Sampling the $$\mu \nu $$SSM for displaced decays of the tau left sneutrino LSP at the LHC

Within the framework of the $$\mu \nu \mathrm{SSM}$$μνSSM, a displaced dilepton signal is expected at the LHC from the decay of a tau left sneutrino as the lightest supersymmetric particle (LSP) with a mass in the range 45–100 GeV. We compare the predictions of this scenario with the ATLAS search for long-lived particles using displaced lepton pairs in pp collisions, considering an optimization of the trigger requirements by means of a high level trigger that exploits tracker information. The analysis is carried out in the general case of three families of right-handed neutrino superfields, where all the neutrinos get contributions to their masses at tree level. To analyze the parameter space, we sample the $$\mu \nu $$μνSSM for a tau left sneutrino LSP with proper decay length $$c\tau > 0.1 \, \hbox {mm}$$cτ>0.1mm using a likelihood data-driven method, and paying special attention to reproduce the current experimental data on neutrino and Higgs physics, as well as flavor observables. The sneutrino is special in the $$\mu \nu \mathrm{SSM}$$μνSSM since its couplings have to be chosen so that the neutrino oscillation data are reproduced. We find that important regions of the parameter space can be probed at the LHC run 3.

DILEPTON ANALYSIS IN THE HADES SPECTROMETER FOR 12C+12C AT 2 AGEV

The identification of the light mesons in the HADES spectrometer is based on an invariant mass reconstruction of their decay into e+e- pairs. In the dilepton (e+e-) signal reconstruction, particularly important is the reduction of a huge combinatorial background arising from wrong combinations of e+ and e- to unlike sign pairs. Methods of the dilepton signal and combinatorial background reconstruction in the HADES spectrometer will be presented.

SUPERSYMMETRIC SIGNALS AT THE TEVATRON

The possibility of detecting SUSY signals arising from Wino and Zino production at the Tevatron is examined. If the Tevatron is operated at peak luminosity of 1031cm−2 sec −1 with full lepton detection capabilities, we estimate for a UA1 type apparatus that the trilepton signal is sensitive to Winos with mass up to ≈70–80 GeV , the dilepton signal up to ≈50–60 GeV and the monojet signal up to ≈45–50 GeV .