http://arxiv.org/abs/1710.11127
I use the multi-epoch astrometry from the Wide-field Infrared Survey Explorer (WISE) to demonstrate a method to measure proper motions and trigonometric parallaxes with precisions of $\sim$3 mas yr$^{-1}$ and $\sim$7 mas, respectively, for low-mass stars and brown dwarfs. This method relies on WISE single exposures (Level 1b frames) and a Markov Chain Monte Carlo method. I discuss the limitations of Gaia in observing low-mass stars and brown dwarfs, and show that WISE will be able to measure astrometry past the limit of Gaia (sources fainter than $W2\approx11$). I apply this method to WISE data of 17 nearby ($\lesssim$ 17 pc) dwarfs with spectral types between M6.5-Y2 and previously measured trigonometric parallaxes, and show good agreement between this method and literature values. I provide new astrometric measurements for ten additional low-mass dwarfs with spectral types between M6-T5.5 and with estimated photometric distances $<$ 17 pc. Only three of these objects are contained within Gaia Data Release 1.
C. Theissen
Wed, 1 Nov 17
47/63
Comments: Submitted to ApJ