Related papers: Observing Virtual LSPs at LEP II
Currently popular search strategies for supersymmetric particles may be significantly affected due to relatively light sneutrinos which decay dominantly into invisible channels. In certain cases the second lightest neutralino may also decay…
Relatively light sneutrinos, which are experimentally allowed, may significantly affect the currently popular search strategies for supersymmetric particles by decaying dominantly into an invisible channel. In certain cases the second…
Relatively light sneutrinos which are experimentally allowed and are not theoretically disfavoured may significantly affect the currently popular search strategies for supersymmetric particles by decaying dominantly into an invisible…
A complete phenomenological study of the next-to-lightest neutralino decays is performed in the MSSM. The widths and branching ratios for all the possible decay channels (including the radiative decay X0(2) --> X0(1) gamma and the decay…
We discuss the phenomenology of the lightest neutralino in models where an effective bilinear term in the superpotential parametrizes the explicit breaking of R-parity. We consider supergravity scenarios where the lightest supersymmetric…
We explore the techniques, cross sections and expected signal significance for detecting invisible and almost invisible particles at LEP2 and the NLC by means of a hard photon tag. Examples from supersymmetry include the lightest chargino…
We analyze the experimental data from the search for new particles at LEP 100 and obtain mass bounds for the neutralinos of the Next--To--Minimal Supersymmetric Standard Model (NMSSM). We find that for $\tan\beta \gsim 5.5$ a massless…
The radiative decay of the next-to-lightest neutralino into a lightest neutralino and a photon is analyzed in the MSSM. We find that significant regions of the supersymmetric parameter space with large radiative BR's (up to about 100%) do…
If the sneutrino mass is below the chargino mass, the dominant decay mode of the lightest chargino is via a two-body decay channel $\chi^{\pm}_1 \ra \tilde{\nu} + l^{\pm}$. Sneutrinos are invisible in $R$-parity conserving supersymmetric…
We extend the constrained minimal supersymmetric model (CMSSM) by adding a right-handed neutrino superfield ($\nu$CMSSM) which decouples close to the GUT scale. We study the effects of a right-handed neutrino on the low energy spectrum and…
We study the possible signals of the (M+1)SSM with a singlino LSP at LEP2. First we identify regions of the parameter space which are ruled out by negative results of sparticle searches in the context of the MSSM. In the remaining…
Searches for supersymmetric particles performed at LEP 1 and LEP 2 are reviewed. Using the MSSM with R-parity conservation as a reference model, the various analyses are briefly described, and the results are presented in terms of mass and…
In extended supersymmetric models with additional singlet Higgs fields displaced vertices could be observed if the decay width of the next-to-lightest supersymmetric particle becomes very small due to a singlino dominated LSP. We study the…
A thorough study is performed on pair production and signatures of supersymmetric neutralinos in the MSSM at LEP2. Particular attention is paid to the region of the SuSy parameter space where the associated production of lightest and…
We suppose that the lightest supersymmetric particle (LSP) in the minimal supersymmetric standard model (MSSM) is the dark matter. The bino-like LSP can decay through the SO(10) gauge interactions, if one right-handed (RH) neutrino…
We study the distribution of lepton pairs from the second lightest neutralino decay \tchi^0_2\to\tchi^0_1 l^+l^-. This decay mode is important to measure the mass difference between \tchi^0_2 and the lightest neutralino \tchi^0_1, which…
We analyze relevant signals expected at the LHC for a left sneutrino as the lightest supersymmetric particle (LSP). The discussion is carried out in the `$\mu$ from $\nu$' supersymmetric standard model ($\mu \nu$SSM), where the presence of…
We examine scenarios in the Next-to-Minimal Supersymmetric Standard Model (NMSSM), where pair-produced squarks and gluinos decay via two cascades, each ending in a stable neutralino as Lightest Supersymmetric Particle (LSP) and a Standard…
High energy electron-photon colliders provide unique opportunities for probing physics beyond the standard model. We have studied the experimental signatures for two supersymmetric scenarios, with the lightest supersymmetric particle (LSP)…
We study an extension of the minimal supersymmetric standard model (MSSM) with additional right-handed singlet neutrino superfields. While such an extension incorporates a mechanism for the neutrino mass, it also opens up the possibility of…