A New Look at the Binary Characteristics of Massive Stars
| dc.creator | Kobulnicky, Henry A. | |
| dc.creator | Fryer, Chris L. | |
| dc.date | 2006-05-02 | |
| dc.date | 2007-07-31 | |
| dc.date.accessioned | 2026-07-07T08:21:07Z | |
| dc.date.available | 2026-07-07T08:21:07Z | |
| dc.description | We constrain the properties of massive binaries by comparing radial velocity data of Cygnus OB2 with Monte Carlo models. Our comparisons test several popular prescriptions for massive binary parameters. We explore a range of true binary fraction, F, a range of power-law slopes, α, describing the distribution of companion masses, and a range of power-law slopes, β, describing the distribution of orbital separations. We also consider distributions of secondary masses described by a Miller-Scalo type initial mass function and by a two-component IMF that includes a substantial ``twin'' population with M_2 ~ M_1. We show that binary fractions F<0.7 are considerably less probable than F>0.8. Thus, the true binary fraction is high. For F=1.0 and a distribution of orbital separations near the canonical Opik's Law distribution (i.e., flat; β=0), the power law slope of the mass ratio distribution is α= -0.6 - 0.0. For F~0.8, αis somewhat larger, in the range -0.4 - 1.0. In any case, the secondary star mass function is inconsistent with a Miller-Scalo -like IMF unless the lower end is truncated below ~ 2--4 solar masses. In other words, massive stars preferentially have massive companions. The best fitting models are described by a Salpeter or Miller-Scalo IMF for 60% of secondary star masses with the other 40% of secondaries having M_2 ~ M_1, i.e., ``twins''. These best-fitting model parameters simultaneously predict the fraction of type Ib/c supernovae to be 30-40% of all core-collapse supernovae, in agreement with recent observational estimates. | |
| dc.description | Replacement for astro-ph/0605069; Substantial changes from original version; 47 pages, 16 figures; Accepted for publication in the Astrophysical Journal | |
| dc.identifier | https://arxiv.org/abs/astro-ph/0605069 | |
| dc.identifier | http://arxiv.org/abs/astro-ph/0605069 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/135261 | |
| dc.subject | Astrophysics | |
| dc.title | A New Look at the Binary Characteristics of Massive Stars | |
| dc.type | text |