Critical phenomena in neutron stars: II. Headon collisions
Abstract
We consider the headon collision of equalmass neutron stars boosted towards each other and we study the behaviour of such systems near the threshold of blackhole formation. In particular, we confirm the previous findings by Jin K J et al (2007 Phys. Rev. Lett 98 131101) that a type I critical phenomenon can be observed by finetuning the initial mass of the two neutron stars. At the same time, we argue against the interpretation that the critical solution is not a perturbed spherical star and show instead that the metastable star corresponds to a (perturbed) equilibrium solution on the unstable branch of the equilibrium configurations. As a result, the headon collision of two neutron stars near the critical threshold can be seen as a transition in the space of configurations from an initial stable solution over to a critical metastable one which can either migrate to a stable solution or collapse to a black hole. The critical exponent for this process shows a fine structure which was already observed in the case of the critical collapse of scalar fields but never before for perfect fluids.
 Publication:

Classical and Quantum Gravity
 Pub Date:
 December 2010
 DOI:
 10.1088/02649381/27/23/235016
 arXiv:
 arXiv:1007.2797
 Bibcode:
 2010CQGra..27w5016K
 Keywords:

 General Relativity and Quantum Cosmology;
 Mathematical Physics
 EPrint:
 15 pages, 19 figures