Phases of Hadron-Quark Matter in (Proto) Neutron Stars
Fridolin Weber,
Delaney Farrell,
William M. Spinella,
Germán Malfatti,
Milva G. Orsaria,
Gustavo A. Contrera,
Ian Maloney
Affiliations
Fridolin Weber
Department of Physics, San Diego State University, San Diego, CA 92182, USA
Delaney Farrell
Department of Physics, San Diego State University, San Diego, CA 92182, USA
William M. Spinella
Department of Sciences, Wentworth Institute of Technology, 550 Huntington Avenue, Boston, MA 02115, USA
Germán Malfatti
Grupo de Gravitación, Astrofísica y Cosmología, Facultad de Ciencias Astronómicas y Geofísicas, Universidad Nacional de La Plata, Paseo del Bosque S/N, La Plata 1900, Argentina
Milva G. Orsaria
Grupo de Gravitación, Astrofísica y Cosmología, Facultad de Ciencias Astronómicas y Geofísicas, Universidad Nacional de La Plata, Paseo del Bosque S/N, La Plata 1900, Argentina
Gustavo A. Contrera
Grupo de Gravitación, Astrofísica y Cosmología, Facultad de Ciencias Astronómicas y Geofísicas, Universidad Nacional de La Plata, Paseo del Bosque S/N, La Plata 1900, Argentina
Ian Maloney
Department of Physics, San Diego State University, San Diego, CA 92182, USA
In the first part of this paper, we investigate the possible existence of a structured hadron-quark mixed phase in the cores of neutron stars. This phase, referred to as the hadron-quark pasta phase, consists of spherical blob, rod, and slab rare phase geometries. Particular emphasis is given to modeling the size of this phase in rotating neutron stars. We use the relativistic mean-field theory to model hadronic matter and the non-local three-flavor Nambu−Jona-Lasinio model to describe quark matter. Based on these models, the hadron-quark pasta phase exists only in very massive neutron stars, whose rotational frequencies are less than around 300 Hz. All other stars are not dense enough to trigger quark deconfinement in their cores. Part two of the paper deals with the quark-hadron composition of hot (proto) neutron star matter. To this end we use a local three-flavor Polyakov−Nambu−Jona-Lasinio model which includes the ’t Hooft (quark flavor mixing) term. It is found that this term leads to non-negligible changes in the particle composition of (proto) neutron stars made of hadron-quark matter.
