Detector related studies. It works out common eïŹorts but also diïŹerences among the eïŹorts within the three diïŹerent regions in which the detector R&D is pursued. It outlines the main features of the software packages and highlights results which were obtained by studies obtained within the frameworks. The grid is constantly evolving to be the computing environment for the studies
A precise determination of top quark electroweak couplings at the ILC operating at 500 GeV
On behalf of the groups at IFIC and LAL and the ILD concept.International audienceTop quark production in the process e+e- -> ttbar at a future linear electron positron collider with polarised beams is a powerful tool to determine the scale of new physics. The presented study assumes a centre-of-mass energy of 500 GeV and an integrated luminosity of 500 fb-1 equally shared between the incoming beam polarisations of (Pe+, Pe-) = (+/-0.8,-/+0.3). Events are selected in which the top pair decays semi-leptonically. The study comprises the cross sections, the forward-backward asymmetry and the slope of the helicity angle asymmetry. The vector, axial vector and tensorial CP conserving couplings are separately determined for the photon and the Z^0 component. The sensitivity to new physics would be dramatically improved with respect to that expected from the LHC for electroweak couplings
Fast and reasonable Installation, Experience and Acceptance of a Remote Control Room
Remote control systems are becoming more and more important to give us the
flexibility to control facilities, provide assistance and intervene in case of
problems at any time and from every place. As a global operating group CALICE
[2] with approx. 220 members worldwide is dependent on using a remote control
system for shifts and monitoring of the data taking. CALICE has at present
installed its detector at Fermilab, Chicago, where will run test beam
experiments for the next year. The components of the remote control system and
kind of use are presented here.Comment: 4 page
Mechanisms of isothiocyanate detoxification in larvae of two belowground herbivores, Delia radicum and D. floralis (Diptera: Anthomyiidae)
International audienceLike aboveground herbivores, belowground herbivores are confronted with multiple plant defense mechanisms including complex chemical cocktails in plant tissue. Roots and shoots of Brassicaceae plants contain the two-component glucosinolate (GSL)-myrosinase defense system. Upon cell damage, for example by herbivore feeding, toxic and pungent isothiocyanates (ITCs) can be formed. Several aboveground-feeding herbivores have developed biochemical adaptation strategies to overcome the GSL-ITC defenses of their host plant. Whether belowground herbivores feeding on Brassica roots possess similar mechanisms has received little attention. Here, we analyze how two related belowground specialist herbivores detoxify the GSL-ITC defenses of their host plants. The larvae of the fly species Delia radicum and D. floralis are common pests and specialized herbivores on the roots of Brassicaceae. We used chemical analyses (HPLC-MS/MS and HPLC-UV) to examine how the GSL-ITC defense system is metabolized by these congeneric larvae. In addition, we screened for candidate genes involved in the detoxification process using RNAseq and qPCR. The chemical analyses yielded glutathione conjugates and amines. This indicates that both species detoxify ITCs using potentially the general mercapturic acid pathway, which is also found in aboveground herbivores, and an ITC-specific hydrolytic pathway previously characterized in microbes. Performance assays confirmed that ITCs negatively affect the survival of both species, in spite of their known specialization to ITC-producing plants and tissues, whereas ITC breakdown products are less toxic. Interestingly, the RNAseq analyses showed that the two congeneric species activate different sets of genes upon ITC exposure, which was supported by qPCR data. Based on our findings, we conclude that these specialist larvae use combinations of general and compound-specific detoxification mechanisms with differing efficacies and substrate preferences. This indicates that combining detoxification mechanisms can be an evolutionarily successful strategy to handle plant defenses in herbivores
JRA3 Electromagnetic Calorimeter Technical Design Report
This report describes the design of the prototype for an Silicon Tungsten electromagnetic calorimeter with unprecedented high granularity to be operated in a detector at the International Linear Collider (ILC). The R&D for the prototype is co-funded by the European Union in the FP6 framework within the so called EUDET project in the years 2006-2010. The dimensions of the prototype are similar to those envisaged for the final detector. Already at this stage the prototype features a highly compact design. The sensitive layers, the Very Front End Electronics serving 64 channels per ASIC and copper plates for heat draining are integrated within 2000 ÎŒm
Cooling dynamics of a dilute gas of inelastic rods: a many particle simulation
We present results of simulations for a dilute gas of inelastically colliding
particles. Collisions are modelled as a stochastic process, which on average
decreases the translational energy (cooling), but allows for fluctuations in
the transfer of energy to internal vibrations. We show that these fluctuations
are strong enough to suppress inelastic collapse. This allows us to study large
systems for long times in the truely inelastic regime. During the cooling stage
we observe complex cluster dynamics, as large clusters of particles form,
collide and merge or dissolve. Typical clusters are found to survive long
enough to establish local equilibrium within a cluster, but not among different
clusters. We extend the model to include net dissipation of energy by damping
of the internal vibrations. Inelatic collapse is avoided also in this case but
in contrast to the conservative system the translational energy decays
according to the mean field scaling law, E(t)\propto t^{-2}, for asymptotically
long times.Comment: 10 pages, 12 figures, Latex; extended discussion, accepted for
publication in Phys. Rev.
Production and Equilibration of the Quark-Gluon Plasma with Chromoelectric Field and Minijets
Production and equilibration of quark-gluon plasma are studied within the
color flux-tube model, at the RHIC and LHC energies. Non-Abelian relativistic
transport equations for quarks, antiquarks and gluons, are solved in the
extended phase space which includes coordinates, momenta and color. Before the
chromoelectric field is formed, hard and semihard partons are produced via
minijets which provide the initial conditions necessary to solve the transport
equations. The model predicts that in spite of the vast difference between the
RHIC and LHC incident energies, once the local equilibrium is reached, the
energy densities, the number densities and the temperatures at the two machines
may not be very different from each other. The minijet input significantly
alters the evolution of the deconfined matter, unless the color field is too
strong. For the input parameters used here the equilibration time is estimated
to be fm at RHIC and fm at LHC, measured from the instant
when the two colliding nuclei have just passed through each other. The
temperature at equilibration is found to be MeV at RHIC and MeV at LHC.Comment: version to appear in Phys. Rev. C; discussion enlarged to include
comparison with other models; conclusions unchanged; 14 single-spaced pages +
8 ps figure
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