CMS-PAS-SMP-12-020

CMS-PAS-SMP-12-020
Study of the Zgamma production in gamma+MET final state at sqrt{s} = 7 TeV
CMS Collaboration
2013

Abstract: The first measurement of the ${\rm Z}\gamma\to\nu\bar{\nu}\gamma$ cross section in pp collisions at $\sqrt{s} = 7$ ~TeV is presented, using data corresponding to an integrated luminosity of 5 fb $^{-1}$ collected with the CMS detector.The measurement is based on the observation of events with an imbalance of the transverse energy in excess of 130 GeV and a single photon candidate in the absolute pseudorapidity range $\|\eta\| < 1.4$ and with the transverse energy above 145 GeV. The Z $\gamma\to\nu\bar{\nu}\gamma$ production cross section is measured to be .3 \pm 4.2 ({\rm stat.}) \pm 4.3 ({\rm syst.}) \pm 0.5 ({\rm lumi.}) $fb, which is in good agreement with the theoretical prediction of .9 \pm 1.1$ fb in the standard model. In addition, the most stringent limits to date are established on the anomalous ${\rm Z}{\rm Z}\gamma$ and ${\rm Z}\gamma\gamma$ trilinear gauge boson couplings.
Links: CDS record (PDF) ; inSPIRE record ; Public twiki page ; CADI line (restricted) ; Figures are available from the CDS record. These preliminary results are superseded in this paper, JHEP 10 (2013) 164.

Compact Muon Solenoid
LHC, CERN