Discovery of a tight brown dwarf companion to the low-mass star LHS 2397a

Melante Freed, Laird M Close, Nick Siegler

Research output: Contribution to journalArticle

46 Citations (Scopus)

Abstract

Using the adaptive optics system, Hokupa'a, at Gemini North, we have directly imaged a companion around the UKIRT faint standard M8 star LHS 2397a (FS 129) at a separation of 2.96 AU. Near-infrared photometry of the companion has shown it to be an L7.5 brown dwarf and confirmed the spectral type of the primary to be M8. We also derive a substellar mass of the companion of 0.068 M⊙, although masses in the range 0.061-0.069 M⊙ are possible, and the primary mass is 0.090 M⊙ (0.089-0.094 M⊙). Reanalysis of archival imaging from the Hubble Space Telescope has confirmed the secondary as a common proper motion object. This binary represents the first clear example of a brown dwarf companion within 4 AU of a low-mass star and should be one of the first late-L dwarfs to have a dynamical mass. As part of a larger survey of M8-L0 stars, this object may indicate that there is no "brown dwarf desert" around low-mass primaries.

Original languageEnglish (US)
Pages (from-to)453-458
Number of pages6
JournalAstrophysical Journal
Volume584
Issue number1 I
DOIs
StatePublished - Feb 10 2003

Fingerprint

stars
infrared photometry
deserts
proper motion
adaptive optics
Hubble Space Telescope
near infrared
desert

Keywords

  • Binaries: general
  • Instrumentation: adaptive optics
  • Stars: evolution
  • Stars: formation
  • Stars: individual (LHS 2397a)
  • Stars: low-mass, brown dwarfs

ASJC Scopus subject areas

  • Space and Planetary Science

Cite this

Discovery of a tight brown dwarf companion to the low-mass star LHS 2397a. / Freed, Melante; Close, Laird M; Siegler, Nick.

In: Astrophysical Journal, Vol. 584, No. 1 I, 10.02.2003, p. 453-458.

Research output: Contribution to journalArticle

Freed, Melante ; Close, Laird M ; Siegler, Nick. / Discovery of a tight brown dwarf companion to the low-mass star LHS 2397a. In: Astrophysical Journal. 2003 ; Vol. 584, No. 1 I. pp. 453-458.
@article{89b1472ba0a748af8862e536c090b128,
title = "Discovery of a tight brown dwarf companion to the low-mass star LHS 2397a",
abstract = "Using the adaptive optics system, Hokupa'a, at Gemini North, we have directly imaged a companion around the UKIRT faint standard M8 star LHS 2397a (FS 129) at a separation of 2.96 AU. Near-infrared photometry of the companion has shown it to be an L7.5 brown dwarf and confirmed the spectral type of the primary to be M8. We also derive a substellar mass of the companion of 0.068 M⊙, although masses in the range 0.061-0.069 M⊙ are possible, and the primary mass is 0.090 M⊙ (0.089-0.094 M⊙). Reanalysis of archival imaging from the Hubble Space Telescope has confirmed the secondary as a common proper motion object. This binary represents the first clear example of a brown dwarf companion within 4 AU of a low-mass star and should be one of the first late-L dwarfs to have a dynamical mass. As part of a larger survey of M8-L0 stars, this object may indicate that there is no {"}brown dwarf desert{"} around low-mass primaries.",
keywords = "Binaries: general, Instrumentation: adaptive optics, Stars: evolution, Stars: formation, Stars: individual (LHS 2397a), Stars: low-mass, brown dwarfs",
author = "Melante Freed and Close, {Laird M} and Nick Siegler",
year = "2003",
month = "2",
day = "10",
doi = "10.1086/345533",
language = "English (US)",
volume = "584",
pages = "453--458",
journal = "Astrophysical Journal",
issn = "0004-637X",
publisher = "IOP Publishing Ltd.",
number = "1 I",

}

TY - JOUR

T1 - Discovery of a tight brown dwarf companion to the low-mass star LHS 2397a

AU - Freed, Melante

AU - Close, Laird M

AU - Siegler, Nick

PY - 2003/2/10

Y1 - 2003/2/10

N2 - Using the adaptive optics system, Hokupa'a, at Gemini North, we have directly imaged a companion around the UKIRT faint standard M8 star LHS 2397a (FS 129) at a separation of 2.96 AU. Near-infrared photometry of the companion has shown it to be an L7.5 brown dwarf and confirmed the spectral type of the primary to be M8. We also derive a substellar mass of the companion of 0.068 M⊙, although masses in the range 0.061-0.069 M⊙ are possible, and the primary mass is 0.090 M⊙ (0.089-0.094 M⊙). Reanalysis of archival imaging from the Hubble Space Telescope has confirmed the secondary as a common proper motion object. This binary represents the first clear example of a brown dwarf companion within 4 AU of a low-mass star and should be one of the first late-L dwarfs to have a dynamical mass. As part of a larger survey of M8-L0 stars, this object may indicate that there is no "brown dwarf desert" around low-mass primaries.

AB - Using the adaptive optics system, Hokupa'a, at Gemini North, we have directly imaged a companion around the UKIRT faint standard M8 star LHS 2397a (FS 129) at a separation of 2.96 AU. Near-infrared photometry of the companion has shown it to be an L7.5 brown dwarf and confirmed the spectral type of the primary to be M8. We also derive a substellar mass of the companion of 0.068 M⊙, although masses in the range 0.061-0.069 M⊙ are possible, and the primary mass is 0.090 M⊙ (0.089-0.094 M⊙). Reanalysis of archival imaging from the Hubble Space Telescope has confirmed the secondary as a common proper motion object. This binary represents the first clear example of a brown dwarf companion within 4 AU of a low-mass star and should be one of the first late-L dwarfs to have a dynamical mass. As part of a larger survey of M8-L0 stars, this object may indicate that there is no "brown dwarf desert" around low-mass primaries.

KW - Binaries: general

KW - Instrumentation: adaptive optics

KW - Stars: evolution

KW - Stars: formation

KW - Stars: individual (LHS 2397a)

KW - Stars: low-mass, brown dwarfs

UR - http://www.scopus.com/inward/record.url?scp=0041527370&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0041527370&partnerID=8YFLogxK

U2 - 10.1086/345533

DO - 10.1086/345533

M3 - Article

VL - 584

SP - 453

EP - 458

JO - Astrophysical Journal

JF - Astrophysical Journal

SN - 0004-637X

IS - 1 I

ER -