Here is a list of links/insitution/collaboartions on the study of neutron stars:

• Arcetri High Energy Group. The High Energy Astrophysics Group at the Osservatorio di Arcetri INAF
  
  
• Arcetri Space & Astrophysical Plasmas at the Physics & Astronomy Department of the Firenze University
  
  
• NewCOMPSTAR: "This COST Action brings together the leading experts in astrophysics, nuclear physics and gravitational physics to address this fascinating but challenging research area through an interdisciplinary approach."
  
  
• Astrophysics@ITP. Group working on compact stars and physics of dense matter, gravitational physics and general relativity, astroparticle physics, and cosmology
  
  
• INFN - TeOnGrav: "This INFN initiative led by Dr. Leonardo Gualtieri (Roma, La Sapienza) focus on the study of sources of gravitational waves."
  
  
• Theoretical and computational physics, at the Iniversity of Trento
  
  
• Gravitational Wave Group at the Sapienza, University of Rome
  
  
• Gravitational Physics Group at the University of Parma
  
  
• Gruppo 4 - Fisica Teorica University of Ferrara