Pasta structures in compact stars

TL;DR

This paper reviews the formation and properties of pasta structures in dense matter within compact stars, highlighting the role of Coulomb effects and phase transitions at various densities.

Contribution

It provides a comprehensive review of pasta structures across different phase transitions, emphasizing the importance of Coulomb potential treatment and charge screening effects.

Findings

Charge screening significantly affects pasta structure density ranges.

A consistent Coulomb and particle density treatment recovers the Maxwell construction.

Pasta structures occur at multiple density regimes during phase transitions.

Abstract

We review our recent works about ``pasta'' structures following the first-order phase transition in dense matter, which correspond to the structured mixed phases with geometrical symmetries. Three kinds of phase transitions at different density ranges are examined as the stages of pasta structures: liquid-gas phase transition at subnuclear density, kaon condensation and hadron-quark phase transition at high density. Charge density as well as particle density is non-uniform there. A consistent treatment of the Coulomb potential and the particle densities is presented and a peculiar role of the Coulomb potential is elucidated: the physical picture of the Maxwell construction will be effectively recovered. It largely influences the density regime of pasta structures by the charge screening effect.