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arXiv · hep-ph/9411265

QCD sum rules for $Δ$ isobar in nuclear matter

Xuemin Jin
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Abstract

The self-energies of $Δ$ isobar propagating in nuclear matter are calculated using the finite-density QCD sum-rule methods. The calculations show that the Lorentz vector self-energy for the $Δ$ is significantly smaller than the nucleon vector self-energy. The magnitude of the $Δ$ scalar self-energy is larger than the corresponding value for the nucleon, which suggests a strong attractive net self-energy for the $Δ$; however, the prediction for the scalar self-energy is very sensitive to the density dependence of certain in-medium four-quark condensate. Phenomenological implications for the couplings of the $Δ$ to the nuclear scalar and vector fields are briefly discussed.

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Xuemin Jin. 1994-11-10. QCD sum rules for $Δ$ isobar in nuclear matter. https://doi.org/10.1103/physrevc.51.2260

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