First observation of the doubly charmed baryon Xi(+)(cc).
We observe a signal for the doubly charmed baryon Xi(+)(cc) in the charged decay mode Xi(+)(cc)-->Lambda(+)(c)K-pi(+) in data from SELEX, the charm hadroproduction experiment at Fermilab. We observe an excess of 15.9 events over an expected background of 6.1+/-0.5 events, a statistical significance of 6.3sigma. The observed mass of this state is 3519+/-1 MeV/c(2). The Gaussian mass width of this state is 3 MeV/c(2), consistent with resolution; its lifetime is less than 33 fs at 90% confidence.
Mattson
M
M
Carnegie-Mellon University, Pittsburgh, Pennsylvania 15213, USA.
Alkhazov
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Atamantchouk
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Balatz
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Bondar
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Cooper
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Dauwe
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Davidenko
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Dersch
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Dolgolenko
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Dzyubenko
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Edelstein
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Emediato
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Endler
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Engelfried
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Eschrich
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Escobar
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Evdokimov
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Filimonov
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Garcia
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Gaspero
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Giller
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Golovtsov
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Gouffon
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Gülmez
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Kangling
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Iori
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Jun
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Kaya
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Kilmer
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Kim
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Kochenda
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Konorov
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Kozhevnikov
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Krivshich
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Krüger
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Kubantsev
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Kubarovsky
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Kulyavtsev
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Kuropatkin
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Kurshetsov
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Kushnirenko
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Kwan
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Lach
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Lamberto
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Landsberg
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Larin
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Leikin
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Yunshan
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Luksys
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Lungov
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Maleev
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Mao
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Chensheng
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Zhenlin
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Mathew
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McCliment
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Moinester
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Morelos
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Nelson
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Newsom
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Nilov
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Nurushev
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Ocherashvili
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Oliveira
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Onel
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Ozel
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Ozkorucuklu
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Penzo
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Petrenko
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Procario
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Prutskoi
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Ramberg
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Rappazzo
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Razmyslovich
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Russ
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Schiavon
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Simon
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Sitnikov
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Smith
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Srivastava
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Steiner
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Stepanov
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Stutte
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Svoiski
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Terentyev
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Thomas
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Uvarov
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Vasiliev
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Vavilov
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Verebryusov
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Victorov
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Vishnyakov
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Vorobyov
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Vorwalter
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You
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Wenheng
Zhao
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Shuchen
Zheng
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Zukanovich-Funchal
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