Anisotropic lattice QCD study of pentaquark baryons in spin 3/2 channel
نویسندگان
چکیده
We perform the comprehensive analysis of the pentaquark (5Q) in JP = 3/2± channel using anisotropic quenched lattice QCD. We employ the standard Wilson gauge action at β = 5.75 and the O(a) improved Wilson (clover) quark action on a 123 ×96 lattice with the renormalized anisotropy as as/at = 4. A large number of gauge configurations as Nconf = 1000 is analyzed, which is found to be essential to achieve a reliable measurement. We study three types of the Rarita-Schwinger intepolationg fields with I = 0: (a) the NK∗-type, (b) the (color-)twisted NK∗type, (c) a diquark-type. As a result, we find only massive states as m5Q ≃ 2.1− 2.2 GeV in JP = 3/2− channel, and m5Q = 2.4− 2.6 GeV in JP = 3/2+ channel in the chiral limit. The analysis with the hybrid boundary condition (HBC) is performed to distinguish whether these resonances are compact 5Q resonances or two-particle scattering states. No low-lying compact 5Q resonance states are found below 2.1GeV.
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