A new brown dwarf desert? A scarcity of wide ultracool binaries

被引：37
作者：
Allen, Peter R.
Koerner, David W.
McElwain, Michael W.
Cruz, Kelle L.
Reid, I. Neill
机构：
[1] Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA
[2] No Arizona Univ, Dept Phys & Astron, Flagstaff, AZ 86011 USA
[3] Univ Calif Los Angeles, Dept Phys & Astron, Los Angeles, CA 90024 USA
[4] Amer Museum Nat Hist, Dept Astrophys, New York, NY 10024 USA
[5] Space Telescope Sci Inst, Baltimore, MD 21218 USA
来源：
ASTRONOMICAL JOURNAL | 2007年 / 133卷 / 03期
关键词：
binaries : general; stars; low-mass; brown dwarfs;
D O I：
10.1086/510346
中图分类号：
P1 [天文学];
学科分类号：
0704 ;
摘要：
We present the results of a deep-imaging search for wide companions to low-mass stars and brown dwarfs using NSFCam on the Infrared Telescope Facility. We searched a sample of 132 M7-L8 dwarfs to magnitude limits of J similar to 20.5 and K similar to 18.5, corresponding to secondary-to-primary mass ratios of similar to 0.5. No companions were found with separations between 2" and 31" (similar to 40 to similar to 1000 AU). This null result implies a wide companion frequency below 2.3% at the 95% confidence level within the sensitivity limits of the survey. Preliminary modeling efforts indicate that we could have detected 85% of companions more massive than 0.05 M-circle dot and 50% above 0.03 M-circle dot.
引用
收藏
页码：971 / 978
页数：8
相关论文
共 40 条
[1]   The substellar mass function: A Bayesian approach [J].
Allen, PR ;
Koerner, DW ;
Reid, IN ;
Trilling, DE .
ASTROPHYSICAL JOURNAL, 2005, 625 (01) :385-397
[2]  
ALLEN PR, 2006, UNPUB APJ
[3]  
[Anonymous], B ASTRON SOC BRAZIL
[4]   The first wide ultracool binary dwarf in the field:: DENIS-J055146.0-443412.2 (M8.5+L0) [J].
Billères, M ;
Delfosse, X ;
Beuzit, JL ;
Forveille, T ;
Marchal, L ;
Martín, EL .
ASTRONOMY & ASTROPHYSICS, 2005, 440 (02) :L55-L58
[5]   Multiplicity of nearby free-floating ultracool dwarfs:: A Hubble Space Telescope WFPC2 search for companions [J].
Bouy, H ;
Brandner, W ;
Martín, EL ;
Delfosse, X ;
Allard, F ;
Basri, G .
ASTRONOMICAL JOURNAL, 2003, 126 (03) :1526-1554
[6]   T dwarfs and the substellar mass function. I. Monte Carlo simulations [J].
Burgasser, AJ .
ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES, 2004, 155 (01) :191-207
[7]   Binarity in brown dwarfs:: T dwarf binaries discovered with the Hubble Space Telescope Wide Field Planetary Camera 2 [J].
Burgasser, AJ ;
Kirkpatrick, JD ;
Reid, IN ;
Brown, ME ;
Miskey, CL ;
Gizis, JE .
ASTROPHYSICAL JOURNAL, 2003, 586 (01) :512-526
[8]   The spectra of T dwarfs. I. Near-infrared data and spectral classification [J].
Burgasser, AJ ;
Kirkpatrick, JD ;
Brown, ME ;
Reid, IN ;
Burrows, A ;
Liebert, J ;
Matthews, K ;
Gizis, JE ;
Dahn, CC ;
Monet, DG ;
Cutri, RM ;
Skrutskie, MF .
ASTROPHYSICAL JOURNAL, 2002, 564 (01) :421-451
[9]   The theory of brown dwarfs and extrasolar giant planets [J].
Burrows, A ;
Hubbard, WB ;
Lunine, JI ;
Liebert, J .
REVIEWS OF MODERN PHYSICS, 2001, 73 (03) :719-765
[10]   A giant planet candidate near a young brown dwarf - Direct VLT/NACO observations using IR wavefront sensing [J].
Chauvin, G ;
Lagrange, AM ;
Dumas, C ;
Zuckerman, B ;
Mouillet, D ;
Song, I ;
Beuzit, JL ;
Lowrance, P .
ASTRONOMY & ASTROPHYSICS, 2004, 425 (02) :L29-L32
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