  The Space Coronagraph Optical Bench (SCoOB) is a high-contrast imaging
testbed built to demonstrate starlight suppression techniques at visible
wavelengths in a space-like vacuum environment. The testbed is designed to
achieve ${<}10^{-8}$ contrast from $3-10\lambda/D$ in a one-sided dark hole
using a liquid crystal vector vortex waveplate and a 952-actuator Kilo-C
deformable mirror (DM) from Boston Micromachines (BMC). We have recently
expanded the testbed to include a field stop for mitigation of stray/scattered
light, a precision-fabricated pinhole in the source simulator, a Minus K
passive vibration isolation table for jitter reduction, and a low-noise
vacuum-compatible CMOS sensor. We report the latest contrast performance
achieved using implicit electric field conjugation (iEFC) at a vacuum of
${\sim}10^{-6}$ Torr and over a range of bandpasses with central wavelengths
from 500 to 650nm and bandwidths (BW) from $\ll 1\%$ to 15\%. Our jitter in
vacuum is $<3\times10^{-3} \lambda/D$, and the best contrast performance
to-date in a half-sided D-shaped dark hole is $2.2\times10^{-9}$ in a $\ll 1
\%$ BW, $4\times10^{-9}$ in a 2\% BW, and $2.5\times10^{-8}$ in a 15\% BW.
