QCD sum rules for the Δ isobar in neutron matter

L. Jesuel Marques, Su Houng Lee, Aaron Park, R. D. Matheus, Kie Sang Jeong

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

We study the properties of the Δ isobar in the symmetric and asymmetric nuclear matter using the QCD sum rules approach based on the energy dispersion relation. Allowing for different continuum thresholds for the polarization tensors with different dimensions, we find stable masses for the Δ in both the vacuum and the medium. Compared to the nucleon case, we find that the vector repulsion is smaller for the Δ while the scalar attraction is similar (75 MeV vector repulsion and 200 MeV scalar attraction in the symmetric matter). The smaller vector repulsion can be understood using the Pauli principle and a constituent quark model. Also, the isospin dependence of the quasiparticle energy, which mainly comes from the vector self-energy, is quite weak. We also allow for an explicit π-N continuum contribution to the polarization function but find its effect to be minimal. Phenomenological consequences of our results are discussed.

Original languageEnglish
Article number025206
JournalPhysical Review C
Volume98
Issue number2
DOIs
Publication statusPublished - 2018 Aug 22

    Fingerprint

All Science Journal Classification (ASJC) codes

  • Nuclear and High Energy Physics

Cite this

Jesuel Marques, L., Lee, S. H., Park, A., Matheus, R. D., & Jeong, K. S. (2018). QCD sum rules for the Δ isobar in neutron matter. Physical Review C, 98(2), [025206]. https://doi.org/10.1103/PhysRevC.98.025206