Testing the OPERA Superluminal Neutrino Anomaly at the LHC Page: 2 of 7
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The OPERA collaboration  has recently reported that the muon neutrinos from the
CERN CNGS beam travel the approximately 730 km distance to Gran Sasso Laboratory at a
speed v, that exceeds the speed of light c, with (vv-c)/c = [2.48+0.28 (stat.)+0.30 (sys.)] x
10i5. This result, if confirmed, would be one of the most significant discoveries of recent
times and would have important implications for fundamental physics. However, many
observational considerations point to severe tensions between the OPERA result and well-
established phenomena regarding neutrinos, such as flavor oscillations and the Supernova
(SN) 1987a explosion [2, 3], among others . It is thus important to subject this "anomaly"
to as many tests as possible.
Cohen and Glashow  have very recently made the important observation that if a neu-
trino can travel faster than light several processes that are kinematically forbidden, within
the current Lorentz invariant framework, would become allowed. In particular, Ref. 
showed that bremsstrahlung processes in which superluminal neutrinos emit particles in
vacuo and lose energy would lead to a severe depletion of the beam above about 12.5 GeV
at Gran Sasso, in stark conflict with the reported OPERA data . Assuming a flavor
independent neutrino velocity vv, with negligible energy dependence, the leading process
relevant for the analysis in Ref.  was v - v, e+e-, mediated by a Z vector boson .
Inspired by the Cohen-Glashow (CG) analysis, we propose that the above vacuum
bremsstrahlung processes could also lead to detectable signals at the LHC, assuming that
the energy independence of v, will persist up to energies of order 100 GeV. This is a mild
assumption, given that the OPERA results show no significant energy dependence up to
about 50 GeV'. Our main observation is that decays of boosted top quarks at the LHC will
contain neutrinos with energy Ev > 100 GeV and such neutrinos would undergo CG vacuum
bremsstrahlung processes, leading to the appearance of (multiple) charged lepton pairs or
jets, with significantly displaced vertices, along the neutrino path.
Although our proposal is based on the mechanism considered in Ref. , the physi-
cal parameters characterizing the LHC experiments can in principle yield independent and
complementary tests of the OPERA anomaly. Obviously, the LHC would directly probe
the vacuum bremsstrahlung hypothesis, by searching for the emitted particles. In addition,
1 In fact, consistency with the SN 1897a data requires that v~ steeply increase with energy, above ~ 10 MeV.
However, we will assume that v~ has reached its asymptotic value near the GeV-scale and will not increase
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Davoudiasl, Hooman; /Brookhaven; Rizzo, Thomas G. & /SLAC. Testing the OPERA Superluminal Neutrino Anomaly at the LHC, article, March 15, 2012; United States. (digital.library.unt.edu/ark:/67531/metadc831710/m1/2/: accessed November 13, 2018), University of North Texas Libraries, Digital Library, digital.library.unt.edu; crediting UNT Libraries Government Documents Department.