TY - JOUR

T1 - The relativistic two-nucleon problem in nuclear matter

AU - Horowitz, C. J.

AU - Serot, Brian D.

PY - 1987/3/23

Y1 - 1987/3/23

N2 - A new covariant formalism is developed for studying two-baryon correlations in infinite nuclear matter. The formalism is based on renormalizable, relativistic quantum field theories of mesons and baryons (quantum hadrodynamics) and involves a self-consistent summation of the relativistic ladder diagrams using a quasipotential approximation. Self-consistency modifies both the singleparticle spectrum and wave functions and introduces important density dependence into matrix elements of the one-boson-exchange (ladder) interaction. Results are obtained for the Walecka model, which describes the nucleon-nucleon interaction through neutral scalar and vector meson exchange. The mean-field theory (MFT) values of the large scalar and vector components of the baryon self-energy ("single-particle potential") are modified only slightly by correlations, yielding a baryon effective mass M* that decreases rapidly with increasing density. Moreover, correlations have a small effect on the high-density nuclear equation of state, which is quite stiff due to the small value of M* and is given accurately by the MFT. In contrast, due to cancellations near equilibrium density, correlations produce significant corrections to the MFT binding energy. Calculated saturation properties are sensitive to the choice of quasipotential and the introduction of meson-baryon form factors. Finally, modifications from the shifted baryon mass in negative-energy states are included in a mean-field approximation. These corrections are significant in calculations of the binding energy.

AB - A new covariant formalism is developed for studying two-baryon correlations in infinite nuclear matter. The formalism is based on renormalizable, relativistic quantum field theories of mesons and baryons (quantum hadrodynamics) and involves a self-consistent summation of the relativistic ladder diagrams using a quasipotential approximation. Self-consistency modifies both the singleparticle spectrum and wave functions and introduces important density dependence into matrix elements of the one-boson-exchange (ladder) interaction. Results are obtained for the Walecka model, which describes the nucleon-nucleon interaction through neutral scalar and vector meson exchange. The mean-field theory (MFT) values of the large scalar and vector components of the baryon self-energy ("single-particle potential") are modified only slightly by correlations, yielding a baryon effective mass M* that decreases rapidly with increasing density. Moreover, correlations have a small effect on the high-density nuclear equation of state, which is quite stiff due to the small value of M* and is given accurately by the MFT. In contrast, due to cancellations near equilibrium density, correlations produce significant corrections to the MFT binding energy. Calculated saturation properties are sensitive to the choice of quasipotential and the introduction of meson-baryon form factors. Finally, modifications from the shifted baryon mass in negative-energy states are included in a mean-field approximation. These corrections are significant in calculations of the binding energy.

UR - http://www.scopus.com/inward/record.url?scp=0000193548&partnerID=8YFLogxK

U2 - 10.1016/0375-9474(87)90370-8

DO - 10.1016/0375-9474(87)90370-8

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AN - SCOPUS:0000193548

SN - 0375-9474

VL - 464

SP - 613

EP - 699

JO - Nuclear Physics A

JF - Nuclear Physics A

IS - 4

ER -