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Title: Search for long-lived neutral particles decaying to quark-antiquark pairs in proton-proton collisions at √s = 8 TeV

A search is performed for long-lived massive neutral particles decaying to quark-antiquark pairs. The experimental signature is a distinctive topology of a pair of jets, originating at a secondary vertex. Events were collected with the CMS detector at the CERN LHC in proton-proton collisions at a center-of-mass energy of 8 TeV. The data analyzed correspond to an integrated luminosity of 18.5 fb–1. No significant excess is observed above standard model expectations. Upper limits at 95% confidence level are set on the production cross section of a heavy neutral scalar particle, H, in the mass range of 200 to 1000 GeV, decaying promptly into a pair of long-lived neutral X particles in the mass range of 50 to 350 GeV, each in turn decaying into a quark-antiquark pair. For X with mean proper decay lengths of 0.4 to 200 cm, the upper limits are typically 0.5–200 fb. The results are also interpreted in the context of an R-parity-violating supersymmetric model with long-lived neutralinos decaying into a quark-antiquark pair and a muon. For pair production of squarks that promptly decay to neutralinos with mean proper decay lengths of 2–40 cm, the upper limits on the cross section are typically 0.5–3 fb. Asmore » a result, the above limits are the most stringent on these channels to date.« less
  1. Yerevan Physics Inst. (YerPhI), Yerevan (Armenia). et al.
Publication Date:
OSTI Identifier:
Report Number(s):
FERMILAB-PUB-14-568-CMS; CERN-PH-EP-2014-256; CMS-EXO-12-038
Journal ID: ISSN 1550-7998; PRVDAQ; arXiv eprint number arXiv:1411.6530; TRN: US1600950
Grant/Contract Number:
Published Article
Journal Name:
Physical Review. D, Particles, Fields, Gravitation and Cosmology
Additional Journal Information:
Journal Volume: 91; Journal Issue: 1; Journal ID: ISSN 1550-7998
American Physical Society (APS)
Research Org:
Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
Sponsoring Org:
USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
Contributing Orgs:
CMS Collaboration
Country of Publication:
United States