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We present the first results from our high-precision infrared (IR) astrometry program at the Canada-France-Hawaii Telescope. We measure parallaxes for 83 ultracool dwarfs (spectral types M6--T9) in 49 systems, with a median uncertainty of…

Solar and Stellar Astrophysics · Physics 2015-06-03 Trent J. Dupuy , Michael C. Liu

Photonic technologies offer numerous advantages for astronomical instruments such as spectrographs and interferometers owing to their small footprints and diverse range of functionalities. Operating at the diffraction-limit, it is…

Instrumentation and Methods for Astrophysics · Physics 2017-08-30 N. Jovanovic , C. Schwab , O. Guyon , J. Lozi , N. Cvetojevic , F. Martinache , S. Leon-Saval , B. Norris , S. Gross , D. Doughty , T. Currie , N. Takato

`Imaka is a ground layer adaptive optics (GLAO) demonstrator on the University of Hawaii 2.2m telescope with a 24'x18' field-of-view, nearly an order of magnitude larger than previous AO instruments. In 15 nights of observing with natural…

Instrumentation and Methods for Astrophysics · Physics 2018-08-29 Fatima Abdurrahman , Jessica R. Lu , Mark Chun , Max W. Service , Olivier Lai , Dora Fohring , Doug Toomey , Christoph Baranec

One important frontier for astronomical adaptive optics (AO) involves methods such as Multi-Object AO and Multi-Conjugate AO that have the potential to give a significantly larger field of view than conventional AO techniques. A second key…

Instrumentation and Methods for Astrophysics · Physics 2015-05-13 S. Mark Ammons , Luke Johnson , Edward A. Laag , Renate Kupke , Donald T. Gavel , Brian J. Bauman , Claire E. Max

We present adaptive optics imaging of the CLASS gravitational lens system B1359+154 obtained with the Canada-France-Hawaii Telescope (CFHT) in the infrared K band. The observations show at least three brightness peaks within the ring of…

Astrophysics · Physics 2009-10-31 D. Rusin , P. B. Hall , R. C. Nichol , D. R. Marlow , A. M. S. Richards , S. T. Myers

We review astronomical results in the visible (lambda <1 micron) with adaptive optics and note the status the MagAO system and the recent upgrade to visible camera's Simultaneous/Spectra Differential Imager (SDI to SDI+) mode. Since…

The efficiency of the management of top-class ground-based astronomical facilities supported by Adaptive Optics (AO) relies on our ability to forecast the optical turbulence (OT) and a set of relevant atmospheric parameters. Indeed, in…

Instrumentation and Methods for Astrophysics · Physics 2020-06-14 E. Masciadri , G. Martelloni , A. Turchi

Quantitative information about variations in the background at J and K' are presented and used to develop guidelines for the acquisition and reduction of ground-based images of faint extended sources in the near-infrared, especially those…

Astrophysics · Physics 2009-11-10 Ovidiu Vaduvescu , Marshall L. McCall

Accurate and precise measurements of the Hubble constant are critical for testing our current standard cosmological model and revealing possibly new physics. With Hubble Space Telescope (HST) imaging, each strong gravitational lens system…

The MCAO Assisted Visible Imager and Spectrograph (MAVIS) is a new visible instrument for ESO Very Large Telescope (VLT). Its Adaptive Optics Module (AOM) must provide extreme adaptive optics correction level at low galactic latitude and…

Instrumentation and Methods for Astrophysics · Physics 2022-09-01 Guido Agapito , Daniele Vassallo , Cédric Plantet , Jesse Cranney , Hao Zhang , Valentina Viotto , Enrico Pinna , Francois Rigaut

Adaptive Optics (AO) is an innovative technique that substantially improves the optical performance of ground-based telescopes. The SOAR Adaptive Module (SAM) is a laser-assisted AO instrument, designed to compensate ground-layer…

Instrumentation and Methods for Astrophysics · Physics 2018-08-28 D. M. Faes , A. Tokovinin , T. Vieira , A. Mello , M. Domingues , D. Andrade , B. C. Quint , J. B. Santos

We demonstrate for the first time an efficient, photonic-based astronomical spectrograph on the 8-m Subaru Telescope. An extreme adaptive optics system is combined with pupil apodiziation optics to efficiently inject light directly into a…

Instrumentation and Methods for Astrophysics · Physics 2017-08-29 N. Jovanovic , N. Cvetojevic , B. Norris , C. Betters , C. Schwab , J. Lozi , O. Guyon , S. Gross , F. Martinache , P. Tuthill , D. Doughty , Y. Minowa , N. Takato , J. Lawrence

From natural guide star adaptive optics data taken with the Come-On Plus and with the Starfire Optical Range Generation II instruments in the JHK bands and in the I band respectively, we describe and analyse the point spread function. The…

Astrophysics · Physics 2015-06-24 Eric Tessier

The next generation of extreme adaptive optics (AO) must be calibrated exceptionally well to achieve the desired contrast for ground-based direct imaging exoplanet targets. Current wavefront sensing and control system responses deviate from…

Astrometric precision and knowledge of the point spread function are key ingredients for a wide range of astrophysical studies including time-delay cosmography in which strongly lensed quasar systems are used to determine the Hubble…

Instrumentation and Methods for Astrophysics · Physics 2021-09-22 Geoff C. -F. Chen , Tommaso Treu , Christopher D. Fassnacht , Sam Ragland , Thomas Schmidt , Sherry H. Suyu

The EAGLE instrument for the E-ELT is a multi-IFU spectrograph, that uses a MOAO system for wavefront correction of interesting lines of sight. We present a Monte-Carlo AO simulation package that has been used to model the performace of…

Instrumentation and Methods for Astrophysics · Physics 2018-08-29 Alastair Basden , Timothy Butterley , Richard Myers

Atmospheric profiling is a requirement for controlling wide-field Adaptive Optics (AO) instruments, analyzing the AO performance with respect to the observing conditions and predicting the Point Spread Function (PSF) spatial variations. We…

Instrumentation and Methods for Astrophysics · Physics 2019-04-17 Olivier Beltramo-Martin , Nazim A. Bharmal , Carlos M. Correia

We summarize the theory of coronagraphic optics, and identify a dimensionless fine-tuning parameter, F, which we use to describe the Lyot stop size in the natural units of the coronagraphic optical train and the observing wavelength. We…

Astrophysics · Physics 2009-11-06 A. Sivaramakrishnan , C. D. Koresko , R. B. Makidon , T. Berkefeld , M. J. Kuchner

Underwater optical imaging is severely degraded by light absorption, scattering, and color distortion, hindering visibility and accurate image analysis. This paper presents an adaptive enhancement framework integrating illumination…

Computer Vision and Pattern Recognition · Computer Science 2025-03-06 Yuezhe Tian , Kangchen Yao , Xiaoyang Yu

The optimization and scheduling of scientific observations done with instrumentation supported by adaptive optics could greatly benefit from the forecast of PSF figures of merit (FWHM, Strehl Ratio, Encircle Energy and contrast), that…

Instrumentation and Methods for Astrophysics · Physics 2020-12-15 A. Turchi , G. Agapito , E. Masciadri , O. Beltramo-Martin , E. Pinna , J. F. Sauvage , T. Fusco , B. Neichel , J. Milli