Long-Lived Light Mediators from Higgs boson Decay at HL-LHC, FCC-hh and a Proposal of Dedicated LLP Detectors for FCC-hh

Abstract

We study the pair production of the long-lived mediator particles from the decay of the SM Higgs boson and their subsequent decay into standard model particles. We compute the projected sensitivity, both model-independently and with a minimal model, of using the muon spectrometer of the CMS detector at the HL-LHC experiment for ggF, VBF, and Vh production modes of the Higgs boson and various decay modes of the mediator particle, along with dedicated detectors for LLP searches like CODEX-b and MATHUSLA. Subsequently, we study the improvement with the FCC-hh detector at the 100 TeV collider experiment for such long-lived mediators, again focusing on the muon spectrometer. We propose dedicated LLP detector designs for the 100 TeV collider experiment, DELIGHT (Detector for longlived particles at high energy of 100 TeV), and study their sensitivities.

Dedicated Triggers for Displaced Jets using Timing Information from Electromagnetic Calorimeter at HL-LHC

“…Several phenomenological studies explore the possibilities of LLP searches covering a wide range of models and signatures, such as those in Refs. [11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30]. Collaborations of two major general purpose detectors at LHC, CMS and ATLAS, have also been actively performing several BSM studies involving various LLP signatures.…”

Phenomenology of CP-even ALP

“…Note added: While completing this paper, we found Ref. [99] by Bhattacherjee and Matsumoto and Sengupta, who performed a careful and throughout study on the light mediator test via a displaced vertex search in the present or future hadron colliders. Indeed, the proposed DELIGHT in [99] provides a great opportunity to discover our CP-even ALP (toghether with the direct search of s in the 100TeV collider).…”

“…[99] by Bhattacherjee and Matsumoto and Sengupta, who performed a careful and throughout study on the light mediator test via a displaced vertex search in the present or future hadron colliders. Indeed, the proposed DELIGHT in [99] provides a great opportunity to discover our CP-even ALP (toghether with the direct search of s in the 100TeV collider). In contrast, we discussed the test and discrimination of the light dark sector in the context of future lepton colliders, by assuming a negligible background for a displaced vertex search.…”

Emerging jets displaced into the future

“…Particle phenomenologists have begun exploring the reach of a variety of these detectors for a wide class of models [35][36][37][38][39][40][41][42][43][44], sometimes comparing the reach across different detectors. In this work we take a similar approach, comparing the discovery reach of a broad class of these detectors for Emerging Jets (EJ) [45].…”