Search for the Theta+ Pentaquark in the gammad--> DeltanK+ reaction measured with the CLAS spectrometer.
For the first time, the reaction gammad-->DeltanK+ has been analyzed in order to search for the exotic pentaquark baryon Theta+(1540). The data were taken at Jefferson Laboratory, using the Hall-B tagged-photon beam of energy between 0.8 and 3.6 GeV and the CEBAF Large Acceptance Spectrometer (CLAS). No statistically significant structures were observed in the nK+ invariant-mass distribution. The upper limit on the gammad-->DeltaTheta+ integrated cross section has been calculated and found to be between 5 and 25 nb, depending on the production model assumed. The upper limit on the differential cross section is also reported.
Niccolai
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Institut de Physique Nucléaire, Orsay, France.
Mirazita
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Rossi
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Baltzell
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Carman
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McKinnon
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Mibe
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Stepanyan
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Tedeschi
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Adams
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Ambrozewicz
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Anefalos Pereira
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Asryan
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Avakian
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Bagdasaryan
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Batourine
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Battaglieri
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Bedlinskiy
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Bektasoglu
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Bellis
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Benmouna
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Berman
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Biselli
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Boiarinov
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Bouchigny
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Bradford
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Branford
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Briscoe
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Brooks
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Bültmann
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Burkert
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Butuceanu
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Calarco
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Careccia
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Carnahan
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Chen
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Cole
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Collins
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Coltharp
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Crabb
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Crannell
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Crede
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Cummings
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Dashyan
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Degtyarenko
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De Masi
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Deppman
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De Sanctis
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Deur
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Dharmawardane
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Donnelly
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Doughty
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Dugger
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Dzyubak
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Egiyan
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Egiyan
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Elouadrhiri
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Eugenio
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Fedotov
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Feldman
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Funsten
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Gyurjyan
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Hadjidakis
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Hakobyan
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Hardie
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Hersman
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Holtrop
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Hyde-Wright
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Ilieva
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Ireland
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Ishkhanov
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Isupov
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Ito
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Jenkins
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Jo
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Joo
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Juengst
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Kellie
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Khandaker
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Kim
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Klein
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Klein
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Klimenko
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Kramer
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Kubarovsky
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Kuhn
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Kuleshov
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Lachniet
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Langheinrich
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Lawrence
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Livingston
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MacCormick
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Markov
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Niroula
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Nozar
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de Oliveira Echeimberg
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Osipenko
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Ostrovidov
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Park
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Pasyuk
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Paterson
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Pierce
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Pogorelko
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Pozdniakov
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Preedom
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Raue
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Rosner
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Schumacher
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Serov
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Shvedunov
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Smith
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Stavinsky
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Stepanyan
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Stokes
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Stoler
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Strakovsky
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Strauch
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Wolin
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Zhang
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Zhao
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