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تسجيل مستخدم جديدA New Brown Dwarf Desert? A Scarcity of Wide Ultracool Binaries
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We present the results of a deep-imaging search for wide companions to low-mass stars and brown dwarfs using NSFCam on IRTF. We searched a sample of 132 M7-L8 dwarfs to magnitude limits of $J sim 20.5$ and $K sim 18.5$, corresponding to secondary-primary mass ratios of $sim 0.5$. No companions were found with separations between $2{arcsec}$ to $31{arcsec}$ ($sim$40 AU to $sim$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 $0.05 M_{odot}$ and 50% above $0.03 M_{odot}$.
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