Measurement of the Z gamma to nu nu-bar gamma production cross section in pp collisions at sqrt(s) = 8 TeV and limits on anomalous Z-Z-gamma and Z-gamma-gamma trilinear gauge boson couplings

Understand

A measurement of the Z gamma to nu nu-bar gamma production cross section in pp collisions at sqrt(s) = 8 TeV is presented, using data corresponding to an integrated luminosity of 19.6 inverse femtobarns collected with the CMS detector at the LHC.

• This measurement is based on the observation of events with large missing energy and with a single photon with transverse momentum above 145 GeV and absolute pseudorapidity in the range |eta| < 1.44.
• The measured Z gamma to nu nu-bar gamma production cross section, 52.7 +/- 2.1(stat) +/- 6.4 (syst) +/- 1.4 (lumi) fb, agrees well with the standard model prediction of 50.0 +2.4 -2.2 fb.
• A study of the photon transverse momentum spectrum yields the most stringent limits to date on the anomalous Z-Z-gamma and Z-gamma-gamma trilinear gauge boson couplings.