Observation of the Z???+?? Decay in pp Collisions at ?s=13??TeV
Yükleniyor...
Tarih
2018
Yazarlar
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
American Physical Society
Erişim Hakkı
Özet
This Letter presents the observation of the rare Z boson decay Z???+??. Here, ? represents contributions from direct J/? and ?(2S)?J/?X, ?+?? is a pair of electrons or muons, and the J/?meson is detected via its decay to ?+??. The sample of proton-proton collision data, collected by the CMS experiment at the LHC at a center-of-mass energy of 13 TeV, corresponds to an integrated luminosity of 35.9??fb?1. The signal is observed with a significance in excess of 5 standard deviations. After subtraction of the ?(2S)?J/?X contribution, the ratio of the branching fraction of the exclusive decay Z?J/??+?? to the decay Z??+???+?? within a fiducial phase space is measured to be B(Z?J/??+??)/B(Z??+???+??)=0.67±0.18(stat)±0.05(syst).
Açıklama
Anahtar Kelimeler
Rare decays, LEPTONS, W & Z bosons, Hadron colliders, QUARKONİA
Kaynak
WoS Q Değeri
Q1
Scopus Q Değeri
Q1
Cilt
Sayı
Künye
PHYSICAL REVIEW LETTERS 121, 141801 (2018)
