The ages and dimensions of Trapezium systems

Abstract

view Abstract Citations (61) References (31) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS The Ages and Dimensions of Trapezium Systems Abt, H. A. Abstract MK spectral types and memberships were obtained for 120 stars in 31 systems thought to be Trapezium systems. Twenty-eight optical components were found, after the removal of which, 17 systems are hierarchical and three have no companions. Practically all of the remaining Trapezium systems are either the same age or younger than the Hyades, i.e., less than 10 to the 8.9th years old. The maximum radii of Trapezium combined with hierarchical systems exhibit a dramatic decrease with primary spectral type or age T, ranging from about 50,000 AU for OB primaries to 1000 AU for G dwarfs. If stars have an observed binary separation of about 5000 AU, it is unlikely that the sun would have a stellar companion at 92,000 AU. A Ba II star with a physical companion, a star with strong double Ca II emission lines, and a chance projection of a nearby quadruple hierarchical system on a distant triple hierarchical system is discussed. Publication: The Astrophysical Journal Pub Date: May 1986 DOI: 10.1086/164207 Bibcode: 1986ApJ...304..688A Keywords: Orion Nebula; Spectrum Analysis; Star Distribution; Stellar Evolution; Stellar Magnitude; B Stars; Binary Stars; Emission Spectra; G Stars; Line Spectra; Stellar Motions; Tables (Data); Astrophysics; STARS: EVOLUTION; STARS: SPECTRAL CLASSIFICATION; STARS: STELLAR DYNAMICS; STARS: VISUAL MULTIPLES full text sources ADS | data products SIMBAD (46)