Search for charginos and neutralinos in final states with two boosted hadronically decaying bosons and missing transverse momentum in pp collisions at s=13  TeV with

Abstract

A search for charginos and neutralinos at the Large Hadron Collider using fully hadronic final states and missing transverse momentum is reported. Pair-produced charginos or neutralinos are explored, each decaying into a high-p T Standard Model weak boson. Fully hadronic final states are studied to exploit the advantage of the large branching ratio, and the efficient rejection of backgrounds by identifying the high-p T bosons using large-radius jets and jet substructure information. An integrated luminosity of 139 fb −1 of proton-proton collision data collected by the ATLAS detector at a center-of-mass energy of 13 TeV is used. No significant excess is found beyond the Standard Model expectation. Exclusion limits at the 95% confidence level are set on wino or higgsino production with various assumptions about the decay branching ratios and the type of lightest supersymmetric particle. A wino (higgsino) mass up to 1060 (900) GeV is excluded when the lightest supersymmetry particle mass is below 400 (240) GeV and the mass splitting is larger than 400 (450) GeV. The sensitivity to high-mass winos and higgsinos is significantly extended relative to previous LHC searches using other final states.

A theory of dark pions

“…Our signal matches this topology in the limit of very light neutralino LSP. The strongest sensitivity has been achieved, remarkably, in the all-hadronic + MET search by ATLAS [98], which outperforms analogous searches for 3 + MET and b b + MET. For degenerate Higgsinos χ and massless bino LSP, a bound m χ > 900 GeV (95% CL) was JHEP01(2022)122 obtained.…”

“…We have assumed the Q i are not mass-degenerate, which applies to all benchmark models considered in section 4 (for two degenerate Q i , the constraint strengthens to 1.2 TeV). Given the current Higgsino expected bound [98], we rescale the cross section by L/L with L, L = 139, 3000 fb −1 and derive M 1.3 TeV as our estimate of the (13 TeV) HL-LHC sensitivity.…”

EW SUSY production at the LHC

“…The first two searches discussed are the first SUSY searches with a fully-hadronic final state, at ATLAS [5] and CMS [6]. Following this an ATLAS search with a three-lepton final state is presented [7], and finally a four-𝑏-jet final state search from CMS [8].…”

“…The ATLAS fully-hadronic search [5] has a signature of two boosted bosons each decaying to a large-radius jet and 𝑝 miss T , following the diagrams shown in Figure 1. The search has extensive interpretations, for example the MSSM -considering many options of the NLSP and LSP identities -and a GMSB model.…”

Searches for electroweak production of supersymmetric particles with the ATLAS detector

“…As an example, a search in the fully-hadronic final state mode ("0 " analysis in the figure) [7] is discussed in this section. It employs a "boosted boson tagging" technique using the large-R jet substructure for the first time in the ATLAS SUSY analysis.…”