A search for charged leptons with large impact parameters using 139 fb-1 of s=13 TeV pp collision data from the ATLAS detector at the LHC is presented, addressing a long-standing gap in coverage of possible new physics signatures. Results are consistent with the background prediction. This search provides unique sensitivity to long-lived scalar supersymmetric lepton partners (sleptons). For lifetimes of 0.1 ns, selectron, smuon, and stau masses up to 720, 680, and 340 GeV, respectively, are excluded at 95% confidence level, drastically improving on the previous best limits from LEP.
Aad, G., Abbott, B., Abbott, D.C., Abed Abud, A., Abeling, K., Abhayasinghe, D.K., et al. (2021). Search for Displaced Leptons in s =13 TeV pp Collisions with the ATLAS Detector. PHYSICAL REVIEW LETTERS, 127(5), 051802 [10.1103/PhysRevLett.127.051802].