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We present a volume-limited, spectroscopically-verified sample of M7$-$L5 ultracool dwarfs within 25,pc. The sample contains 410 sources, of which $93%$ have trigonometric distance measurements ($80%$ from textit{Gaia} DR2), and $81%$ have low-resolution ($Rsim120$), near-infrared (NIR) spectroscopy. We also present an additional list of 60 sources which may be M7$-$L5 dwarfs within 25,pc when distance or spectral type uncertainties are taken into account. The spectra provide NIR spectral and gravity classifications, and we use these to identify young sources, red and blue $J-K_S$ color outliers, and spectral binaries. We measure very low gravity and intermediate gravity fractions of $2.1^{+0.9}_{-0.8}%$ and $7.8^{+1.7}_{-1.5}%$, respectively; fractions of red and blue color outliers of $1.4^{+0.6}_{-0.5}$% and $3.6^{+1.0}_{-0.9}$%, respectively; and a spectral binary fraction of $1.6^{+0.5}_{-0.5}%$. We present an updated luminosity function for M7$-$L5 dwarfs continuous across the hydrogen burning limit that agrees with previous studies. We estimate our completeness to range between $69-80%$ when compared to an isotropic model. However, we find that the literature late-M sample is severely incomplete compared to L dwarfs, with completeness of $62^{+8}_{-7}%$ and $83^{+10}_{-9}%$, respectively. This incompleteness can be addressed with astrometric-based searches of ultracool dwarfs with textit{Gaia} to identify objects previously missed by color- and magnitude-limited surveys.
We conducted a volume-limited survey at 4.9 GHz of 32 nearby ultracool dwarfs with spectral types covering the range M7 -- T8. A statistical analysis was performed on the combined data from the present survey and previous radio observations of ultrac
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 literature parallaxes. With 369 members, our sample is the largest parallax-def
Kepler K2 long cadence data are used to study white light flares in a sample of 45 L dwarfs. We identified 11 flares on 9 L dwarfs with equivalent durations of (1.3 - 198) hr and total (UV/optical/IR) energies of $geq$0.9 $times$ 10$^{32}$ erg. Two s
The Canada-France Brown Dwarf Survey is a wide eld survey for cool brown dwarfs conducted with the MegaCam camera on the CFHT telescope. Our objectives are to nd ultracool brown dwarfs and to constrain the eld brown dwarf mass function from a large a
We present a near-infrared (0.9-2.4 microns) spectroscopic study of 73 field ultracool dwarfs having spectroscopic and/or kinematic evidence of youth (~10-300 Myr). Our sample is composed of 48 low-resolution (R~100) spectra and 41 moderate-resolutio