Search for supersymmetry via associated production of charginos and neutralinos in final states with three leptons

A search for associated production of charginos and neutralinos is performed using data recorded with the D0 detector at a p (p) over bar center-of-mass energy of 1.96 TeV at the Fermilab Tevatron Collider. This analysis considers final states with missing transverse energy and three charged leptons, of which at least two are electrons or muons. No evidence for supersymmetry is found in a data set corresponding to an integrated luminosity of 320 pb(-1). Limits on the product of the production cross section and leptonic branching fraction are set. For the minimal supergravity model, a chargino lower mass limit of 117 GeV at the 95% C.L. is derived in regions of parameter space with enhanced leptonic branching fractions

Measurement of sigma(p(p)over-bar -> Z)center dot Br(Z ->tau tau) at root s=1.96 TeV (vol 71, art no. 072004, 2005)

A change in estimated integrated luminosity (from 226 pb$^{-1} to 257 pb$^{-1}$leads to a corrected value for${\sigma (p \bar p \to Z) \cdot}$Br${(Z \to \tau \tau)}$of$209\pm13(stat.)\pm16(syst.)\pm13(lum) pb

Caballero Bonald : 'José Agustín Goytisolo ansiaba ser seductor'

Publicat a ABC

Search for doubly charged Higgs boson pair production in the decay to mu(+)mu(+)mu(-)mu(-) in p(p)over-bar collisions at root s=1.96 TeV

A search for pair production of doubly charged Higgs bosons in the process p (p) over bar -->H++H---->mu(+)mu(+)mu(-)mu(-) is performed with the D0 run II detector at the Fermilab Tevatron. The analysis is based on a sample of inclusive dimuon data collected at an energy of roots=1.96 TeV, corresponding to an integrated luminosity of 113 pb(-1). In the absence of a signal, 95% confidence level mass limits of M(H-L(+/-+/-))>118.4 GeV/c(2) and M(H-R(+/-+/-))>98.2 GeV/c(2) are set for left-handed and right-handed doubly charged Higgs bosons, respectively, assuming 100% branching into muon pairs

Sol-gel Synthesis of Titanium/Bismuth Oxide Coatings for Biocompatibility Applications on 316L Stainless Steel

Objectives: This study was carried out in order to establish the potential offered by the sol-gel method to obtain Titanium/ Bismuth oxide coatings on 316L Stainless Steel (SS) substrates in biocompatibility applications. Methods/Analysis: The stable sol was synthesized by using Bismuth nitrate (III) pentahydrate and Titanium (IV) butoxide. The coatings were deposited by spin-coating technique at 4000 rpm and characterized topographically by Scanning Electron Microscopy SEM and structurally by X-ray diffraction XRD. Through the techniques of polarization potentiodynamic curves and Electrochemical Impedance Spectroscopy (EIS), the anticorrosive response of the �ilms was evaluated. The thickness was then measured, and biocompatibility test was developed. Findings: It was found that the coatings with high composition of the precursor titanium (IV) butoxide offer the best results as an anticorrosive application. Likewise, the growth of cells was uniform on the �ilms indicating that the medium offered by the �ilms does not present active cytotoxicity and surpasses by a large number the cellular growth level compared to stainless steel. Applications /Improvement: 316L (SS) is very useful in implantology, for its low cost compared with other materials. The implanted steel suffers corrosion by the physiological �luids of body. Titanium/Bismuth coatings establish a barrier between body �luids and SS implant

Improved measurement of the top quark mass.

The standard model of particle physics contains parameters—such as particle masses—whose origins are still unknown and which cannot be predicted, but whose values are constrained through their interactions. In particular, the masses of the top quark (Mt) and W boson (MW)1 constrain the mass of the long-hypothesized, but thus far not observed, Higgs boson. A precise measurement of Mt can therefore indicate where to look for the Higgs, and indeed whether the hypothesis of a standard model Higgs is consistent with experimental data. As top quarks are produced in pairs and decay in only about 10-24 s into various final states, reconstructing their masses from their decay products is very challenging. Here we report a technique that extracts more information from each top-quark event and yields a greatly improved precision (of 5.3 GeV/c2) when compared to previous measurements2. When our new result is combined with our published measurement in a complementary decay mode3 and with the only other measurements available2, the new world average for Mt becomes4 178.0 4.3 GeV/c2. As a result, the most likely Higgs mass increases from the experimentally excluded5 value6 of 96 to 117 GeV/c2, which is beyond current experimental sensitivity. The upper limit on the Higgs mass at the 95% confidence level is raised from 219 to 251 GeV/c2