Interpretation of Higgs and SUSY searches in MSUGRA and GMSB models

Higgs and SUSY searches performed by the ALEPH experiment at LEP are interpreted in the framework of two constrained R-parity conserving models: minimal supergravity and minimal gauge mediated supersymmetry breaking. (4 refs)

Search for Light Higgs Boson in the Yukawa process

The Yukawa process e+e- --> f fbar h/A, where f is a tau lepton or a b quark, is used to search for light scalar or pseudoscalar Higgs bosons in the framework of general two-Higgs-doublet models. The analysis is based on the data sample collected by the ALEPH experiment at LEP at centre-of-mass energies at and around the Z peak. Since no deviation from the standard model expectations has been observed in the data, this search results in a new 95 excluded region of the (mA, tan beta) plane in any two-Higgs-doublet model

Higgs limits in the MSSM: beyond the benchmark

Up to now, the ALEPH limits on the MSSM neutral Higgs boson masses have been reported for specific sets of model parameters corresponding to the so-called minimal and maximal mixing configurations. An investigation of the robustness of these results is performed by means of a scan of the parameter space in which more than 30 million sets of m_0, m_1/2, mu, A_t, m_A and tan(beta) values are probed. In the low tan(beta) regime, the m_h limit obtained in the cases of minimal and maximal mixing is found to remain valid for 99.991341f the parameter sets explored. In the case of large tan(beta), and considering the limit on m_h + m_A, this fraction reduces to 99.

Search for R-Parity Violating Decays of Supersymmetric Particles in e+e−e^{+}e^{-} Collisions at Centre-of-Mass Energies near 183 GeV

Searches for pair-production of supersymmetric particles under the assumption that R-parity is violated via a single dominant $LL{\bar E}$, $LQ{\bar D}$ or ${\bar U} {\bar D} {\bar D}$ coupling are performed using the data collected by the \ALEPH\ collaboration at centre-of-mass energies of 181--184~\gev. The observed candidate events in the data are in agreement with the Standard Model expectations. Upper limits on the production cross-sections and lower limits on the masses of charginos, sleptons, squarks and sneutrinos are de rived

HE-LHC: The High-Energy Large Hadron Collider – Future Circular Collider Conceptual Design Report Volume 4

In response to the 2013 Update of the European Strategy for Particle Physics (EPPSU), the Future Circular Collider (FCC) study was launched as a world-wide international collaboration hosted by CERN. The FCC study covered an energy-frontier hadron collider (FCC-hh), a highest-luminosity high-energy lepton collider (FCC-ee), the corresponding 100 km tunnel infrastructure, as well as the physics opportunities of these two colliders, and a high-energy LHC, based on FCC-hh technology. This document constitutes the third volume of the FCC Conceptual Design Report, devoted to the hadron collider FCC-hh. It summarizes the FCC-hh physics discovery opportunities, presents the FCC-hh accelerator design, performance reach, and staged operation plan, discusses the underlying technologies, the civil engineering and technical infrastructure, and also sketches a possible implementation. Combining ingredients from the Large Hadron Collider (LHC), the high-luminosity LHC upgrade and adding novel technologies and approaches, the FCC-hh design aims at significantly extending the energy frontier to 100 TeV. Its unprecedented centre-of-mass collision energy will make the FCC-hh a unique instrument to explore physics beyond the Standard Model, offering great direct sensitivity to new physics and discoveries

Selected topics on searches at LEP

To depict the wide range of searches for new phenomena at LEP, three salient topics are reviewed: the search for the standard model Higgs boson, the mass limit for the lightest neutralino and searches for large extra dimensions. (5 refs)