A search for flavor violating decays of the Z boson to charged leptons is performed using data from proton-proton collisions at root s = 13 TeV collected with the CMS detector at the LHC, corresponding to an integrated luminosity of 138 fb(-1). Each of the decays Z -> e mu, Z -> e tau, and Z -> mu tau is considered. The data are consistent with the backgrounds expected from standard model processes. For the Z -> e mu channel the observed (expected) 95% confidence level upper limit on the branching fraction is 1.9(2.0) x 10(-7), which is the most stringent direct limit to date on this process; the corresponding limits for the Z -> e tau and Z -> mu tau channels are 13.8(11.4) x 10(-6) and 12.0(5.3) x 10(-6), respectively. Additionally, the e mu final state is used to search for lepton flavor violating decays of Z' resonances in the mass range from 110 to 500 GeV. No significant excess is observed above the predicted background levels.

Search for charged lepton flavor violating Z and Z' boson decays in proton-proton collisions at √s=13 TeV

Bianchini, L.;Cipriani, M.;Donato, S.;Marini, A. C.;Messineo, A.;Rizzi, A.;Tonelli, G.;
2025-01-01

Abstract

A search for flavor violating decays of the Z boson to charged leptons is performed using data from proton-proton collisions at root s = 13 TeV collected with the CMS detector at the LHC, corresponding to an integrated luminosity of 138 fb(-1). Each of the decays Z -> e mu, Z -> e tau, and Z -> mu tau is considered. The data are consistent with the backgrounds expected from standard model processes. For the Z -> e mu channel the observed (expected) 95% confidence level upper limit on the branching fraction is 1.9(2.0) x 10(-7), which is the most stringent direct limit to date on this process; the corresponding limits for the Z -> e tau and Z -> mu tau channels are 13.8(11.4) x 10(-6) and 12.0(5.3) x 10(-6), respectively. Additionally, the e mu final state is used to search for lepton flavor violating decays of Z' resonances in the mass range from 110 to 500 GeV. No significant excess is observed above the predicted background levels.
2025
Hayrapetyan, A.; Makarenko, V.; Tumasyan, A.; Adam, W.; Andrejkovic, J. W.; Benato, L.; Bergauer, T.; Dragicevic, M.; Giordano, C.; Hussain, P. S.; Je...espandi
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11568/1357931
 Attenzione

Attenzione! I dati visualizzati non sono stati sottoposti a validazione da parte dell'ateneo

Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus ND
  • ???jsp.display-item.citation.isi??? 0
social impact