Measurement of the cross section for electroweak production of a Z boson, a photon and two jets in proton-proton collisions at root s=13TeV and constraints on anomalous quartic couplings


Sirunyan A. M., Tumasyan A., Adam W., Ambrogi F., Bergauer T., Brandstetter J., ...More

JOURNAL OF HIGH ENERGY PHYSICS, no.6, 2020 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: Issue: 6
  • Publication Date: 2020
  • Doi Number: 10.1007/jhep06(2020)076
  • Journal Name: JOURNAL OF HIGH ENERGY PHYSICS
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, INSPEC, zbMATH, Directory of Open Access Journals
  • Çukurova University Affiliated: Yes

Abstract

A measurement is presented of the cross section for electroweak production of a Z boson and a photon in association with two jets (Z gamma jj) in proton-proton collisions. The Z boson candidates are selected through their decay into a pair of electrons or muons. The process of interest, electroweak Z gamma jj production, is isolated by selecting events with a large dijet mass and a large pseudorapidity gap between the two jets. The measurement is based on data collected at the CMS experiment at root s = 13 TeV, corresponding to an integrated luminosity of 35.9 fb(-1). The observed significance of the signal is 3.9 standard deviations, where a significance of 5.2 standard deviations is expected in the standard model. These results are combined with published results by CMS at root s = 8 TeV, which leads to observed and expected respective significances of 4.7 and 5.5 standard deviations. From the 13 TeV data, a value is obtained for the signal strength of electroweak Z gamma jj production and bounds are given on quartic vector boson interactions in the framework of dimension-eight effective field theory operators.