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Related papers: Speckle Imaging with VLT/NACO No-AO Mode

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Future large space telescopes will be equipped with adaptive optics (AO) to overcome wavefront aberrations and achieve high contrast for imaging faint astronomical objects, such as earth-like exoplanets and debris disks. In contrast to AO…

Instrumentation and Methods for Astrophysics · Physics 2020-01-07 He Sun , N. Jeremy Kasdin , Robert Vanderbei

Rather than using an adaptive optics (AO) system to correct a telescope s entire pupil, it can instead be used to more finely correct a smaller sub-aperture. Indeed, existing AO systems can be used to correct a sub-aperture 1/3 to 1/2 the…

Astrophysics · Physics 2009-11-13 E. Serabyn , K. Wallace , M. Troy , B. Mennesson , P. Haguenauer , R. Gappinger , R. Burruss

Extreme adaptive optics systems are now in operation across the globe. These systems, capable of high order wavefront correction, deliver Strehl ratios of 90% in the near-infrared. Originally intended for the direct imaging of exoplanets,…

Instrumentation and Methods for Astrophysics · Physics 2016-11-09 Nemanja Jovanovic , Christian Schwab , Nick Cvetojevic , Olivier Guyon , Frantz Martinache

Speckle imaging is a well known method to achieve diffraction-limited (DL) imaging from ground-based telescopes. The traditional observing method for speckle has been to observe a single, unresolved, source per telescope pointing over a…

Instrumentation and Methods for Astrophysics · Physics 2018-06-04 James W. Davidson , Elliott P. Horch , Steven R. Majewski

Holographic optical coherence tomography (OCT) is a powerful imaging technique, but its ability to reveal low-reflectivity features is limited. In this study, we performed holographic OCT by incoherently averaging volumes with changing…

The present `state of the art' and the path to future progress in high spatial resolution imaging interferometry is reviewed. The review begins with a treatment of the fundamentals of stellar optical interferometry, the origin, properties,…

Astrophysics · Physics 2008-11-26 Swapan K Saha

The contemporary astronomy is flooded with an exponentially growing petabyte-scaled data volumes produced by powerful ground and space-based instrumentation as well as a product of extensive computer simulations and computations of complex…

Instrumentation and Methods for Astrophysics · Physics 2018-03-14 Petr Škoda

Resolving fine details of astronomical objects provides critical insights into their underlying physical processes. This drives in part the desire to construct ever-larger telescopes and interferometer arrays and to observe at shorter…

Using an observational derived model optical turbulence profile (model-OTP) we have investigated the performance of Adaptive Optics (AO) at Siding Spring Observatory (SSO), Australia. The simulations cover the performance for AO techniques…

Instrumentation and Methods for Astrophysics · Physics 2015-06-11 Michael Goodwin , Charles Jenkins , Andrew Lambert

We report on the results of calibrating and simulating the instrumental polarization properties of the ESO VLT adaptive optics camera system NAOS/CONICA (NACO) in the Ks-band. We use the Stokes/Mueller formalism for metallic reflections to…

Instrumentation and Methods for Astrophysics · Physics 2015-05-20 G. Witzel , A. Eckart , R. M. Buchholz , M. Zamaninasab , R. Lenzen , R. Schödel , C. Araujo , N. Sabha , M. Bremer , V. Karas , C. Straubmeier , K. Muzic

Light-based synthetic aperture (SA) imaging methods, such as Fourier Ptychography, have brought breakthrough high-resolution wide-field-of-view imaging capabilities to microscopy. While these technologies promise similar improvements in…

Optics · Physics 2025-09-29 Janith B. Senanayaka , Christopher A. Metzler

Using five independent analytic and Monte Carlo simulation codes, we have studied the performance of wide field ground layer adaptive optics (GLAO), which can use a single, relatively low order deformable mirror to correct the wavefront…

We previously demonstrated near-field speckle scanning based x-ray imaging to be an easy-to-implement phase sensing method capable of providing both high sensitivity and high resolution. Yet, this performance combination could only be…

Medical Physics · Physics 2017-06-21 Sebastien Berujon , Eric Ziegler

The next generation of large ground-based optical and infrared telescopes will provide new challenges for designers of astronomical instrumentation. The varied science cases for these extremely large telescopes (ELTs) require a large range…

Astrophysics · Physics 2009-11-13 Colin Cunningham , Chris Evans , Guy Monnet , Miska Le Louarn

The development of adaptive optics (AO) played a major role in modern astronomy over the last three decades. By compensating for the atmospheric turbulence, these systems enable to reach the diffraction limit on large telescopes. In this…

Instrumentation and Methods for Astrophysics · Physics 2017-01-05 Julien Milli , Dimitri Mawet , David Mouillet , Markus Kasper , Julien H. Girard

Angular differential imaging (ADI) (Marois et al. 2006) is an observational technique in high contrast imaging where the telescope is used in pupil tracking mode so that the image of the sky rotates with respect to the optical surfaces.…

Earth and Planetary Astrophysics · Physics 2017-11-28 Michael Bottom , Garreth Ruane , Dimitri Mawet

Radial velocity instruments require high spectral resolution and extreme thermo-mecanical stability, even more difficult to achieve in near-infra red (NIR) where the spectrograph has to be cooled down. For a seeing-limited spectrograph, the…

Instrumentation and Methods for Astrophysics · Physics 2016-11-23 Uriel Conod , Nicolas Blind , François Wildi , Francesco Pepe

Speckle is an intrinsic pattern in optical coherence tomography (OCT) that obscures fine image features and degrades effective resolution. In this study, we propose a numerical speckle reduction method based on the dispersed scatterer model…

In this paper, we present a first comparison of different Adaptive Optics (AO) concepts to reach a given scientific specification for 3D spectroscopy on Extremely Large Telescope (ELT). We consider that a range of 30%-50% of Ensquarred…

(Abridged) Lunar occultations (LO) are a very efficient and powerful technique, that achieves the best combination of high angular resolution and sensitivity possible today at near-infrared wavelengths. Given that the events are fixed in…

Solar and Stellar Astrophysics · Physics 2015-05-19 A. Richichi , O. Fors , W-P. Chen , E. Mason