Effect of the high-level trigger for detecting long-lived particles at LHCb

Area of Science:

• High Energy Physics
• Particle Physics
• Experimental Physics

Background:

• Many extensions of the Standard Model predict the existence of long-lived particles (LLPs).
• Detecting LLPs is challenging due to their significantly displaced vertices.
• Current trigger algorithms in experiments like the Large Hadron Collider beauty (LHCb) face difficulties in efficiently identifying these particles.

Purpose of the Study:

• To evaluate the effectiveness of existing LHCb trigger algorithms for detecting LLPs.
• To adapt and enhance these algorithms to increase LHCb's sensitivity to undiscovered LLPs.
• To explore a specific model featuring a Higgs portal to a dark sector and discuss its sensitivity reach.

Main Methods:

• Analysis of trigger algorithms within the LHCb experiment, focusing on the scintillating fiber tracker (SciFi detector).
• Development of a dedicated algorithm to manage the high volume and combinatorial complexity of hits in the LHCb detector.
• Testing a Higgs portal model to a dark sector to assess sensitivity.

Main Results:

• The study evaluated the performance of LHCb trigger algorithms for LLP detection.
• A new dedicated algorithm was developed to handle the data challenges in track reconstruction.
• The potential for enhanced sensitivity to LLPs in the LHCb forward region was discussed.

Conclusions:

• The developed algorithm, upon full implementation, is expected to significantly increase statistics for LLP searches.
• This enhancement will improve sensitivity for analyses involving both new LLPs and Standard Model particles with large lifetimes.
• The adapted trigger system shows promise for future discoveries in the forward region of the LHCb detector.