The zoo of isolated neutron stars

TL;DR

This paper reviews the diverse observational properties and recent discoveries of various classes of isolated neutron stars, highlighting their unique behaviors and the theoretical models that explain their underlying physics.

Contribution

It provides a comprehensive overview of the different types of isolated neutron stars, summarizing recent observational findings and theoretical advancements in understanding their physics.

Findings

Diverse behaviors observed in different neutron star classes

Recent discoveries have expanded understanding of neutron star properties

Theoretical models have advanced insights into neutron star physics

Abstract

Discovered over fifty years ago, neutron stars exhibit a remarkable variety of behaviors depending on their age, magnetic field strength, rotational dynamics, emission mechanisms, and surrounding environments. This diversity in their observational manifestations has led astronomers to classify neutron stars into numerous categories, much like wandering through a zoo and admiring various species. This chapter focuses on isolated (i.e., non-accreting) neutron stars. We review extensive observational results of rotation-powered pulsars, magnetars, X-ray dim isolated neutron stars and central compact objects, highlighting the unique properties and recent discoveries of these neutron star classes. We briefly touch on theoretical models that have significantly advanced our understanding of these classes, emphasizing the valuable insights they provide into the underlying physics of neutron stars.