TY - JOUR
T1 - High-contrast 3.8μm imaging of the brown dwarf/planet-mass companion to GJ 758
AU - Currie, Thayne
AU - Bailey, Vanessa
AU - Fabrycky, Daniel
AU - Murray-Clay, Ruth
AU - Rodigas, Timothy
AU - Hinz, Phil
N1 - Copyright:
Copyright 2015 Elsevier B.V., All rights reserved.
PY - 2010/10/1
Y1 - 2010/10/1
N2 - We present L ′-band (3.8μm) MMT/Clio high-contrast imaging data for the nearby star GJ 758, which was recently reported by Thalmann et al. to have one-possibly two-faint comoving companions (GJ 758B and "C," respectively). GJ 758B is detected in two distinct data sets. Additionally, we report a possible detection of the object identified by Thalmann et al. as "GJ 758C" in our more sensitive data set, though it is likely a residual speckle. However, if it is the same object as that reported byThalmann et al. it cannot be a companion in a bound orbit. GJ 758B has an H -L ′ color redder than nearly all known L-T8 dwarfs. Based on comparisons with the COND evolutionary models, GJ 758B has Te ∼ 560 K -90K+150K and a mass ranging from ∼10-20 MJ if it is ∼1 Gyr old to ∼ 25-40 MJ if it is 8.7Gyr old. GJ 758B is likely in a highly eccentric orbit, e∼0.73 -0.21+ 0.12 ,with a semimajor axis of∼44AU-14AU +32AU. Though GJ 758B is sometimes discussed within the context of exoplanet direct imaging, its mass is likely greater than the deuterium-burning limit and its formation may resemble that of binary stars rather than that of Jovian-mass planets.
AB - We present L ′-band (3.8μm) MMT/Clio high-contrast imaging data for the nearby star GJ 758, which was recently reported by Thalmann et al. to have one-possibly two-faint comoving companions (GJ 758B and "C," respectively). GJ 758B is detected in two distinct data sets. Additionally, we report a possible detection of the object identified by Thalmann et al. as "GJ 758C" in our more sensitive data set, though it is likely a residual speckle. However, if it is the same object as that reported byThalmann et al. it cannot be a companion in a bound orbit. GJ 758B has an H -L ′ color redder than nearly all known L-T8 dwarfs. Based on comparisons with the COND evolutionary models, GJ 758B has Te ∼ 560 K -90K+150K and a mass ranging from ∼10-20 MJ if it is ∼1 Gyr old to ∼ 25-40 MJ if it is 8.7Gyr old. GJ 758B is likely in a highly eccentric orbit, e∼0.73 -0.21+ 0.12 ,with a semimajor axis of∼44AU-14AU +32AU. Though GJ 758B is sometimes discussed within the context of exoplanet direct imaging, its mass is likely greater than the deuterium-burning limit and its formation may resemble that of binary stars rather than that of Jovian-mass planets.
KW - Brown dwarfs
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U2 - 10.1088/2041-8205/721/2/L177
DO - 10.1088/2041-8205/721/2/L177
M3 - Article
AN - SCOPUS:78649295689
VL - 721
SP - L177-L181
JO - Astrophysical Journal Letters
JF - Astrophysical Journal Letters
SN - 2041-8205
IS - 2 PART 2
ER -