Observation of a Narrow Resonance Formed in e+ e- Annihilation at 9.46-GeV

An experiment using the PLUTO detector has observed the formation of a narrow, high mass, resonance in e + e − annihilations at the DORIS storage ring. The mass is determined to be 9.46±0.01 GeV which is consistent with that of the Upsilon. The gaussian width σ is observed as 8±1 MeV and is equal to the DORIS energy resolution. This suggests that the resonance is a bound state of a new heavy quark-antiquark pair. An electronic width Γ ee =1.3±0.4 keV was obtained. In standard theoretical models, this favors a quark charge assignment of 1 3 .

upsilon mesons: history
electron positron: colliding beams
electron positron: annihilation
hadron: electroproduction
cross section: hadronic
energy dependence
Upsilon(9460): electroproduction
Upsilon(9460): mass
Upsilon(9460): leptonic decay
Upsilon(9460): width

References(4)

Figures(0)

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The Total Hadronic Cross-Section for e+ e- Annihilation Between 3.1-GeV and 4.8-GeV Center-Of-Mass Energy

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