A New Brown Dwarf Desert? A Scarcity of Wide Ultracool Binaries

2006/10/25 by Peter R. Allen, David W. Koerner, Michael W. McElwain +2
Physics and Astronomy · Social Sciences · #Astronomy and Astrophysical Research #Brown dwarf #Circumbinary planet #Educational Leadership and Practices #Magnitude (astronomy) #Range (aeronautics) #Sample (material) #Sensitivity (control systems) #Stars #Stellar, planetary, and galactic studies #astro-ph

paper · pdf · doi:10.1086/510346

published as Astron.J.133:971-978,2007 · 27 pages, 8 figures, 3 tables: accepted to the Astronomical Journal

arxiv created 2006/10/25 · openalex publication_date 2007/01/31 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/08

Abstract

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 ∼ 20.5 and K ∼ 18.5, corresponding to secondary-to-primary mass ratios of ∼0.5. No companions were found with separations between 2'' and 31'' (∼40 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 ⊙ and 50% above 0.03 M ⊙ .

Citations

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