Accélérateurs et nouveaux concepts d'accélération de particules

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The 10th Biennial Hatter Cardiovascular Institute workshop: cellular protection—evaluating new directions in the setting of myocardial infarction, ischaemic stroke, and cardio-oncology

Due to its poor capacity for regeneration, the heart is particularly sensitive to the loss of contractile cardiomyocytes. The onslaught of damage caused by ischaemia and reperfusion, occurring during an acute myocardial infarction and the subsequent reperfusion therapy, can wipe out upwards of a billion cardiomyocytes. A similar program of cell death can cause the irreversible loss of neurons in ischaemic stroke. Similar pathways of lethal cell injury can contribute to other pathologies such as left ventricular dysfunction and heart failure caused by cancer therapy. Consequently, strategies designed to protect the heart from lethal cell injury have the potential to be applicable across all three pathologies. The investigators meeting at the 10th Hatter Cardiovascular Institute workshop examined the parallels between ST-segment elevation myocardial infarction (STEMI), ischaemic stroke, and other pathologies that cause the loss of cardiomyocytes including cancer therapeutic cardiotoxicity. They examined the prospects for protection by remote ischaemic conditioning (RIC) in each scenario, and evaluated impasses and novel opportunities for cellular protection, with the future landscape for RIC in the clinical setting to be determined by the outcome of the large ERIC-PPCI/CONDI2 study. It was agreed that the way forward must include measures to improve experimental methodologies, such that they better reflect the clinical scenario and to judiciously select combinations of therapies targeting specific pathways of cellular death and injury

Stripping experiments in carbon foils with heavy ions in the energy range of 0.4-0.9 mev/a

We studied the properties of heavy ions stripped by carbon foils. Ni, I and Au ions of 0.4 - 0.9 MeV/A were used to bombard foils of 5 - 200 μg/cm 2. In these measurements the ions were detected in a Browne-Buechner spectrometer. We measured the angular straggling of the ions and the energy straggling. We looked for the behaviour of the foils under impact of large beam densities (several μAp/cm2 on an area of 1-2 mm2). We observed the thickness variations of the foils during bombardment in a vacuum of ∼ 10-6 and 10-7 torr. We looked for the evolution of the energy straggling during exposure and conclude that this parameter does not change in an important way. This means that neither thickening nor sputtering affects the homogeneity of the foil. Results on the lifetime of the bombarded foils are reported

Single WRW_R Production in e−e−e^-e^- Collisions at the NLC

Single $W_R$ production in $e^-e^-$ collisions at the NLC can be used to probe the Majorana nature of the heavy neutrinos present in the Left-Right Symmetric Model below the kinematic threshold for their direct production. For colliders in the $\sqrt {s}=1-1.5$ TeV range, typical cross sections of order $1-10 fb$ are obtained, depending on the specific choice of model parameters. Backgrounds arising from Standard Model processes are shown to be small. This analysis greatly extends the kinematic range of previous studies wherein the production of an on-shell, like-sign pair of $W_R$'s at the NLC was considered.Comment: 13pp, 3 figures (available on request), LaTex, SLAC-PUB-647

Measurement of fast and thermal neutron flux from the d + D reaction using the activation method

LPSC-acc ;

Upper bound on the scale of Majorana-neutrino mass generation

We derive a model-independent upper bound on the scale of Majorana-neutrino mass generation. The upper bound is $4\pi v^2/\sqrt 3 m_\nu$, where $v \simeq 246$ GeV is the weak scale and $m_\nu$ is the Majorana neutrino mass. For neutrino masses implied by neutrino oscillation experiments, all but one of these bounds are less than the Planck scale, and they are all within a few orders of magnitude of the grand-unification scale.Comment: 6 pages, 3 figures; REVTeX; published versio

The Noncommutative Standard Model and Forbidden Decays

In this contribution we discuss the Noncommutative Standard Model and the associated Standard Model-forbidden decays that can possibly serve as an experimental signature of space-time noncommutativity.Comment: 15 pages, 1 figure, Invited talk at 9th Adriatic Meeting and Central European Symposia on Particle Physics and The Universe, Dubrovnik, Croatia, 4-14 Sep 200

Selectron production at an e-e- linear collider with transversely polarized beams

We study selectron production at an e-e- linear collider. With the help of transverse beam polarizations, we define CP sensitive observables in the production process e- e- --> selectron_L selectron_R. This process proceeds via t-channel and u-channel exchange of neutralinos, and is sensitive to CP violation in the neutralino sector. We present numerical results and estimate the significances to which the CP sensitive observables can be measured.Comment: 14 page

The detection of neutron clusters

A new approach to the production and detection of bound neutron clusters is presented. The technique is based on the breakup of beams of very neutron-rich nuclei and the subsequent detection of the recoiling proton in a liquid scintillator. The method has been tested in the breakup of 11Li, 14Be and 15B beams by a C target. Some 6 events were observed that exhibit the characteristics of a multineutron cluster liberated in the breakup of 14Be, most probably in the channel 10Be+4n. The various backgrounds that may mimic such a signal are discussed in detail.Comment: 11 pages, 12 figures, LPCC 01-1

One-loop chiral amplitudes of Moller scattering process

The high energy amplitudes of the large angles Moller scattering are calculated in frame of chiral basis in Born and 1-loop QED level. Taking into account as well the contribution from emission of soft real photons the compact relations free from infrared divergences are obtained. The expressions for separate chiral amplitudes contribution to the cross section are in agreement with renormalization group predictions.Comment: 15 pages, 3 figure