New Physics at Polarized Hadronic Colliders

Concerning new physics beyond the Standard Model we explore the discovery and analysis potentials of polarized (hadronic) experiments and we compare with the unpolarized case. For discovery, beam polarization is helpful in the case of purely hadronic new interactions. In any case, beam polarization provides us a unique piece of information on the chiral and flavour structures.Comment: Latex file, 7 pages and 3 ps fig included with psfig.sty. To appear in the proceedings of the ECT* workshop ``The Spin Structure of the Proton and Polarized Collider Physics'', July 2001, Trento, Ital

Beyond the standard model physics at RHIC in polarized pp collision

A polarized hadron collider experiment must have a great discovery potential for a search of physics beyond the standard model. Experimental data of various symmetry tests at RHIC are going to be obtained within a few years. The author developed a simulation tool, studying a sensitivity of hunting contact interaction at RHIC by measuring parity violating spin asymmetries.Comment: 8 pages, 9 figure, Proc. of Praha-SPIN-200

Discovery potential for New Physics in view of the RHIC-Spin upgrade

In view of a possible upgrade of the RHIC-Spin program at BNL, concerning both the machine and the detectors, we give some predictions concerning the potentialities of New Physics detection with polarized proton beams. We focus on parity-violating asymmetries in one-jet production due to contact terms or to a new leptophobic neutral gauge boson. We comment on the main uncertainties and we compare with unpolarized searches at Tevatron.Comment: Latex file, 9 pages and 1 ps fig included with psfig.st

Preparation of tantalum carbide films by reaction of electrolytic carbon coating with the tantalum substrate

This article demonstrates that coatings of tantalum carbide can be obtained by electrodeposition of carbon in molten fluorides on a tantalum substrate as an alternative to the CVD process. The structural characteristics of the carbon deposited by the electrolytic route lead to a high reactivity of this element towards a tantalum cathode to produce tantalum carbide. Mutual reactivity was shown to be enhanced if tantalum plate is replaced by an electrodeposited layer of tantalum, where the fine microstructure provides a catalytic effec

Search and identification of Scalar and Vector Leptoquarks at HERA with polarization

We analyze the effects of Scalar and Vector Leptoquarks on various observables in electron (positron) - proton deep inelastic scattering. In view of the future program of the HERA collider, with a high luminosity and also with polarization, we present the constraints that can be reached using this facility for several Leptoquark scenarios. We address the question of the identification of the nature of a discovered Leptoquark. We emphasize the relevance of having polarized lepton and proton beams in order to disentangle completely the various Leptoquark models. This study is also relevant in the context of the TESLA$\times$HERA project.Comment: Version to appear in Eur.Phys.J.C. 3 typos have been correcte

Co-reduction of aluminium and lanthanide ions in molten fluorides : application to cerium and samarium extraction from nuclear waste

This work concerns the method of co-reduction process with aluminium ions in LiF–CaF2 medium (79–21 mol.%) on tungsten electrode for cerium and samarium extraction. Electrochemical techniques such as cyclic and square wave voltammetries, and potentiostatic electrolyses were used to study the co-reduction of CeF3 and SmF3 with AlF3. For each of these elements, specific peaks of Al–Ce and Al–Sm alloys formationwere observed by voltammetry aswell as peaks of pure cerium and aluminium, and pure samarium and aluminium respectively. The difference of potential measured between the solvent reduction and the alloy formation suggests expecting an extraction efficiency of 99.99% of each lanthanide by the process. Different intermetallic compounds were obtained for different potentiostatic electrolysis and were characterised by Scanning Electron Microscopy with EDS probe. The validity of the process was verified by carrying out cerium and samarium extractions in the form of Al–Ln alloy; the extraction efficiency was 99.5% for Ce(III) and 99.4% for Sm(III)