MLLA 468 , the SIMBAD biblio

2002ApJ...573..366M - Astrophys. J., 573, 366-393 (2002/July-1)

The luminosity and mass function of the Trapezium cluster: from B stars to the deuterium-burning limit.

MUENCH A.A., LADA E.A., LADA C.J. and ALVES J.

Abstract (from CDS):

We use the results of a new multiepoch, multiwavelength, near-infrared census of the Trapezium cluster in Orion to construct and analyze the structure of its infrared (K-band) luminosity function. Specifically, we employ an improved set of model luminosity functions to derive this cluster's underlying initial mass function (IMF) across the entire range of mass from OB stars to substellar objects down to near the deuterium-burning limit. We derive an IMF for the Trapezium cluster that rises with decreasing mass, having a Salpeter-like IMF slope until near ∼0.6 M where the IMF flattens and forms a broad peak extending to the hydrogen-burning limit, below which the IMF declines into the substellar regime. Independent of the details, we find that substellar objects account for no more than ∼22% of the total number of likely cluster members. Further, the substellar Trapezium IMF breaks from a steady power-law decline and forms a significant secondary peak at the lowest masses (10-20 times the mass of Jupiter). This secondary peak may contain as many as ∼30% of the substellar objects in the cluster. Below this substellar IMF peak, our K-band luminosity function (KLF) modeling requires a subsequent sharp decline toward the planetary mass regime. Lastly, we investigate the robustness of pre-main-sequence luminosity evolution as predicted by current evolutionary models, and we discuss possible origins for the IMF of brown dwarfs.

Abstract Copyright:

Journal keyword(s): Infrared: Stars - Galaxy: Open Clusters and Associations: Individual: Name: Trapezium - Stars: Low-Mass, Brown Dwarfs - Stars: Luminosity Function, Mass Function - Stars: Pre-Main-Sequence

VizieR on-line data: <Available at CDS (J/ApJ/573/366): table6.dat>

Nomenclature: Table 6: MLLA NNNNA (Nos 1-1010), N=1059.

CDS comments: Table 6: The 27 sources which were undetected and which have no cross-id in SIMBAD are not in SIMBAD.

Simbad objects: 1061

goto View the reference in ADS


2020.02.20-11:41:11

© Université de Strasbourg/CNRS

    • Contact