THE SOLAR NEIGHBORHOOD. XXVIII. THE MULTIPLICITY FRACTION OF NEARBY STARS FROM 5 TO 70 AU AND THE BROWN DWARF DESERT AROUND M DWARFS

• Published in: The Astronomical journal Vol. 144; no. 2; pp. 1 - 19
• Main Authors: Dieterich, Sergio B, Henry, Todd J, Golimowski, David A, Krist, John E, Tanner, Angelle M
• Format: Journal Article
• Language: English
• Published: United States 01.08.2012
• Subjects: ASTRONOMY; ASTROPHYSICS; ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; BINARY STARS; Brown dwarf stars; CAMERAS; COLOR; DATA ANALYSIS; Deserts; DIAGRAMS; DWARF STARS; Hubble Space Telescope; MASS; METHANE; MULTIPLICITY; OPTICAL FILTERS; PHOTOMETRY; RESOLUTION; SENSITIVITY; Separation; Solar neighborhood; Stars; STATISTICS; TELESCOPES
• ISSN: 0004-6256; 1538-3881; 1538-3881
• DOI: 10.1088/0004-6256/144/2/64

We report on our analysis of Hubble Space Telescope/NICMOS snapshot high-resolution images of 255 stars in 201 systems within ~10 pc of the Sun. Photometry was obtained through filters F110W, F180M, F207M, and F222M using NICMOS Camera 2. We establish magnitude and separation limits for which companions can be ruled out for each star in the sample, and then perform a comprehensive sensitivity and completeness analysis for the subsample of 138 M dwarfs in 126 systems. Considering these results and results from several other studies, we argue that the so-called brown dwarf desert extends to binary systems with low-mass primaries and is largely independent of primary mass, mass ratio, and separations. While focusing on companion properties, we discuss how the qualitative agreement between observed companion mass functions and initial mass functions suggests that the paucity of brown dwarfs in either population may be due to a common cause and not due to binary formation mechanisms.