Roger Julian

CanariCam: a multimode mid-infrared camera for the Gran Telescopio CANARIAS

The University of Florida is developing a mid-infrared camera for the 10.4-meter Gran Telescopio CANARIAS. CanariCam has four science modes and two engineering modes, which use the same 320 x 240-pixel, arsenic-doped silicon, blocked-impurity-band detector from Raytheon. Each mode can be remotely selected quickly during an observing sequence. The pixel scale is 0.08 arcsec, resulting in Nyquist sampling of the diffraction-limited point-spread-function at 8 μm, the shortest wavelength for which CanariCam is optimized. The total available field of view for imaging is 26 arcsec x 19 arcsec. The primary science mode will be diffraction-limited imaging using one of several available spectral filters in the 10 μm (8-14 μm) and 20 μm (16-25 μm) atmospheric windows. Any one of four plane gratings can be inserted for low and moderate-resolution (R = 100 - 1300) slit spectroscopy in the 10 and 20-μm regions. Insertion of appropriate field and pupil stops converts the camera into a coronagraph, while insertion of an internal rotating half-wave plate, a field mask, and a Wollaston prism converts the camera into a dual-beam polarimeter.

FLAMINGOS-2: the facility near-infrared wide-field imager and multi-object spectrograph for Gemini

Stephen Eikenberry, Reba Bandyopadhyay, J. Greg Bennett, Aaron Bessoff, Matt Branch, Miguel Charcos, Richard Corley, Curtis Dewitt, John-David Eriksen, Richard Elston, Skip Frommeyer, Anthony Gonzalez, Kevin Hanna, Michael Herlevich, David Hon, Jeff Julian, Roger Julian, Nestor Lasso, Antonio Marin-Franch, Jose Marti, Charlie Murphey, S. Nicholas Raines, William Rambold, David Rashkin, Craig Warner Department of Astronomy, University of Florida, Gainesville, FL 32611

The MOAO System of the IRMOS Near-Infrared Multi-Object Spectrograph for TMT

The near-Infrared Multi-Object Spectrograph (IRMOS) for TMT is one of the most powerful astronomical instruments ever envisioned. The combination of the collecting area of TMT, the unique image-sharpening capabilities of the Multi-Object Adaptive Optics (MOAO) system, and the multiplexing advantage of the multi-object integral-field spectra provided by the IRMOS back-end make it capable of addressing some of the leading scientific challenges of the coming decades. Here we present an overview of one potential IRMOS concept and then focus on the MOAO system. In particular we will describe our concept for the laser and natural guide star wavefront sensors, deformable mirrors and the calibration system of MOAO. For each of these design elements, we describe the key trade studies which help define each subsystem. From results of our studies, we assemble a MOAO ensquared energy budget. We find that 50% of the energy is ensquared within the 50 milli-arcsecond spatial pixel of the IRMOS integral field units for a wavelength of 1.65μm. Given the requirements placed on the MOAO system to achieve this performance, large ensquared energies can be achieved with even finer plate scales for wavelengths longer than 1.5μm.

IRMOS: The near-infrared multi-object spectrograph for the TMT

We present an overview of the near-InfraRed Multi-Object Spectrograph (IRMOS) for the Thirty Meter Telescope, as developed under a Feasibility Study at the University of Florida and Herzberg Institute of Astrophysics. IRMOS incorporates a multi-object adaptive optics correction capability over a 5-arcminute field of regard on TMT. Up to 20 independently-selectable target fields-of-view with ~2-arcsec diameter can be accessed within this field simultaneously. IRMOS provides near-diffraction-limited integral field spectroscopy over the 0.8-2.5 μm bandpass at R~1,000-20,000 for each target field. We give a brief summary of the Design Reference science cases for IRMOS. We then present an overview of the IRMOS baseline instrument design.

Optical-mechanical operation of the F2T2 filter: a tunable filter designed to search for First Light

The Flamingos-2 Tandem Tunable filter is a tunable, narrow-band filter, consisting of two Fabry-Perot etalons in series, capable of scanning to any wavelength from 0.95 to 1.35 microns with a spectral resolution of R~800. It is an accessory mode instrument for the near-IR Flamingos-2 imaging-spectrograph designed for the Gemini South 8m Observatory and will be fed through the upcoming Multi-Conjugate Adaptive Optics feed. The primary science goal of the F2T2 filter is to perform a ground-based search for the first star forming regions in the universe at redshifts of 7 < z < 11. The construction of the F2T2 filter is complete and it is currently in its calibration and commissioning phases. In this proceeding, we describe the calibration and performance of the instrument.

Systems engineering and performance modeling of the Gemini High-Resolution Near-Infrared Spectrograph (HRNIRS)

The High-resolution Near-infrared Spectrograph (HRNIRS) concept for the Gemini telescopes combines a seeing-limited R ~ 7000 cross-dispersed mode and an MCAO-fed near diffraction-limited R ~ 20000 multi-object mode into a single compact instrument operating over the 0.9 - 5.5 μm range. We describe the systems engineering and performance modeling aspects of this study, emphasizing simulations of high-precision radial verlocity measurements in the Gemini Cassegrain-focus instrument environment.

Day-one science with CanariCam, the Gran Telescopio Canarias multi-mode mid-infrared camera

CanariCam is the facility multi-mode mid-IR camera developed by the University of Florida for the 10-meter Gran Telescopio Canarias (GTC) on La Palma. CanariCam has four science modes that provide the GTC community with an especially powerful research tool for imaging, grating spectroscopy, coronagraphy, and dual-beam polarimetry. Instrument commissioning in the laboratory at the University of Florida indicates that all modes perform as required, and the next step is on-telescope commissioning. After commenting on the instrument status, we will review key features of each of these science modes, with emphasis on illustrating each mode with science examples that put the system performance, particularly the anticipated sensitivity, into perspective.

Conceptual design for a high-resolution infrared spectrograph for the 8-m Gemini telescopes

The High-Resolution Near-InfraRed Spectrograph (HRNIRS) concept for the Gemini telescopes combines a seeing limited R ~ 70000 cross-dispersed mode and an MCAO-fed near diffraction-limited R ~ 30000 multi-object mode into a single compact instrument operating over the 1 - 5 μm range. The HRNIRS concept was developed in response to proposals issued through the Aspen instrument process by Gemini. Here we review the science drivers and key functional requirements. We present a general overview of the instrument and estimate the limiting performance.

Characterization and testing of FLAMINGOS-2: the Gemini facility near-infrared multi-object spectrometer and wide-field imager

FLAMINGOS-2 is a near-infrared wide-field imager and fully cryogenic multi-object spectrometer for Gemini Observatory being built by the University of Florida. FLAMINGOS-2 can simultaneously carry 9 custom cryogenic multi-object slit masks exchangeable without thermally cycling the entire instrument. Three selectable grisms provide resolving powers which are ~1300 to ~3000 over the entire spectrograph bandpass of 0.9-2.5 microns. We present and discuss characterization data for FLAMINGOS-2 including imaging throughput, image quality, spectral performance, and noise performance. After a lengthy integration process, we expect that FLAMINGOS-2 will be in the midst of commissioning at Gemini South by the fall of 2008.