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Lorentz transmission electron microscopy (LTEM) is a powerful tool for high-resolution imaging of magnetic textures, including their dynamics under external stimuli and ultrafast nonequilibrium conditions. However, magnetic imaging is often…

Materials Science · Physics 2025-05-12 Shunsuke Hayashi , Dongxue Han , Hidenori Tsuji , Kyoko Ishizaka , Asuka Nakamura

The EAGLE and EVE Phase A studies for instruments for the European Extremely Large Telescope (E-ELT) originated from related top-level scientific questions, but employed different (yet complementary) methods to deliver the required…

LOFT (Large Observatory For x-ray Timing) is one of the four missions selected in 2011 for assessment study for the ESA M3 mission in the Cosmic Vision program, expected to be launched in 2024. The LOFT mission will carry two instruments…

HIRES, a high resolution spectrometer, is one of the first five instruments foreseen in the ESO roadmap for the E-ELT. This spectrograph should ideally provide full spectral coverage from the UV limit to 2.5 microns, with a resolving power…

Instrumentation and Methods for Astrophysics · Physics 2015-06-22 N. Sanna , E. Oliva , F. Massi , G. Cresci , L. Origlia

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

A breakthrough in the sensitivity level of the hard X-/gamma-ray telescopes, which today are based on detectors that view the sky through (or not) coded masks, is expected when focusing optics will be available also in this energy range.…

Speckle Noise is the dominant source of error in high contrast imaging with adaptive optics system. We discuss the potential for wavefront sensing telemetry to calibrate speckle noise with sufficient precision and accuracy so that it can be…

We use telemetry data from the Gemini North ALTAIR adaptive optics system to investigate how well the commands for wavefront correction (both Tip/Tilt and high-order turbulence) can be forecasted in order to reduce lag error (due to…

Instrumentation and Methods for Astrophysics · Physics 2022-05-16 Rehan Hafeez , Finn Archinuk , Sébastien Fabbro , Hossen Teimoorinia , Jean-Pierre Véran

PULSE is a new concept to augment the currently operating 5.1-m Hale PALM-3000 exoplanet adaptive optics system with an ultraviolet Rayleigh laser and associated wavefront sensor. By using an ultraviolet laser to measure the high spatial…

Instrumentation and Methods for Astrophysics · Physics 2013-09-18 Christoph Baranec , Richard Dekany , Marcos van Dam , Rick Burruss

The EAGLE instrument is a Multi-Object Adaptive Optics (MOAO) fed, multiple Integral Field Spectrograph (IFS), working in the Near Infra-Red (NIR), on the European Extremely Large Telescope (E-ELT). A Phase A design study was delivered to…

In this paper, super-focusing using radiationless electromagnetic interference is extended to the visible regime. It is shown that the highest-order mode of a specifically designed metal-dielectric waveguide array can provide the rapidly…

Optics · Physics 2008-11-11 Reuven Gordon

High-contrast imaging will be a challenge for future ELTs, because their vibrations create low-order aberrations - mostly tip/tilt - that reduce coronagraphic performances at 1.2 lambda/D and above. A Low-Order WaveFront Sensor (LOWFS) is…

Instrumentation and Methods for Astrophysics · Physics 2015-06-17 Julien Lozi , Ruslan Belikov , Glenn Schneider , Olivier Guyon , EugenePluzhnik , Sandrine J. Thomas , Frantz Martinache

The European Extremely Large Telescope will see first lights by the end of 2024. With a diameter of almost 40 meters, it will be the biggest optical telescope ever built from the ground. The ELT will open a brand new window in a sensitivity…

Instrumentation and Methods for Astrophysics · Physics 2018-12-18 B. Neichel , D. Mouillet , E. Gendron , C. Correia , J. F. Sauvage , T. Fusco

Sodium Laser Guide Stars (LGSs) are elongated sources due to the thickness and the finite distance of the sodium layer. The fluctuations of the sodium layer altitude and atom density profile induce errors on centroid measurements of…

Instrumentation and Methods for Astrophysics · Physics 2015-05-13 Olivier Lardiere , Rodolphe Conan , Colin Bradley , Kate Jackson , Peter Hampton

We proposed that the European ELT will be equipped with an ultra-high-precision polarimetric light feed as part of its high resolution optical and near-IR spectrograph HIRES. Such a feed is unique among the new ELTs and only possible in a…

Instrumentation and Methods for Astrophysics · Physics 2019-04-11 Klaus G. Strassmeier

In the context of the LAUE project devoted to build a long focal length focusing optics for soft gamma-ray astronomy (70/100 keV to $>$600 keV), we present results of simulation of a Laue lens, based on bent crystals in different assembling…

Instrumentation and Methods for Astrophysics · Physics 2015-06-12 Vineeth Valsan , Filippo Frontera , Enrico Virgilli , Vincenzo Liccardo

We demonstrate a tandem lens optical setup, comprising two diffractive optics, that focuses a high-power ultrafast laser with a shaped on-axis intensity profile, producing a meter-long Bessel focus. The intended use of the optical setup is…

Optics · Physics 2025-09-03 R. Ariniello , V. Lee , M. D. Litos

In previous works we presented a novel multiparametric sensor to simultaneously measure the refractive index and the speed of sound in a liquid by means of the acousto-optic effect. The sensor requires an illumination system that expands…

Optics · Physics 2024-06-05 Patricia María Elena Vázquez , Germán Eduardo Caro

Q-LET is a FORTRAN 77 code that enables a quick estimate of the gravitational lensing effects on a point- or an extended source. The user provided input consists of the redshifts, angular positions relative to the source, mass or velocity…

Astrophysics · Physics 2009-11-10 Christofer Gunnarsson

Transformers have had tremendous impact for several sequence related tasks, largely due to their ability to retrieve from any part of the sequence via softmax based dot-product attention. This mechanism plays a crucial role in Transformer's…

Machine Learning · Computer Science 2025-07-15 Sai Surya Duvvuri , Inderjit S. Dhillon
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