Search for long-lived charginos based on a disappearing-track signature using 136 fb$$^{-1}$$ of pp collisions at $$\sqrt{s}$$ = 13 TeV with the ATLAS detector

Abstract

A search for long-lived charginos produced either directly or in the cascade decay of heavy prompt gluino states is presented. The search is based on proton–proton collision data collected at a centre-of-mass energy of $$\sqrt{s}$$ s = 13 T$$\text {eV}$$ eV between 2015 and 2018 with the ATLAS detector at the LHC, corresponding to an integrated luminosity of 136 fb$$^{-1}$$ - 1 . Long-lived charginos are characterised by a distinct signature of a short and then disappearing track, and are reconstructed using at least four measurements in the ATLAS pixel detector, with no subsequent measurements in the silicon-microstrip tracking volume nor any associated energy deposits in the calorimeter. The final state is complemented by a large missing transverse-momentum requirement for triggering purposes and at least one high-transverse-momentum jet. No excess above the expected backgrounds is observed. Exclusion limits are set at 95% confidence level on the masses of the chargino and gluino for different chargino lifetimes. Chargino masses up to 660 (210) G$$\text {eV}$$ eV are excluded in scenarios where the chargino is a pure wino (higgsino). For charginos produced during the cascade decay of a heavy gluino, gluinos with masses below 2.1 T$$\text {eV}$$ eV are excluded for a chargino mass of 300 G$$\text {eV}$$ eV and a lifetime of 0.2 ns.

WIMP and FIMP dark matter in singlet-triplet fermionic model

“…4.2. Moreover, the lower value chosen for M ρ is in agreement with the disappearing track search limit from the LHC [19]. Additionally, the chosen sin α and M H 2 range are also in agreement with the LHC constraints which we discuss in section.…”

“…The color bar represents the variation in M N (Y ρ∆ ) LP (RP). The region above the green line (which corresponds to M ρ ± = 400 GeV) is ruled out by the LHC JHEP11(2022)133 36.1 fb −1 data from disappearing track searches [18] and the region above the magenta dashed line (which corresponds to M ρ ± = 580 GeV) is ruled out by an updated search with a higher luminosity 136 fb −1 data [19]. The red solid line represents the projected sensitivity of MATHUSLA taken from [44].…”

“…Therefore, inside the detector, the decay of the charged particle manifest itself as a disappearing track. In figure 2, we show the constraints in the plane M ρ ±τ ρ ± (the ρ ± lifetime) as obtained from ATLAS [18,19] and CMS [20] searches on disappearing tracks. In this figure, the green solid line represents the prediction for the lifetime of ρ ± in the νSTFM.…”

“…JHEP11(2022)133 [18,19] and CMS [20] detectors at LHC collider from disappearing charged track, respectively. The light green dot dashed line represents the projection for HL-LHC [21].…”

Charged dark matter in supersymmetric twin Higgs models

“…For the stau decay length between about 10 cm and 1 m LHC searches for disappearing charged tracks may become sensitive [53,54]. The upper limit on the production cross-section at the LHC with √ s = 13 TeV can be as small as about 10 fb for the decay length O(1) m [53] which corresponds to the production cross-section of the JHEP10(2022)057 200 GeV right-handed staus.…”