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The Goodman Spectrograph is an imaging, multi-object spectrograph for the SOuthern Astrophysical Research telescope (SOAR). It is one of the first designed to take advantage of Volume Phase Holographic (VPH) gratings by employing an articulated camera. This aspect of the mechanical design has had complicating effects on a number of usually simple systems, and has led to some unorthodox solutions. The spectrograph is also highly optimized for efficiency from 320 to 850 nm, and designed for rapid configuration changes, so that its throughput makes it competitive with instruments on larger telescopes. We present the high level requirements that have driven the mechanical and electronic systems, and show their implementation in the completed instrument. It is too early to assess the overall system performance, but tests of the modular subsystems show promising results. We discuss the expected overall performance and discuss mitigation strategies should that performance fall short of our goals.

We demonstrate the advantages of a ferroelectric liquid crystal spatial light modulator for optical tweezer array applications. The fast switching speeds of the ferroelectric device (compared to conventional nematic systems) is shown to enable very rapid reconfiguration of trap geometries, controlled, high speed particle movement, and tweezer array multiplexing.

PROMPT (Panchromatic Robotic Optical Monitoring and PolarimetryTelescopes) observed the early-time optical afterglow of GRB 060607A and obtained a densely sampled multiwavelength light curve that begins only tens of seconds after the GRB. Located at Cerro Tololo Inter-American Observatory in Chile, PROMPT is designed to observe the afterglows of γ-ray bursts using multiple automated 0.4-m telescopes that image simultaneously in many filters when the afterglow is bright and may be highly variable. The data span the interval from 44 seconds after the GRB trigger to 3.3 hours in the Bgri filters. We observe an initial peak in the light curve at approximately three minutes, followed by rebrightenings peaking around 40 minutes and again at 66 minutes. Although our data overlap with the early Swift γ-ray and x-ray light curves, we do not see a correlation between the optical and high-energy flares. We do not find evidence for spectral evolution throughout the observations. We model the variations in the light curves and find that the most likely cause of the rebrightening episodes is a refreshment of the forward shock preceded by a rapidly fading reverse shock component, although other explanations are plausible.