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We have designed and implemented a novel way to process wide-field astronomical data within a distributed environment of hardware resources and humanpower. The system is characterized by integration of archiving, calibration, and…

Instrumentation and Methods for Astrophysics · Physics 2011-10-17 J. P. McFarland , G. Verdoes-Kleijn , G. Sikkema , E. M. Helmich , D. R. Boxhoorn , E. A. Valentijn

Predictive wavefront control is an important and rapidly developing field of adaptive optics (AO). Through the prediction of future wavefront effects, the inherent AO system servo-lag caused by the measurement, computation, and application…

Instrumentation and Methods for Astrophysics · Physics 2021-03-12 Robin Swanson , Masen Lamb , Carlos Correia , Suresh Sivanandam , Kiriakos Kutulakos

ARGOS is the laser guide star ground layer adaptive optics system of the LBT. ARGOS is designed to bring a moderate but uniform reduction of the PSF size over a FoV as large as 4x4arcmin, allowing a significative increase of the science…

Instrumentation and Methods for Astrophysics · Physics 2012-03-23 Marco Bonaglia

Ground-based high contrast exoplanet imaging requires state-of-the-art adaptive optics (AO) systems in order to detect extremely faint planets next to their brighter host stars. For such extreme AO systems (with high actuator count…

Earth and Planetary Astrophysics · Physics 2022-08-02 J. Fowler , Maaike A. M. Van Kooten , Rebecca Jensen-Clem

The sodium laser guide star adaptive optics system ALFA, which is installed at the Calar Alto 3.5-m telescope, has been undergoing an intensive optimisation phase. Observations using natural guide stars that are presented in this paper,…

Astrophysics · Physics 2007-05-23 R. I. Davies , W. Hackenberg , T. Ott , A. Eckart , S. Rabien , S. Anders , S. Hippler , M. Kaspar

We have done theoretical calculations and simulations for infrared spectroscopy at the MMT 6.5 m with laser guide star AO, which provides almost full sky coverage. The results show we can expect 40-60% of the photons from a unresolved…

Astrophysics · Physics 2015-06-24 Jian Ge , Roger Angel , David Sandler , Chris Shelton , Don McCarthy , Jim Burge

A multi-object spectrograph on the forthcoming European Extremely Large Telescope will be required to operate with good sky coverage. Many of the interesting deep cosmological fields were deliberately chosen to be free of bright foreground…

Instrumentation and Methods for Astrophysics · Physics 2015-06-23 Alastair Basden , Chris Evans , Tim Morris

Laser Guide Stars (LGS) have greatly increased the sky-coverage of Adaptive Optics (AO) systems. Due to the up-link turbulence experienced by LGSs, a Natural Guide Star (NGS) is still required, preventing full sky-coverage. We present a…

Instrumentation and Methods for Astrophysics · Physics 2016-03-23 A. P. Reeves , T. J. Morris , R. M. Myers , N. A. Bharmal , J. Osborn

The direct imaging and characterization of exoplanets requires extreme adaptive optics (XAO), achieving exquisite wavefront correction (upwards of 90$\%$ Strehl) over a narrow field of view (a few arcseconds). For these XAO systems the…

Instrumentation and Methods for Astrophysics · Physics 2024-07-17 J. Fowler , Rebecca Jensen-Clem , Maaike A. M. van Kooten , Vincent Chambouleyron , Sylvain Cetre

Both lucky imaging techniques and adaptive optics require natural guide stars, limiting sky coverage, even when laser guide stars are used. Lucky imaging techniques become less successful on larger telescopes unless adaptive optics is used,…

Instrumentation and Methods for Astrophysics · Physics 2015-06-19 Alastair Basden

Adaptive optics (AO) is critical in astronomy, optical communications and remote sensing to deal with the rapid blurring caused by the Earth's turbulent atmosphere. But current AO systems are limited by their wavefront sensors, which need…

Instrumentation and Methods for Astrophysics · Physics 2020-10-23 Barnaby R. M. Norris , Jin Wei , Christopher H. Betters , Alison Wong , Sergio G. Leon-Saval

Over the last few years increasing consideration has been given to the study of Laser Guide Stars (LGS) for the measurement of the disturbance introduced by the atmosphere in optical and near-infrared astronomical observations from the…

Instrumentation and Methods for Astrophysics · Physics 2015-05-13 L. Schreiber , I. Foppiani , C. Robert , E. Diolaiti , J. -M. Conan , M. Lombini

We present the Wavefront Sensor units of the Gravity Plus Adaptive Optics (GPAO) system, which will equip all 8m class telescopes of the VLTI and is an instrumental part of the GRAVITY+ project. It includes two modules for each Wavefront…

The integral field spectrograph configuration of the LMIRCam science camera within the Large Binocular Telescope Interferometer (LBTI) facilitates 2 to 5 $\mu$m spectroscopy of directly imaged gas-giant exoplanets. The mode, dubbed ALES,…

Instrumentation and Methods for Astrophysics · Physics 2018-08-09 Jordan M. Stone , Andrew J. Skemer , Philip Hinz , Zack Briesemeister , Travis Barman , Charles E. Woodward , Mike Skrutskie , Jarron Leisenring

We present a promising approach to the extremely fast sensing and correction of small wavefront errors in adaptive optics systems. As our algorithm's computational complexity is roughly proportional to the number of actuators, it is…

Instrumentation and Methods for Astrophysics · Physics 2016-11-26 Christoph U. Keller , Visa Korkiakoski , Niek Doelman , Rufus Fraanje , Raluca Andrei , Michel Verhaegen

We present two estimators to quantify the angular power spectrum of the sky signal directly from the visibilities measured in radio interferometric observations. This is relevant for both the foregrounds and the cosmological 21-cm signal…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-11 Samir Choudhuri , Somnath Bharadwaj , Abhik Ghosh , SK. Saiyad Ali

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

Context. Late O-type stars at luminosities $\log L/L_\odot \lesssim 5.2$ show weak winds with mass-loss rates lower than 10$^{-8} M_\odot$ yr$^{-1}$. This implies that their photospheric layers are not strongly affected by the stellar wind.…

Solar and Stellar Astrophysics · Physics 2023-03-08 Patrick Aschenbrenner , Norbert Przybilla , Keith Butler

The advent of a new generation of Adaptive Optics systems called Wide Field AO (WFAO) mark the beginning of a new era. By using multiple Guide Stars (GSs), either Laser Guide Stars (LGSs) or Natural Guide Stars (NGSs), WFAO significantly…

Instrumentation and Methods for Astrophysics · Physics 2015-06-22 Benoit Neichel , Elena Masciadri , Andrés R. Guesalaga , Franck Lascaux , Clémentine Béchet

HARMONI is the first light visible and near-IR integral field spectrograph for the ELT. It covers a large spectral range from 470nm to 2450nm with resolving powers from 3300 to 18000 and spatial sampling from 60mas to 4mas. It can operate…

Instrumentation and Methods for Astrophysics · Physics 2024-10-03 Eduard Muslimov , Edgar Castillo-Dominguez , James Kariuki , Jorge Chao-Ortiz , Matthias Tecza , Elliot Meyer , Zeynep Ozer , Fraser Clarke , Niranjan Thatte