The space frequency and origin of the runaway O and B stars

Abstract

Determinations of space frequency for runaway O and B stars are in verypoor agreement, and many possible sources of systematic errors have beenput forward. This paper investigates these sources, as well as others,and presents means for determining unbiased (true) space frequencies.When corrected for major sources of systematic error, space frequencydeterminations for the runaway O stars are in very good agreement butless so for the B-type runaways. The true space frequencies of runaway Oand B stars are, respectively, 46 percent and 4 percent, as discussed inthis paper. The former value is very supportive, along with otherarguments presented in this paper, for runaway O stars being producedfrom supernova explosions in massive binaries. The origin of the B-typerunaways is less clear.