PT Journal
AU LHCb Collaboration (Aaij, Rea
   Garcia Martin, LM
   Henry, L
   Martinez-Vidal, F
   Oyanguren, A
   Remon Alepuz, C
   Ruiz Valls, P
   Ruiz Vidal, J
   Sanchez Mayordomo, C
TI Search for Dark Photons Produced in 13 TeV pp Collisions
SO Physical Review Letters
JI Phys. Rev. Lett.
PY 2018
BP 061801
EP 11pp
VL 120
IS 6
DI 10.1103/PhysRevLett.120.061801
LA English
AB Searches are performed for both promptlike and long-lived dark photons, A', produced in proton-proton collisions at a center-of-mass energy of 13 TeV, using A' -> mu(+)mu(-) decays and a data sample corresponding to an integrated luminosity of 1.6 fb(-1) collected with the LHCb detector. The promptlike A' search covers the mass range from near the dimuon threshold up to 70 GeV, while the long-lived A' search is restricted to the low-mass region 214 < mo(A') < 350 MeV. No evidence for a signal is found, and 90% confidence level exclusion limits are placed on the gamma-A' kinetic-mixing strength. The constraints placed on promptlike dark photons are the most stringent to date for the mass range 10.6 < m(A') < 70 GeV, and are comparable to the best existing limits for m(A') < 0.5 GeV. The search for long-lived dark photons is the first to achieve sensitivity using a displaced-vertex signature.
ER