Search for displaced vertices arising from decays of new heavy particles in 7 TeV pp collisions at ATLAS

Abstract

We present the results of a search for new, heavy particles that decay at a significant distance from their production point into a final state containing charged hadrons in association with a high-momentum muon. The search is conducted in a pp-collision data sample with a center-of-mass energy of 7 TeV and an integrated luminosity of 33 pb(-1) collected in 2010 by the ATLAS detector operating at the Large Hadron Collider. Production of such particles is expected in various scenarios of physics beyond the standard model. We observe no signal and place limits on the production cross-section of supersymmetric particles in an R-parity-violating scenario as a function of the neutralino lifetime. Limits are presented for different squark and neutralino masses, enabling extension of the limits to a variety of other models. (C) 2011 CERN. Published by Elsevier B.V. All rights reserved

Natural supersymmetry’s last hope:R-parity violation viaUDDoperators

“…At the LHC, decay lengths larger than 100 µm can be detected in principle by examining the distribution of the impact parameters [30] of the gluino decay products. If the decay length is too large, it is also possible to detect the gluino as a displaced vertex [31].…”

Excluding electroweak baryogenesis in the MSSM

“…It is already excluded if it decays promptly [51][52][53] or escapes the detector [54], but one could imagine it being hidden from direct stop searches somehow, for example by decaying via a displaced vertex [55].…”

Lepton Number Violation in Higgs Decay at LHC

“…3. We smear the reconstructed vertex with the p T −η dependent resolution of 20-40 µm, as reported in [52]. Since the typical background contains one prompt and one secondary muon, it is effective to cut on both short and long d T , on both muons.…”