# Darmstadt 2016 – wissenschaftliches Programm

## Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

# HK: Fachverband Physik der Hadronen und Kerne

## HK 67: Nuclear Astrophysics VI

### HK 67.6: Vortrag

### Freitag, 18. März 2016, 15:30–15:45, S1/01 A02

**Equation of state of neutron-rich nuclear matter from chiral effective field theory** — Norbert Kaiser and •Susanne Strohmeier — Technische Universität München

Based on chiral effective field theory, the equation of state of neutron-rich nuclear matter is investigated systematically. The contributing diagrams include one- and two-pion exchange together with three-body terms arising from virtual Δ(1232)-isobar excitations. The proper expansion of the energy per particle, Ē(*k*_{f},δ) = Ē_{n}(*k*_{f}) + δ *B*_{1}(*k*_{f}) +δ^{5/3} *B*_{5/3} (*k*_{f}) + δ ^{2} *B*_{2} (*k*_{f}) + … , for the system with neutron density ρ_{n}= *k*_{f}^{3} (1−δ)/3 π^{2} and proton density ρ_{p}= *k*_{f}^{3} δ/3 π^{2} is performed analytically for the various interaction contributions. One observes essential structural differences to the commonly used quadratic approximation. The density dependent coefficient *B*_{1}(*k*_{f}) turns out to be unrelated to the isospin-asymmetry of nuclear matter. The coefficient *B*_{5/3} (*k*_{f}) of the non-analytical δ^{5/3}-term receives contributions from the proton kinetic energy and from the one- and two-pion exchange interactions. The physical consequences for neutron star matter are studied.