Mechanism for ejecting stars from the Galactic plane

Conference · Sat Aug 01 04:00:00 EDT 1992

OSTI ID:10167690

Leonard, P J.T.

The two most popular mechanisms for ejecting stars from the plane of the Galaxy are the supernova ejection and dynamical (or cluster) ejection scenarios. These two processes make definite predictions regarding the properties of the runaway stars (e.g., mass-velocity diagram and binary characteristics). The relations between mass and velocity predicted by the two theories are more similar to each other than had been previously believed. The binary properties of the runaways provide the best means of discriminating between the two scenarios. Supernova ejection predicts a high frequency of neutron star companions ({approx_gt} 50%) and a very low frequency of runaway binaries consisting of two normal stars ({approx_equal} 1%), while dynamical ejection predicts modest frequencies of both normal ({approx_equal} 10%) and neutron star companions ({approx_lt} 10%). The observed binary characteristics of runaway stars are more consistent with dynamical rather than supernova ejection. The normality of the runaways and the production rate per unit surface area of the Galactic disk may be two other areas where the predictions of the two theories differ.

• Research Organization: Los Alamos National Lab., NM (United States)
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: W-7405-ENG-36
• OSTI ID: 10167690
• Report Number(s): LA-UR--92-2219; CONF-9205226--1; ON: DE92018375
• Country of Publication: United States
• Language: English

Related Subjects

661300
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
GALACTIC EVOLUTION
GALAXIES
MOTION
OTHER ASPECTS OF PHYSICAL SCIENCE
STAR MODELS
STARS
SUPERNOVAE
VELOCITY