Search for massive long-lived particles decaying semileptonically in the LHCb detector

Area of Science:

• High Energy Physics
• Particle Physics
• Supersymmetry

Background:

• Searches for new physics beyond the Standard Model are crucial.
• Long-lived particles are predicted by various theoretical extensions.
• Proton-proton collisions provide a high-energy environment to produce exotic particles.

Purpose of the Study:

• To search for massive long-lived particles decaying into a muon and two quarks.
• To explore specific production mechanisms, including Higgs-like particle decays.
• To set limits on theoretical models, such as R-Parity violating supersymmetry.

Main Methods:

• Analysis of proton-proton collision data at 7 and 8 TeV.
• Selection of events with a muon and two quarks from particle decays.
• Exploration of particle masses from 20 to 80 GeV and lifetimes from 5 to 100 fs.
• Interpretation of results within supersymmetric models.

Main Results:

• No significant excess of events above the expected background was observed.
• Upper limits were placed on the production cross-sections for the searched particles.
• Limits were derived for neutralino production in R-Parity violating supersymmetric models.

Conclusions:

• The study constrains the parameter space for massive long-lived particles.
• The absence of a signal provides valuable information for theoretical model building.
• Further searches with increased luminosity and improved techniques may be warranted.