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

TL;DR

This paper measures the Z gamma to neutrino-antineutrino gamma production cross section at 8 TeV using CMS data, confirming Standard Model predictions and setting new limits on anomalous gauge couplings.

Contribution

First measurement of the Z gamma to neutrino-antineutrino gamma cross section at 8 TeV, with results aligning with the Standard Model and improved limits on anomalous couplings.

Findings

Measured cross section: 52.7 fb with uncertainties.

Results agree with Standard Model prediction of 50.0 fb.

Set the most stringent limits on anomalous gauge couplings.

Abstract

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.