The Multi-spectral Visible Imaging Camera (MVIC) detector is a time-delay and integration (TDI) CCD with 4, 8, 16, 32, and 64 TDI modes. MVIC is scheduled to fly as part of the instrument suite on the Lucy mission to the Trojans launching in 2021. We present here the pre-delivery SwRI Detector Characterization Lab (SDCL) data of the Flight (FM) and Flight Spare (FS) from 370 to 925nm. The MVIC sensor consists of six broad-band top-hat filters on a single sapphire substrate developed by VIAVI Solutions and six CCDs on a single wafer developed by Semiconductor Technology Associates (STA). We have calibrated both the FS and FM for read noise, dark current, linearity, quantum efficiency, and total system throughput. The data were collected using standard Photon Transfer Curve techniques at strategically chosen wavelengths corresponding to center and edge of the bandpass filters. Each system was also calibrated for spuriously operational pixels and cosmetic defects. The pixel response function is mapped on a pixel-by-pixel basis for the 64 TDI mode.
SCORPIO is the next facility instrument for the Gemini South telescope at Cerro Pachon, Chile. SCORPIO’s main science driver is the detection and monitoring of faint time-domain events, in particular the follow-up of discoveries by the Vera C. Rubin Observatory, but it can also carry out with unique efficiency a large variety of astrophysical programs. The instrument has recently passed Critical Design Review and is now in its Assembly, Integration and Verification phase. In this paper we provide an updated overview of the final instrument design and the main performance parameters in light of the science drivers.
The SwRI Detector Characterization Lab (SDCL) was established in order to facilitate the rapid calibration of large numbers of detector arrays for upcoming ground and space missions. The SDCL is equipped with a McPherson monochromator with exchangeable gratings and light sources enabling wavelength coverage from 0.3 to 5.0 micron at sub nanometer resolution. The SDCL also has cryostats capable of maintaining thermal control of detector subassemblies and transfer optics to a precision of 0.1K at 77K and 0.01K at 4K. Using this calibration system, we have calibrated the EEM and ETU detector for read noise, dark current, modulation transfer function, quantum efficiency, cross talk, and total system throughput. The data were collected using standard Photon Transfer Curve techniques at the various wavelengths corresponding to the MVIC filter bandpasses. Here, we will present the data for the engineering unit, the methodology used to perform the calibration, and the steps forward for calibration of the flight unit.
SCORPIO (Spectrograph and Camera for Observation of Rapid Phenomena in the Infrared and Optical) is the new workhorse instrument for the Gemini South Telescope in Chile. Originally proposed in response to the Gen4#3 solicitation, SCORPIO is a unique fast-multicolor imager and ultra-wide band spectrograph capable of rapid exposures for high time-resolution images and spectra. SCORPIO consists of 8 separate channels (corresponding to the standard wavebands g, r, i, z, Y, H, J, K) that can operate with different exposure times. Each channel can be used in imaging or long-slit mode, with independent readout timing. In this report we illustrate the detectors, the control systems, and the observing modes that will be available with SCORPIO.
We present the current status of the SCORPIO project, the facility instrument for Gemini South designed to perform follow up studies of transients in the LSST era while carrying out with unique efficiency a great variety of astrophysical programs. SCORPIO operates in the wavelength range 385-2350 nanometers, observing simultaneously in the grizYJHK bands. It can be used both in imaging (seeing limited) and spectroscopic (long-slit) mode, and thanks to the use of frame-transfer CCDs it can monitor variable sources with milli-second time-resolution. The project has recently passed PDR and is on schedule to be commissioned at the time of the LSST first light.
As the costs of space missions continue to rise, the demand for compact, low mass, low-cost technologies that maintain
high reliability and facilitate high performance is increasing. One such technology is the stabilized dispersive focal plane
system (SDFPS). This technology provides image stabilization while simultaneously delivering spectroscopic or direct
imaging functionality using only a single optical path and detector. Typical systems require multiple expensive optical
trains and/or detectors, sometimes at the expense of photon throughput. The SDFPS is ideal for performing wide-field
low-resolution space-based spectroscopic and direct-imaging surveys. In preparation for a suborbital flight, we have
built and ground tested a prototype SDFPS that will concurrently eliminate unwanted image blurring due to the lack of
adequate platform stability, while producing images in both spectroscopic and direct-imaging modes. We present the
overall design, testing results, and potential scientific applications.
The Hobby-Eberly Telescope Dark Energy eXperiment [HETDEX] will employ over 43,000 optical fibers to feed light
to 192 Visible Integral-Field Replicable Unit Spectrographs [VIRUS]. Each VIRUS instrument is fed by 224 fibers. To
reduce cost, the spectrographs are combined into pairs; thus, two bundles of 224 fibers are combined into a single
Integral Field Unit [IFU] of 448 fibers. On the input end the fibers are arranged in a square 'dense-pack' array at the
HET focal surface. At the output end the IFU terminates in two separate linear arrays which provide entry slits for each
spectrometer unit. The IFU lengths must be kept to an absolute minimum to mitigate losses; however, consideration of
overall project cost and duration of the science mission have resulted in the generation of two competing concepts.
Multiple axes of motion are imposed on the IFUs as they span the shortest distance from the focal surface to each
VIRUS unit. Arranging and supporting 96 IFUs, that have a total mass over 450 kg, in a manner that is compatible with
these complex translations, together with the management of accompanying forces on the tracking mechanism of the
HET, presents a significant technical challenge, which is further compounded by wind buffeting. The longer IFU
concept is favored due to overall project cost, but requires tests to assure that the fibers can withstand forces associated
with a height differential of 16.25 meters without FRD losses or breakage.