Observation of eta'c production in gammagamma fusion at CLEO.
We report on the observation of the eta(')(c)(2(1)S0), the radial excitation of the eta(c)(1(1)S0) ground state of charmonium, in the two-photon fusion reaction gammagamma-->eta(')(c)-->K(0)(S)K+/-pi(-/+) in 13.6 fb(-1) of CLEO II/II.V data and 13.1 fb(-1) of CLEO III data. We obtain M(eta(')(c))=3642.9+/-3.1(stat)+/-1.5(syst) MeV and M(eta(c))=2981.8+/-1.3(stat)+/-1.5(syst) MeV. The corresponding values of hyperfine splittings between 1S0 and 3S1 states are DeltaM(hf)(1S)=115.1+/-2.0 MeV and DeltaM(hf)(2S)=43.1+/-3.4 MeV. Assuming that the eta(c) and eta(')(c) have equal branching fractions to K(S)Kpi, we obtain Gamma(gammagamma)(eta(')(c))=1.3+/-0.6 keV.
Asner
D M
DM
University of Pittsburgh, Pittsburgh, Pennsylvania 15260, USA.
Dytman
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Mehrabyan
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Mueller
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Nam
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Savinov
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Huang
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Miller
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Pavlunin
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Shibata
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Shipsey
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Adams
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Chasse
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Cummings
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Danko
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Napolitano
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Cronin-Hennessy
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Park
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Park
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Thayer
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Thorndike
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Coan
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Gao
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Liu
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Stroynowski
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Artuso
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Boulahouache
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Blusk
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Butt
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Dambasuren
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Dorjkhaidav
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Haynes
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Menaa
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Mountain
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Muramatsu
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Nandakumar
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Redjimi
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Sia
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Skwarnicki
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Stone
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Wang
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Zhang
Kevin
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Mahmood
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Csorna
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Bonvicini
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Cinabro
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Dubrovin
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Bornheim
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Lipeles
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Shapiro
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Weinstein
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Mahapatra
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Nelson
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Ferguson
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Tatishvili
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Vogel
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Watkins
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Adam
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Alexander
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Berkelman
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Boisvert
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Cassel
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Duboscq
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Ecklund
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Ehrlich
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Galik
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Gibbons
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Gittelman
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Gray
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Hartill
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Heltsley
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Hsu
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Jones
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Kandaswamy
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Kreinick
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Kuznetsov
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Magerkurth
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Mahlke-Krüger
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Meyer
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Patterson
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Pedlar
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Peterson
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Pivarski
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Riley
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Sadoff
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Schwarthoff
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Shepherd
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Sun
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Thayer
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Urner
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Wilksen
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Weinberger
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Athar
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Avery
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Breva-Newell
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Potlia
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Stoeck
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Yelton
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Eisenstein
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Gollin
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Karliner
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Lowrey
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Naik
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Sedlack
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Selen
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Thaler
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Williams
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Edwards
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Besson
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Gao
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Gong
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Kubota
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Li
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Poling
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Scott
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Smith
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Stepaniak
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Urheim
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Metreveli
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Seth
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Tomaradze
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Zweber
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Arms
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Eckhart
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Gan
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Gwon
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Severini
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Skubic
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