We investigate the dynamical evolution of a star cluster in an external tidal field by using N-body simulations, with focus on the effects of the presence or absence of neutron star natal velocity kicks. We show that, even if neutron stars typically represent less than 2 per cent of the total bound mass of a star cluster, their primordial kinematic properties may affect the lifetime of the system by up to almost a factor of 4. We interpret this result in the light of two known modes of star cluster dissolution, dominated by either early stellar evolution mass-loss or two-body relaxation. The competition between these effects shapes the mass-loss profile of star clusters, which may either dissolve abruptly (`jumping’), in the pre-core-collapse phase, or gradually (`skiing’), after having reached core collapse.
For details, have a look at the MNRAS Letter.
This project has been conducted by Filippo Contenta, a PhD student at University of Surrey, who, during the 2014 ISIMA program, has worked under the supervision of Douglas Heggie and myself.
Our research has been highlighted in a few press releases, mainly in United Kingdom and Italy:
Ski or jump? How neutron stars kicks can break up clusters
RAS – Royal Astronomical Society
NAM – National Astronomy Meeting 2015 (where Filippo has presented this result)
Come ti dissolvo un ammasso globulare
INAF – Instituto Nazionale di Astrofisica (in Italian)
AllNews24 (in Italian)
Comments are closed.