The MAPS Adaptive Secondary Mirror: First Light, Laboratory Work, and Achievements

The MMT Adaptive Optics exoPlanet Characterization System (MAPS) is a comprehensive update to the first generation MMT adaptive optics system (MMTAO), designed to produce a facility class suite of instruments whose purpose is to image nearby exoplanets. The system's adaptive secondary mirror (ASM), although comprised in part of legacy components from the MMTAO ASM, represents a major leap forward in engineering, structure and function. The subject of this paper is the design, operation, achievements and technical issues of the MAPS adaptive secondary mirror. We discuss laboratory preparation for on-sky engineering runs, the results of those runs and the issues we discovered, what we learned about those issues in a follow-up period of laboratory work, and the steps we are taking to mitigate them.Comment: 22 pages, 22 images, 2 tables, submitted to SPIE Proceedings (Unconventional Imaging, Sensing and Adaptive Optics 2023 Conference

Final Design and On-Sky Testing of the iLocater SX Acquisition Camera: Broadband Single-Mode Fiber Coupling

Enabling efficient injection of light into single-mode fibers (SMFs) is a key requirement in realizing diffraction-limited astronomical spectroscopy on ground-based telescopes. SMF-fed spectrographs, facilitated by the use of adaptive optics (AO), offer distinct advantages over comparable seeing-limited designs, including higher spectral resolution within a compact and stable instrument volume, and a telescope independent spectrograph design. iLocater is an extremely precise radial velocity (EPRV) spectrograph being built for the Large Binocular Telescope (LBT). We have designed and built the front-end fiber injection system, or acquisition camera, for the SX (left) primary mirror of the LBT. The instrument was installed in 2019 and underwent on-sky commissioning and performance assessment. In this paper, we present the instrument requirements, acquisition camera design, as well as results from first-light measurements. Broadband single-mode fiber coupling in excess of 35% (absolute) in the near-infrared (0.97-1.31{\mu}m) was achieved across a range of target magnitudes, spectral types, and observing conditions. Successful demonstration of on-sky performance represents both a major milestone in the development of iLocater and in making efficient ground-based SMF-fed astronomical instruments a reality.Comment: 18 pages, 17 figures. Accepted for publication in MNRA

High Resolution Images of Orbital Motion in the Trapezium Cluster: First Scientific Results from the MMT Deformable Secondary Mirror Adaptive Optics System

We present the first scientific images obtained with a deformable secondary mirror adaptive optics system. We utilized the 6.5m MMT AO system to produce high-resolution (FWHM=0.07'') near infrared (1.6 um) images of the young (~1 Myr) Orion Trapezium theta 1 Ori cluster members. A combination of high spatial resolution and high signal to noise allowed the positions of these stars to be measured to within ~0.003'' accuracies. Including previous speckle data (Weigelt et al. 1999), we analyze a six year baseline of high-resolution observations of this cluster. Over this baseline we are sensitive to relative proper motions of only ~0.002''/yr (4.2 km/s at 450 pc). At such sensitivities we detect orbital motion in the very tight theta 1 Ori B2B3 (52 AU separation) and theta 1 Ori A1A2 (94 AU separation) systems. Such motions are consistent with those independently observed by Schertl et al. (2003) with speckle interferometry, giving us confidence that these very small (~0.002''/yr) orbital motions are real. All five members of the theta 1 Ori B system appear likely gravitationally bound. The very lowest mass member of the theta 1 Ori B system (B4) has K' ~11.66 and an estimated mass of ~0.2 Msun. There was very little motion (4+/-15 km/s) detected of B4 w.r.t B1 or B2, hence B4 is possibly part of the theta 1 Ori B group. We suspect that if this very low mass member is physically associated it most likely is in an unstable (non-hierarchical) orbital position and will soon be ejected from the group. The theta 1 Ori B system appears to be a good example of a star formation ``mini-cluster'' which may eject the lowest mass members of the cluster in the near future. This ``ejection'' process could play a major role in the formation of low mass stars and brown dwarfs.Comment: To appear in the December 10, 2003 issue of the Astrophysical Journal 21 pages, 14 figures (some in color, but print OK in B&W

SOUL at LBT: commissioning results, science and future

The SOUL systems at the Large Bincoular Telescope can be seen such as precursor for the ELT SCAO systems, combining together key technologies such as EMCCD, Pyramid WFS and adaptive telescopes. After the first light of the first upgraded system on September 2018, going through COVID and technical stops, we now have all the 4 systems working on-sky. Here, we report about some key control improvements and the system performance characterized during the commissioning. The upgrade allows us to correct more modes (500) in the bright end and increases the sky coverage providing SR(K)>20% with reference stars G$_{RP}$<17, opening to extragalcatic targets with NGS systems. Finally, we review the first astrophysical results, looking forward to the next generation instruments (SHARK-NIR, SHARK-Vis and iLocater), to be fed by the SOUL AO correction.Comment: 13 pages, 10 figures, Adaptive Optics for Extremely Large Telescopes 7th Edition, 25-30 Jun 2023 Avignon (France

SHARK-NIR, the coronagraphic camera for LBT, moving toward construction

SHARK-NIR is one of the two coronagraphic instruments proposed for the Large Binocular Telescope. Together with SHARK-VIS (performing coronagraphic imaging in the visible domain), it will offer the possibility to do binocular observations combining direct imaging, coronagraphic imaging and coronagraphic low resolution spectroscopy in a wide wavelength domain, going from 0.5{\mu}m to 1.7{\mu}m. Additionally, the contemporary usage of LMIRCam, the coronagraphic LBTI NIR camera, working from K to L band, will extend even more the covered wavelength range. In January 2017 SHARK-NIR underwent a successful final design review, which endorsed the instrument for construction and future implementation at LBT. We report here the final design of the instrument, which foresees two intermediate pupil planes and three focal planes to accomodate a certain number of coronagraphic techniques, selected to maximize the instrument contrast at various distances from the star. Exo-Planets search and characterization has been the science case driving the instrument design, but the SOUL upgrade of the LBT AO will increase the instrument performance in the faint end regime, allowing to do galactic (jets and disks) and extra-galactic (AGN and QSO) science on a relatively wide sample of targets, normally not reachable in other similar facilities.Comment: 8 pages, 6 figures, AO4ELT5 conference proceeding

SHARK-NIR: from K-band to a key instrument, a status update

SHARK-NIR channel is one of the two coronagraphic instruments proposed for the Large Binocular Telescope, in the framework of the call for second generation instruments, issued in 2014. Together with the SHARK-VIS channel, it will offer a few observing modes (direct imaging, coronagraphic imaging and coronagraphic low resolution spectroscopy) covering a wide wavelength domain, going from 0.5μm to 1.7μm. Initially proposed as an instrument covering also the K-band, the current design foresees a camera working from Y to H bands, exploiting in this way the synergy with other LBT instruments such as LBTI, which is actually covering wavelengths greater than L' band, and it will be soon upgraded to work also in K band. SHARK-NIR has been undergoing the conceptual design review at the end of 2015 and it has been approved to proceed to the final design phase, receiving the green light for successive construction and installation at LBT. The current design is significantly more flexible than the previous one, having an additional intermediate pupil plane that will allow the usage of coronagraphic techniques very efficient in term of contrast and vicinity to the star, increasing the instrument coronagraphic performance. The latter is necessary to properly exploit the search of giant exo-planets, which is the main science case and the driver for the technical choices of SHARK-NIR. We also emphasize that the LBT AO SOUL upgrade will further improve the AO performance, making possible to extend the exo-planet search to target fainter than normally achieved by other 8-m class telescopes, and opening in this way to other very interesting scientific scenarios, such as the characterization of AGN and Quasars (normally too faint to be observed) and increasing considerably the sample of disks and jets to be studied. Finally, we emphasize that SHARK-NIR will offer XAO direct imaging capability on a FoV of about 15"x15", and a simple coronagraphic spectroscopic mode offering spectral resolution ranging from few hundreds to few thousands. This article presents the current instrument design, together with the milestones for its installation at LBT. <P /

Operation and performance of the mid-infrared camera, NOMIC, on the Large Binocular Telescope

The mid-infrared (8-13 μm) camera, NOMIC, is a critical component of the Large Binocular Telescope Interferometer search for exozodiacal light around near-by stars. It is optimized for nulling interferometry but has general capability for direct imaging, low resolution spectrometry, and Fizeau interferometry. The camera uses a Raytheon 1024x1024 Si:As IBC Aquarius array with a 30 μm pitch which yields 0.018 arc-second pixels on the sky. This provides spatial resolution (λ/D) at a 10 μm wavelength of 0.27 arc-seconds for a single 8.4 meter LBT aperture and of 0.10 arcseconds for Fizeau interferometry with the dual apertures. The array is operated with a differential preamplifier and a version of the 16 channel array controller developed at Cornell University for the FORCAST instrument on the Sofia Observatory. With a 2.4 MHz pixel rate the camera can achieve integration times as short as 27 milliseconds full array and 3 milliseconds partial array. The large range of integration times and two array integration well sizes allow for a wide range of background flux on the array. We describe the design and operation of the camera and present the performance of this system in terms of linearity, noise, quantum efficiency, image quality, and photometric sensitivity

Testing and alignment of the LBTI

The Large Binocular Telescope Interferometer (LBTI) has been developed and tested and is almost ready to be installed to LBT mount. In preparation for installation, testing of the beam combination and phasing of the system have been developed. The testing is currently in progress. The development of a telescope simulator for LBTI has allowed verification of phasing and alignment with a broad band source at 10 microns2. Vibration tests with the LBTI mounted to the LBT were carried out in July 2008, with both seismic accelerometers and an internal optical interferometric measurement. The results have allowed identification of potential vibration sources on the telescope. Plans for a Star Simulator that illuminates each LBT aperture at the prime focus with two artificial point sources derived from a single point source via fiber optics are presented. The Star Simulator will allow testing of LBTI with the telescope and the adaptive secondaries in particular. Testing with the Star Simulator will allow system level testing of LBTI on the telescope, without need to use on-sky time. Testing of the Star Simulator components are presented to verify readiness for use with the LBTI.12 page(s

XAO at LBT: current performances in the visible and upcoming upgrade

The Extreme Adaptive Optics is one of the new frontiers for astronomical AO and LBT is hosting one of the few XAO systems available on 8m class telescopes. With the 4Runner, a fast visible camera, we measured the AO performances at visible wavelengths. We were able to correct up to 500 modes at 1kHz of framerate, reaching Strehl ratios of about 40% at 630nm of wavelength. We will show the results obtained in daytime with the calibration source and on-sky using natural guidestars. These performances have been obtained at the LBTI-DX focus, one of the 4 LBT focal stations equipped with a SCAO system. All these 4 systems will be upgraded in the framework of the SOUL project. The wavefront sensor detectors will be substituted with low readout noise ones, the adaptive secondary firmware and the AO control both improved. We will briefly describe here SOUL and its performances as estimated via numerical simulations

XAO at LBT: current performances in the visible and upcoming upgrade

The Extreme Adaptive Optics is one of the new frontiers for astronomical AO and LBT is hosting one of the few XAO systems available on 8m class telescopes. With the 4Runner, a fast visible camera, we measured the AO performances at visible wavelengths. We were able to correct up to 500 modes at 1kHz of framerate, reaching Strehl ratios of about 40% at 630nm of wavelength. We will show the results obtained in daytime with the calibration source and on-sky using natural guidestars. These performances have been obtained at the LBTI-DX focus, one of the 4 LBT focal stations equipped with a SCAO system. All these 4 systems will be upgraded in the framework of the SOUL project. The wavefront sensor detectors will be substituted with low readout noise ones, the adaptive secondary firmware and the AO control both improved. We will briefly describe here SOUL and its performances as estimated via numerical simulations