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A QCD Sum Rule Study of $Θ^+$ in Nuclear Matter

F. S. Navarra·M. Nielsen·K. Tsushima
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Abstract

We consider a $[ud]^2\bar{s}$ current, in the finite-density QCD sum rule approach, to investigate the scalar and vector self-energies of the recently observed pentaquark state $Θ^+(1540)$, propagating in nuclear mater. We find that, opposite to what was obtained for the nucleon, the vector self-energy is negative, and the scalar self-energy is positive. There is a substantial cancellation between them resulting in an attractive net self-energy of the same order as in the nucleon case.

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F. S. Navarra, M. Nielsen, K. Tsushima. 2004-12-06. A QCD Sum Rule Study of $Θ^+$ in Nuclear Matter. https://doi.org/10.1016/j.physletb.2004.12.016

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