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Very Low Mass Stellar Populations in Star-Forming Regions: Near-Infrared Luminosity Functions and Mass Functions

Published online by Cambridge University Press:  26 May 2016

Yumiko Oasa*
Affiliation:
National Space Development Agency of Japan / Earth Observation Research Center, Harumi Island Triton Square Office Tower X 23F, 1-8-10, Harumi, Chuo-ku, Tokyo 104-6023, Japan

Abstract

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We briefly describe recent studies of the low-mass young stellar populations including substellar objects and of their luminosity functions and mass functions, especially at lower-ends, in different star-forming regions. The mass function is determined by the technique based on the near-infrared photometry for estimating stellar luminosities and then translating them into stellar masses. We compare the local environmental characteristics of regions in which high-mass stars form with those of regions producing only low-mass stars and intermediate stars. We find that there exist numerous very low-mass YSO candidates including young brown dwarfs and young isolated objects with planetary masses in common. Further, the luminosity functions and mass functions in the star-forming regions might not have a uniform shape below the hydrogen-burning limit.

Type
Part 2. Observations of Recently Born Substellar Objects
Copyright
Copyright © Astronomical Society of the Pacific 2001 

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