Search for chargino-neutralino production with mass splittings near the electroweak scale in three-lepton final states in s=13  TeV pp collisions with the ATLAS detec

Abstract

A search for supersymmetry through the pair production of electroweakinos with mass splittings near the electroweak scale and decaying via on-shell W and Z bosons is presented for a three-lepton final state. The analyzed proton-proton collision data taken at a center-of-mass energy of ffiffi ffi s p ¼ 13 TeV were collected between 2015 and 2018 by the ATLAS experiment at the Large Hadron Collider, corresponding to an integrated luminosity of 139 fb −1. A search, emulating the recursive jigsaw reconstruction technique with easily reproducible laboratory-frame variables, is performed. The two excesses observed in the 2015-2016 data recursive jigsaw analysis in the low-mass three-lepton phase space are reproduced. Results with the full data set are in agreement with the Standard Model expectations. They are interpreted to set exclusion limits at the 95% confidence level on simplified models of chargino-neutralino pair production for masses up to 345 GeV.

Does SUSY have friends? A new approach for LHC event analysis

“…Both gauge bosons are assumed to decay leptonically giving a 3-lepton final state, where the dominant background is SM diboson (WZ) production. This model was not excluded in the three-lepton search channel in the most recent 139 fb −1 analysis conducted by the ATLAS collaboration [29]. The results in this paper assume 150 fb −1 of integrated luminosity, which is comparable.…”

“…The five kinematic variables are shown in figure 3. The lower panel of each figure shows the binomial significance Z bi for either an upper cut or lower cut on the variable at the value given on the horizontal axis, assuming a total systematic uncertainty of 15% (chosen to be consistent with numbers quoted by the ATLAS run-2 searches in the 3-lepton channel [29,53]). This significance calculation also includes the statistical uncertainty of the background which is added to the systematic uncertainty in quadrature.…”

Vector boson fusion at multi-TeV muon colliders

“…This leads to the existence of a new degree of freedom for each SM one that is mass-degenerate but with opposite spin-statistics, and that order-by-order contribute oppositely to quantum corrections of the Higgs's mass. The lack of experimental evidence for superpartners [124][125][126][127][128][129][130][131][132][133], however, suggests that if SUSY is realized at a certain scale it is broken at the EW scale.…”

“…The mass eigenstates, denoted byχ 0 k andχ ± k , are given as linear combinations of the fields {B,W 0 ,H 0 d ,H 0 u } and {W + ,H + u ,W − ,H − d }, respectively. Despite extensive searches for these states [121][122][123][124][125], including direct searches at the LHC [126][127][128][129][130][131][132][133], evidence for the MSSM at the weak scale has yet be established. If the MSSM, or any variation of SUSY, is realized at the EW-or TeV-scale, then a multi-TeV muon collider could be an optimal machine to discover missing superparticles or study the spectrum properties.…”

Dark Matter Constraints and the Neutralino Sector of the scNMSSM

“…A well-motivated candidate for DM is the neutralino lightest supersymmetric particle (LSP) in supersymmetric (SUSY) models [7]. However, such models are being challenged by recent null results from experiments, including DM searches [8][9][10][11][12][13]. DM searches can be categorized into collider, direct detection, and indirect detection searches.…”