Discovering the twin Higgs boson with displaced decays

Abstract

The Twin Higgs mechanism keeps the scalar sector of the Standard Model (SM) natural while remaining consistent with the non-observation of new colored particles at the Large Hadron Collider (LHC). In this construction the heavy twin Higgs boson provides a portal between the SM particles and the twin sector, but is quite challenging to discover at colliders. In the Fraternal Twin Higgs setup, where light twin quarks are absent, we study a novel discovery channel for the heavy twin Higgs boson by considering its decay to a pair of light Higgs bosons, one of which subsequently decays to glueball states in the twin sector, leading to displaced vertex signatures. We estimate the sensitivity of existing LHC searches in this channel, and assess the discovery potential of the high luminosity (HL) LHC. We show that the glueballs probed by these searches are outside the sensitivity of existing searches for exotic decays of the light Higgs boson. In addition, we demonstrate that the displaced signals we consider probe a region of heavy Higgs masses beyond the reach of prompt signals. We also comment on the possibility of probing the input parameters of the microscopic physics and providing a way to test the Twin Higgs mechanism with this channel.

Composite twin dark matter

“…These regions of the parameter space reduce the rates of Higgs production and decay into visible states below 80% of the SM prediction, which is the current bound: see Refs. [19,30,52]. Therefore we find that the allowed range of twin baryon masses is about 10-100 GeV.…”

Breaking mirror twin hypercharge

“…The twin Higgs scenario, like other pNGB Higgs models, predicts tree-level deviations from the SM Higgs couplings. The reduction in couplings by cos ϑ in both the mirror [33] and fraternal [13,40] limits can be discovered at hadron colliders, but may require a precision lepton machine for definitive results. The usual reductions are augmented in our scenario due to the mixing of the Higgs and radial mode of the mirror hypercharge scalar, denoted here as ρ.…”

“…This basic low energy set-up has been modified in several ways ways [13][14][15][16][17][18][19][20][21][22][23] and admits various UV completions [24][25][26][27][28][29][30][31][32]. Recent work has focused on collider signals at the LHC and future machines [33][34][35][36][37][38][39][40][41], as well as cosmological analyses [18,[42][43][44][45][46][47][48][49] including several dark matter candidates [50][51][52][53][54][55][56].…”

Freezing-in twin dark matter

“…These models have proved to be a boon for phenomenology. Among other things, they quite generally motivate looking for Higgs decays to longlived particles at colliders [22][23][24][25][26][27][28][29] and contain well-motivated dark matter (DM) candidates [30][31][32][33][34][35][36][37][38][39][40][41].…”