We consider the production of resonant sleptons via R-parity Violation
followed by gauge decays to a charged lepton and a neutralino which then decays
via R-parity Violation. This gives a signature ...of two like-sign charged
leptons. We find a background at run II of 0.14 +/- 0.13 events with an
integrated luminosity of 2 fb^-1. This enables us to probe R-parity Violating
couplings of 2.10^-3 for slepton mass of 100 GeV and up to slepton masses of
300 GeV for R-parity Violating couplings of 10^-2.
We discuss local \R-symmetry as a potentially powerful new model building tool. We first review and clarify that a \(U(1)\) \R-symmetry can only be gauged in local and not in global supersymmetry. We ...determine the anomaly-cancellation conditions for the gauged \R-symmetry. For the standard superpotential these equations have {\it no} solution, independently of how many Standard Model singlets are added to the model. There is also no solution when we increase the number of families and the number of pairs of Higgs doublets. When the Green-Schwarz mechanism is employed to cancel the anomalies, solutions only exist for a large number of singlets. We find many anomaly-free family-independent models with an extra \(SU(3)_c\) octet chiral superfield. We consider in detail the conditions for an anomaly-free {\it family dependent} \( U(1)_R\) and find solutions with one, two, three and four extra singlets. Only with three and four extra singlets do we naturally obtain sfermion masses of order the weak-scale. For these solutions we consider the spontaneous breaking of supersymmetry and the \(R\)-symmetry in the context of local supersymmetry. In general the \(U(1)_R\) gauge group is broken at or close to the Planck scale. We consider the effects of the \R-symmetry on baryon- and lepton-number violation in supersymmetry. There is no logical connection between a conserved \R-symmetry and conserved \R-parity. For conserved \R-symmetry we have models for all possibilities of conserved or broken \R-parity. Most models predict dominant effects which could be observed at HERA.
The supersymmetric extension of the standard model suffers from a problem of baryon-number violation. Discrete (and global) symmetries introduced to protect the proton are unstable under ...gravitational effects. We add a gauged \(U(1)_X\) to the standard model gauge group \(G_{SM}\) and require it to be anomaly-free. As new (chiral) superfields we only allow \(G_{SM}\)-singlets in order to maintain the good unification predictions. We find the most general set of solutions for the rational singlet charges. We embed our models in {\it local} supersymmetry and study the breaking of supersymmetry and \(U(1)_X\) to determine \(M_X\). We determine the full non-renormalizable and gauge invariant Lagrangian for the different solutions. We expect any effective theory to contain baryon- and lepton-number violating terms of dimension four suppressed by powers of \(M_X/M_{Pl}\). The power is predicted by the \(U(1)_X\) charges. We find consistency with the experimental bounds on the proton lifetime and on the neutrino masses. We also expect all supersymmetric models to have an unstable but longlived lightest supersymmetric particle. Consistency with underground experiments on upward going muons leads to stricter constraints than the proton decay experiments. These are barely satisfied.
We study the colour connection structure of R-parity violating decays and production cross sections, and construct a Monte Carlo simulation of these processes including colour coherence effects. We ...then present some results from the implementation of these processes in the HERWIG Monte Carlo event generator. We include the matrix elements for the two-body sfermion and three-body gaugino and gluino decays as well as the two-to-two resonant hard production processes in hadron-hadron collisions.
We consider the resonant production of charged sleptons at the LHC via R-parity violation followed by gauge decays to a charged lepton and a neutralino which then decays via R-parity violation. This ...gives a signature of two like-sign charged leptons. In the simulation we include the full hadronisation via Monte Carlo programs. We find a background, after cuts, of 5.1+/-2.5 events for an integrated luminosity of 10 fb^-1. A preliminary study of the signal suggests that couplings of 2.10^-3 for a smuon mass of 223 GeV and smuon masses of up to 540 GeV for couplings of 10^-2 can be probed.
We consider the production of resonant sleptons via R-parity Violation followed by gauge decays to a charged lepton and a neutralino which then decays via R-parity Violation. This gives a signature ...of two like-sign charged leptons. We find a background at run II of 0.14 +/- 0.13 events with an integrated luminosity of 2 fb^-1. This enables us to probe R-parity Violating couplings of 2.10^-3 for slepton mass of 100 GeV and up to slepton masses of 300 GeV for R-parity Violating couplings of 10^-2.
The purpose of this study was to investigate the localization and transport of uteroglobin in normal rabbit blastocysts (day 4-day 6 p.c.) and in those cultured for 6-48 h in vitro, using a specific ...radioimmunoassay and immunocytochemistry. The results of the radioimmunoassay showed that in day 4 p.c. blastocyst tissue (based on homogenate measurements) a significant decrease of the uteroglobin content started after only 6 h of culture in vitro. A significant concomitant rise of uteroglobin was observed in the culture medium after 12 h of in vitro culture. Using immunocytochemistry it was not possible to detect uteroglobin in any compartment of the non-cultured or in vitro cultured day 4 p.c. blastocysts. The efflux of uteroglobin down a concentration gradient was confirmed by the immunocytochemistry in non-cultured and in vitro cultured day 5 p.c. and day 6 p.c. blastocysts. Uteroglobin immunoreactions were mainly detected in non-cultured blastocysts (day 5 and 6 p.c.) in large vesicles of the trophoblast cells. In addition endocytotic vesicles at the inside of the apical membrane of trophoblast cells, some cell debris within the perivitelline space and the neozona were labelled. During in vitro culture of day 5 and 6 p.c. blastocysts, uteroglobin labelling in the coverings did not change. In non-cultured and cultured day 5 and 6 p.c. blastocysts neither the compartments of the embryoblast, the endoderm cells nor the blastocyst cavity showed any uteroglobin immunoreactions. After only 6 h of in vitro culture, uteroglobin immunoreactions were no longer found within the trophoblast cells. The reaction did not reappear during the course of in vitro culture up to 48 h, suggesting a complete lack of de novo synthesis of uteroglobin by blastocysts.
