On the Formation of PSR J1640+2224: A Neutron Star Born Massive?

Dynamics of Psr J0045-7319/b-star Binary and Neutron Star Formation

One of the fundamental questions in the studies of pulsars concerns the physical conditions of neutron star at birth. Of particular interest is the initial spin periods and velocities of pulsars, as they are related to such issues as supernova explosion mechanism and gravitational wave emission from core collapse. The PSR J0045-7319 binary (containing a 0.93 s radio pulsar and a massive B-star ...

Double Neutron Star Formation

We present results of a population synthesis study aimed at examining the role of spin-kick alignment in producing a correlation between the spin period of the first-born neutron star and the orbital eccentricity of observed double neutron star binaries in the Galactic disk. We find spin-kick alignment to be compatible with the observed correlation, but not to alleviate the requirements for low...

Massive Star Formation

Dynamical Constraints on Massive Star Formation

Extragalactic HII regions and their ionizing star clusters are the most prominent signposts of recent starbirth activity in galaxies. In this paper, we present optical measurements of nearby extragalactic HII regions with the aim of investigating possible relationships between the newborn ionizing clusters and their dynamical environment. Evidence for variations in the measured HII region prope...

Massive Star and Star Cluster Formation

I review the status of massive star formation theories: accretion from collapsing, massive, turbulent cores; competitive accretion; and stellar collisions. I conclude the observational and theoretical evidence favors the first of these models. I then discuss: the initial conditions of star cluster formation as traced by infrared dark clouds; the cluster formation timescale; and comparison of th...