Low-Mass Runaway Stars from the Orion Trapezium Cluster

Abstract

In the course of a search for common proper motion binaries, in the Jones & Walker (JW) catalogue of proper motions in the Orion Nebula Cluster, we came across several faint stars with proper motions larger than one arcsecond per century and probabilities of membership P larger than 0.90. Such stars are interesting because they could be low-mass runaway stars recently accelerated by n-body interactions in compact multiple systems. Of particular interest among these stars is JW 451, which has a P = 0.98, the largest transverse velocity among all the stars with P larger or equal than 0.5 (69 km/s), and a proper motion vector which suggests that it was accelerated by the component C of the Trapezium some 1000 years ago. A closer examination of those JW stars with proper motion larger than one arcsec per century revealed that two other stars, JW 349 and JW 355 (with transverse velocities of 38 and 90 km/s respectively), in spite of being listed with P = 0 by JW, should also be considered part of the cluster, because these objects are also externally ionized proplyds. In fact, Hillenbrand (1997) assigns to them probabilities of membership of 0.99. Moreover, the proper motion errors of these two stars are relatively small, and so they are good candidates to be runaway stars recently accelerated in the Orion Nebula Cluster.

References in corpus (4)

• Proper Motions of the BN Object and the I Radio Source in Orion: Where and When Did BN Become a Runaway Star?
• The Becklin-Neugebauer Object as a Runaway B Star, Ejected 4000 years ago from the theta^1C system
• Ejection of a Low Mass Star in a Young Stellar System in Taurus
• High Resolution Images of Orbital Motion in the Trapezium Cluster: First Scientific Results from the MMT Deformable Secondary Mirror Adaptive Optics System

Cited by in corpus (16)

• The Gould's Belt Distances Survey (GOBELINS) II. Distances and structure towards the Orion Molecular Clouds
• Kinematic Structure of the Orion Nebula Cluster and its Surroundings
• Proper Motions of the BN Object and the I Radio Source in Orion: Where and When Did BN Become a Runaway Star?
• Runaway and walkaway stars from the ONC with Gaia DR2
• Evidence for feedback and stellar-dynamically regulated bursty star cluster formation: the case of the Orion Nebula Cluster
• The IMF of stellar clusters: effects of accretion and feedback
• A solution to the proplyd lifetime problem
• Characterizing the High-Velocity Stars of RAVE: The Discovery of a Metal-Rich Halo Star Born in the Galactic Disk
• On the formation of trapezium-like systems
• Radio Measurements of the stellar proper motions in the core of the Orion Nebula Cluster
• Dynamical evolution of star-forming regions: III. Unbound stars and predictions for Gaia
• Runaways and shells around the CMa OB1 association
• HST astrometry in the Orion Nebula Cluster: census of low-mass runaways
• HST Images Do Not Support the Presence of Three High Velocity, Low-Mass Stars in the Core of the Orion Nebula Cluster
• Bayesian ages of local young stellar associations I. Through the expansion rate method
• LP 543-25: a rare low-mass runaway disk star