Bibcode
Khachatryan, V.; Sirunyan, A. M.; Tumasyan, A.; Adam, W.; Asilar, E.; Bergauer, T.; Brandstetter, J.; Brondolin, E.; Dragicevic, M.; Erö, J.; Flechl, M.; Friedl, M.; Frühwirth, R.; Ghete, V. M.; Hartl, C.; Hörmann, N.; Hrubec, J.; Jeitler, M.; Knünz, V.; König, A.; Krammer, M.; Krätschmer, I.; Liko, D.; Matsushita, T.; Mikulec, I.; Rabady, D.; Rahbaran, B.; Rohringer, H.; Schieck, J.; Schöfbeck, R.; Strauss, J.; Treberer-Treberspurg, W.; Waltenberger, W.; Wulz, C.-E.; Mossolov, V.; Shumeiko, N.; Suarez Gonzalez, J.; Alderweireldt, S.; Cornelis, T.; de Wolf, E. A.; Janssen, X.; Knutsson, A.; Lauwers, J.; Luyckx, S.; Rougny, R.; van de Klundert, M.; van Haevermaet, H.; van Mechelen, P.; van Remortel, N.; van Spilbeeck, A.; Abu Zeid, S.; Blekman, F.; D'Hondt, J.; Daci, N.; de Bruyn, I.; Deroover, K.; Heracleous, N.; Keaveney, J.; Lowette, S.; Moreels, L.; Olbrechts, A.; Python, Q.; Strom, D.; Tavernier, S.; van Doninck, W.; van Mulders, P.; van Onsem, G. P.; van Parijs, I.; Barria, P.; Brun, H.; Caillol, C.; Clerbaux, B.; de Lentdecker, G.; Fasanella, G.; Favart, L.; Grebenyuk, A.; Karapostoli, G.; Lenzi, T.; Léonard, A.; Maerschalk, T.; Marinov, A.; Perniè, L.; Randle-Conde, A.; Reis, T.; Seva, T.; Vander Velde, C.; Vanlaer, P.; Yonamine, R.; Zenoni, F.; Zhang, F.; Beernaert, K.; Benucci, L.; Cimmino, A.; Crucy, S.; Dobur, D.; Fagot, A.; Garcia, G.; Gul, M.; McCartin, J.; Ocampo Rios, A. A. et al.
Bibliographical reference
Journal of High Energy Physics, Volume 2016, article id.125, 54 pp.
Advertised on:
3
2016
Citations
31
Refereed citations
22
Description
A search for compositeness of electrons and muons is presented using a
data sample of proton-proton collisions at a center-of-mass energy of
sqrt{s} = 8 TeV collected with the CMS detector at the LHC and
corresponding to an integrated luminosity of 19.7 fb-1.
Excited leptons (ℓ *) produced via contact interactions
in conjunction with a standard model lepton are considered, and a search
is made for their gauge decay modes. The decays considered are ℓ
* → ℓγ and ℓ * → ℓZ,
which give final states of two leptons and a photon or, depending on the
Z-boson decay mode, four leptons or two leptons and two jets. The number
of events observed in data is consistent with the standard model
prediction. Exclusion limits are set on the excited lepton mass, and the
compositeness scale Λ. For the case M ℓ* =
Λ the existence of excited electrons (muons) is excluded up to
masses of 2.45 (2.47) TeV at 95% confidence level. Neutral current
decays of excited leptons are considered for the first time, and limits
are extended to include the possibility that the weight factors f and
f', which determine the couplings between standard model leptons and
excited leptons via gauge mediated interactions, have opposite sign.
[Figure not available: see fulltext.]