▪ Abstract The establishment of new spectral classes cooler than type M has had a brief, yet
already rich, history. Prototypes of the new “L dwarf” and “T dwarf” classes were first found in …

We present final Spitzer trigonometric parallaxes for 361 L, T, and Y dwarfs. We combine
these with prior studies to build a list of 525 known L, T, and Y dwarfs within 20 pc of the …

We present the results of a comprehensive assessment of companions to solar-type stars. A
sample of 454 stars, including the Sun, was selected from the Hipparcos catalog with π> 40 …

We present the first results from our high-precision infrared (IR) astrometry program at the
Canada–France–Hawaii Telescope. We measure parallaxes for 83 ultracool dwarfs …

The last decade of direct imaging (DI) searches for sub-stellar companions has uncovered a
widely diverse sample that challenges the current formation models, while highlighting the …

We present the full results of our decade-long astrometric monitoring programs targeting 31
ultracool binaries with component spectral types M7–T5. Joint analysis of resolved imaging …

Trigonometric parallax determinations are presented for 28 late-type dwarfs and brown
dwarfs, including eight M dwarfs with spectral types between M7 and M9. 5, 17 L dwarfs with …

We report parallax measurements for 70 ultracool dwarfs (UCDs) including 11 late-M, 32 L,
and 27 T dwarfs. In this sample, 14 M and L dwarfs exhibit low surface gravity features, 6 are …

We present a new volume-limited sample of L0–T8 dwarfs out to 25 pc defined entirely by
parallaxes, using our recent measurements from UKIRT/WFCAM along with Gaia DR2 and …

We present the discovery of two T dwarf binaries, 2MASS 1225-2739AB and 2MASS 1534-
2952AB, identified in a sample of 10 T dwarfs imaged with the Hubble Space Telescope …