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Pentaquarks $uudd\bar q$ with One Color Sextet Diquark

C. Semay·F. Brau·B. Silvestre-Brac
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Abstract

The masses of pentaquarks $uudd\bar s$ are calculated within the framework of a semirelativistic effective QCD Hamiltonian, using a diquark picture. This approximation allows a correct treatment of the confinement, assumed here to be similar to a Y-junction. With only color antitriplet diquarks, the mass of the pentaquark candidate $Θ$ with positive parity is found around 2.2 GeV. It is shown that, if a color sextet diquark is present, the lowest $uudd\bar s$ pentaquark is characterized by a much smaller mass with a negative parity. A mass below 1.7 GeV is computed, if the masses of the color antitriplet and color sextet diquarks are taken similar.

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C. Semay, F. Brau, B. Silvestre-Brac. 2005-02-21. Pentaquarks $uudd\bar q$ with One Color Sextet Diquark. https://doi.org/10.1103/physrevlett.94.062001

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