Journal Article

Triggering soft bombs at the LHC

Papucci, Michele, Griso, Simone Pagan, Knapen, Simon, Robinson, Dean J.

2017

Overview

A bstract Very high multiplicity, spherically-symmetric distributions of soft particles, with p T ∼ few×100 MeV, may be a signature of strongly-coupled hidden valleys that exhibit long, efficient showering windows. With traditional triggers, such ‘soft bomb’ events closely resemble pile-up and are therefore only recorded with minimum bias triggers at a very low efficiency. We demonstrate a proof-of-concept for a high-level triggering strategy that efficiently separates soft bombs from pile-up by searching for a ‘belt of fire’: a high density band of hits on the innermost layer of the tracker. Seeding our proposed high-level trigger with existing jet, missing transverse energy or lepton hardware-level triggers, we show that net trigger efficiencies of order 10% are possible for bombs of mass several × 100 GeV. We also consider the special case that soft bombs are the result of an exotic decay of the 125 GeV Higgs. The fiducial rate for ‘Higgs bombs’ triggered in this manner is marginally higher than the rate achievable by triggering directly on a hard muon from associated Higgs production.

• Publisher: Springer Berlin Heidelberg,Springer Nature B.V,Springer Berlin,SpringerOpen
• Subject: Bombs / Classical and Quantum Gravitation / Decay rate / Elementary Particles / Energy management / Hadron-Hadron scattering (experiments) / High energy physics / Physics / Physics and Astronomy / PHYSICS OF ELEMENTARY PARTICLES AND FIELDS / Quantum Field Theories / Quantum Field Theory / Quantum Physics / Regular Article - Experimental Physics / Relativity Theory / String Theory / Valleys