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New high-resolution adaptive optics systems provide an unprecedentedly detailed view of nearby star forming regions. In particular, young nearby T Tauri stars can be probed at much smaller physical scales (a few AU) than possible just a…

Astrophysics · Physics 2007-05-23 Alexis Brandeker

Large area surveys will dominate the next decade of astronomy, and the main limitation to science will be the thorough followup and characterization of their extremely numerous discoveries. The deployment of robotic laser adaptive optics on…

Instrumentation and Methods for Astrophysics · Physics 2019-07-17 Christoph Baranec

The sensitivity of stellar spectra to alpha/Fe abundance changes is investigated with the aim to be detected photometricly and employed for scientific goals of the GAIA mission. A grid of plane parallel, line blanketed, flux constant, LTE…

Astrophysics · Physics 2009-11-07 Grazina Tautvaisiene , Bengt Edvardsson

Even though the technology of adaptive optics (AO) is rapidly maturing, calibration of the resulting images remains a major challenge. The AO point-spread function (PSF) changes quickly both in time and position on the sky. In a typical…

Precision wavefront control on future segmented-aperture space telescopes presents significant challenges, particularly in the context of high-contrast exoplanet direct imaging. We present a new wavefront control architecture that…

Instrumentation and Methods for Astrophysics · Physics 2019-01-08 Ewan S. Douglas , Jared R. Males , James Clark , Olivier Guyon , Jennifer R. Lumbres , Weston A. Marlow , Kerri L. Cahoy

Robo-AO is the first astronomical laser guide star adaptive optics (AO) system designed to operate completely independent of human supervision. A single computer commands the AO system, the laser guide star, visible and near-infrared…

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

The performance of adaptive optics systems is partially dependant on the algorithms used within the real-time control system to compute wavefront slope measurements. We demonstrate use of a matched filter algorithm for the processing of…

As new large-scale astronomical surveys greatly increase the number of objects targeted and discoveries made, the requirement for efficient follow-up observations is crucial. Adaptive optics imaging, which compensates for the image-blurring…

The WHT is unusually well-placed for exploitation of adaptive-optics (AO) technology. The site seeing is excellent (median 0.7 arcsec), dome seeing is negligible, and preliminary studies indicate that most of the atmospheric seeing…

Astrophysics · Physics 2009-11-06 C. R. Benn

The major cornerstone of future ground-based astronomy is imaging and spectroscopy at the diffraction limit using adaptive optics. To exploit the potential of current AO systems, we have begun a survey around bright stars to study…

Astrophysics · Physics 2007-05-23 R. I. Davies , M. Lehnert , A. J. Baker , S. Rabien

We describe several projects addressing the growth of galaxies and massive black holes, for which adaptive optics is mandatory to reach high spatial resolution but is also a challenge due to the lack of guide stars and long integrations. In…

Instrumentation and Methods for Astrophysics · Physics 2015-05-19 Richard Davies , Hauke Engel , Erin Hicks , Natascha Foerster Schreiber , Reinhard Genzel , Linda Tacconi , Frank Eisenhauer , Sebastian Rabien

Sky-coverage in laser-assisted AO observations largely depends on the system's capability to guide on the faintest natural guide-stars possible. Here we give an up-to-date status of our natural guide-star processing tailored to the…

Instrumentation and Methods for Astrophysics · Physics 2016-11-23 Carlos M. Correia , Benoit Neichel , Jean-Marc Conan , Cyril Petit , Jean-Francois Sauvage , Thierry Fusco , Joel D. R. Vernet , Niranjan Thatte

ALMA will revolutionize the study of star formation by providing a combination of angular resolution and sensitivity that far exceeds that of present instruments. I will focus on studies of relatively isolated cores that are forming…

Astrophysics · Physics 2007-05-23 Neal J. Evans

Optical interferometry provides us with a unique opportunity to improve our understanding of stellar structure and evolution. Through direct observation of rotationally distorted photospheres at sub-milliarcsecond scales, we are now able to…

Solar and Stellar Astrophysics · Physics 2012-04-13 Gerard T. van Belle

Pulsed sodium laser guide stars (LGS) are useful because they allow for Rayleigh blanking and fratricide avoidance in multiple-LGS systems. Bloch-equation simulations of sodium-light interactions show that these may be able to achieve…

Instrumentation and Methods for Astrophysics · Physics 2023-07-19 Rachel Rampy , Donald Gavel , Simon M. Rochester , Ronald Holzlohner

Adaptive optics (AO) is a key technology for ground-based optical and infrared astronomy, providing high angular resolution and sensitivity. AO systems employing laser guide stars (LGS) can achieve high sky coverage, but their performance…

Instrumentation and Methods for Astrophysics · Physics 2021-04-21 P. Hickson , J. Hellemeier , R. Yang

We have used laser guide star adaptive optics and a near-infrared dual-channel imaging polarimeter to observe light scattered in the circumstellar environment of Herbig Ae/Be stars on scales of 100-300 AU. We discover a strongly polarized,…

(35-words maximum) In this talk I present the scientific drivers related to the optical turbulence forecast applied to the ground-based astronomy supported by Adaptive Optics, the state of the art of the achieved results and the most…

Instrumentation and Methods for Astrophysics · Physics 2019-02-22 Elena Masciadri , Alessio Turchi , Luca Fini

The ALEPH Silicon Vertex Detector features an optical fibre laser system to monitor its mechanical stability. The operating principle and the general performance of the laser system are described. The experience obtained during 1997 and…

Instrumentation and Detectors · Physics 2019-08-14 G. Sguazzoni