Search for long-lived particles decaying to jet pairs

Area of Science:

• High Energy Physics
• Particle Physics
• Collider Physics

Background:

• The Standard Model of particle physics describes fundamental particles and forces.
• Searches for new physics beyond the Standard Model are crucial for understanding the universe.
• Long-lived particles could indicate new fundamental forces or particles.

Purpose of the Study:

• To search for pair-produced long-lived particles originating from the decay of a Standard Model-like Higgs boson.
• To investigate a specific mass range (25-50 GeV) and lifetime range (1-200 ns) for these hypothetical particles.
• To set limits on the production cross-section of such particles at the Large Hadron Collider.

Main Methods:

• Analysis of proton-proton collision data collected by the LHCb detector.
• Utilizing an integrated luminosity of 0.62 fb⁻¹ at a center-of-mass energy of 13 TeV.
• Identifying the experimental signature of displaced vertices with two associated jets.

Main Results:

• No significant excess of events above the expected background was observed.
• Upper limits were placed on the production cross-section for long-lived particles.
• The limits are dependent on the mass and lifetime of the long-lived particles.

Conclusions:

• The search did not yield evidence for the existence of the targeted long-lived particles.
• The results constrain theoretical models predicting such particles in the studied mass and lifetime ranges.
• This study contributes to the ongoing quest for new physics beyond the Standard Model.