6,058 research outputs found
The Baum-Connes Conjecture via Localisation of Categories
We redefine the Baum-Connes assembly map using simplicial approximation in
the equivariant Kasparov category. This new interpretation is ideal for
studying functorial properties and gives analogues of the assembly maps for all
equivariant homology theories, not just for the K-theory of the crossed
product. We extend many of the known techniques for proving the Baum-Connes
conjecture to this more general setting
Application to the SPIRAL project at GANIL of a new kind of large acceptance mass separator
International audienc
High intensity and space charge problems at GANIL
http://accelconf.web.cern.ch/AccelConf/c86/papers/g-04.pdfInternational audienceWe routinely accelerate up to micro-amperes of ionsat energies ranging from 25 to 95 MeV / A. Already atthese levels, space charge (S.C) problems drasticallyaffect the bunching efficiency between the ECRexternal ion-source and our Co compact injector.Moreover in the "2.5" version of GANIL we expectcurrents above 50 e\l A (Ar+6 for instance) and S.Ceffects will be of prime importance during accelerationin the injector and even in our first SSC. Wepresent our computer codes and our first results
Preliminary design of a new high intensity injection system for GANIL.
http://accelconf.web.cern.ch/AccelConf/c89/papers/f6-12.pdfInternational audienc
SPIRAL facility at GANIL : ion beam simulation and optimisation method for the CIME cyclotron injection system
International audienc
Effect of substrate thermal resistance on space-domain microchannel
In recent years, Fluorescent Melting Curve Analysis (FMCA) has become an almost ubiquitous feature of commercial quantitative PCR (qPCR) thermal cyclers. Here a micro-fluidic device is presented capable of performing FMCA within a microchannel. The device consists of modular thermally conductive blocks which can sandwich a microfluidic substrate. Opposing ends of the blocks are held at differing temperatures and a linear thermal gradient is generated along the microfluidic channel. Fluorescent measurements taken from a sample as it passes along the micro-fluidic channel permits fluorescent melting curves to be generated. In this study we measure DNA melting temperature from two plasmid fragments. The effects of flow velocity and ramp-rate are investigated, and measured melting curves are compared to those acquired from a commercially available PCR thermocycler
Dark Matter Search in the Edelweiss Experiment
Preliminary results obtained with 320g bolometers with simultaneous
ionization and heat measurements are described. After a few weeks of data
taking, data accumulated with one of these detectors are beginning to exclude
the upper part of the DAMA region. Prospects for the present run and the second
stage of the experiment, EDELWEISS-II, using an innovative reversed cryostat
allowing data taking with 100 detectors, are briefly described.Comment: IDM 2000, 3rd International Workshop on the Identification of Dark
Matter, York (GB), 18-22/09/2000, v2.0 minor modification
Multi-Jet Event Rates in Deep Inelastic Scattering and Determination of the Strong Coupling Constant
Jet event rates in deep inelastic ep scattering at HERA are investigated
applying the modified JADE jet algorithm. The analysis uses data taken with the
H1 detector in 1994 and 1995. The data are corrected for detector and
hadronization effects and then compared with perturbative QCD predictions using
next-to-leading order calculations. The strong coupling constant alpha_S(M_Z^2)
is determined evaluating the jet event rates. Values of alpha_S(Q^2) are
extracted in four different bins of the negative squared momentum
transfer~\qq in the range from 40 GeV2 to 4000 GeV2. A combined fit of the
renormalization group equation to these several alpha_S(Q^2) values results in
alpha_S(M_Z^2) = 0.117+-0.003(stat)+0.009-0.013(syst)+0.006(jet algorithm).Comment: 17 pages, 4 figures, 3 tables, this version to appear in Eur. Phys.
J.; it replaces first posted hep-ex/9807019 which had incorrect figure 4
Multiplicity Structure of the Hadronic Final State in Diffractive Deep-Inelastic Scattering at HERA
The multiplicity structure of the hadronic system X produced in
deep-inelastic processes at HERA of the type ep -> eXY, where Y is a hadronic
system with mass M_Y< 1.6 GeV and where the squared momentum transfer at the pY
vertex, t, is limited to |t|<1 GeV^2, is studied as a function of the invariant
mass M_X of the system X. Results are presented on multiplicity distributions
and multiplicity moments, rapidity spectra and forward-backward correlations in
the centre-of-mass system of X. The data are compared to results in e+e-
annihilation, fixed-target lepton-nucleon collisions, hadro-produced
diffractive final states and to non-diffractive hadron-hadron collisions. The
comparison suggests a production mechanism of virtual photon dissociation which
involves a mixture of partonic states and a significant gluon content. The data
are well described by a model, based on a QCD-Regge analysis of the diffractive
structure function, which assumes a large hard gluonic component of the
colourless exchange at low Q^2. A model with soft colour interactions is also
successful.Comment: 22 pages, 4 figures, submitted to Eur. Phys. J., error in first
submission - omitted bibliograph
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