https://doi.org/10.1051/epjconf/20100306003
Chiral effective field theory for nuclear matter including long- and short-range multi-nucleon interactions
1
Helmholtz-Institut für Strahlen- und Kernphysik (Theorie) and
Bethe Center for Theoretical Physics, Universität Bonn,
D-53115
Bonn,
Germany
2
Departamento de Física, Universidad de Murcia,
E-30071
Murcia,
Spain
3
Institut für Kernphysik, Institute for Advanced Simulation and
Jülich Center for Hadron Physics, Forschungszentrum
Jülich, D-52425
Jülich,
Germany
a e-mail: lacour@hiskp.uni-bonn.de
We review on a novel chiral power counting scheme for in-medium chiral perturbation theory with nucleons and pions as degrees of freedom. It allows for a systematic expansion taking into account local as well as pion-mediated inter-nucleon interactions. Based on this power counting, one can identify classes of nonperturbative diagrams that require a resummation. As a method for performing those resummations we review on the techniques of Unitary Chiral Pertubation Theory for nucleon-nucleon interactions. We then apply both power counting and non-perturbative methods to the example of calculating the pion self-energy in asymmetric nuclear matter up-to-and-including next-to-leading order. It is shown that the leading corrections involving in-medium nucleon-nucleon interactions cancel between each other at given chiral orders.
© Owned by the authors, published by EDP Sciences, 2010
