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Related papers: Forecasting Wavefront Corrections in an Adaptive O…

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Many adaptive optics systems operate by measuring the distortion of the wavefront in one wavelength range and performing the scientific observations in a second, different wavelength range. One common technique is to measure wavefront…

Astrophysics · Physics 2009-11-07 Henry G. Roe

Fourier-based wavefront sensors, such as the Pyramid Wavefront Sensor (PWFS), are the current preference for high contrast imaging due to their high sensitivity. However, these wavefront sensors have intrinsic nonlinearities that constrain…

Instrumentation and Methods for Astrophysics · Physics 2020-05-22 Rico Landman , Sebastiaan Haffert

Multi-conjugated adaptive optics (MCAO) yield nearly diffraction-limited images at 2$\mu$m wavelengths. Currently, GeMS/GSAOI at Gemini South is the only MCAO facility instrument at an 8m telescope. Using real data and for the first time,…

Instrumentation and Methods for Astrophysics · Physics 2017-09-08 Mischa Schirmer , Vincent Garrel , Gaetano Sivo , Eduardo Marin , Eleazar R. Carrasco

We propose a novel control approach that combines offline supervised learning to address the challenges posed by non-linear phase reconstruction using unmodulated pyramid wavefront sensors (P-WFS) and online reinforcement learning for…

Instrumentation and Methods for Astrophysics · Physics 2024-05-24 Bartomeu Pou , Jeffrey Smith , Eduardo Quinones , Mario Martin , Damien Gratadour

Atmospheric turbulence causes fluctuations in the local refractive index of air that accumulatively disturb a wave's phase and amplitude distribution as it propagates. This impairs the effective range of laser weapons as well as the…

Optics · Physics 2015-06-02 Chensheng Wu , Jonathan Ko , Christopher C. Davis

Time series Forecasting with large languagemodels (LLMs) requires bridging numericalpatterns and natural language. Effective fore-casting on LLM often relies on extensive pre-processing and fine-tuning.Recent studiesshow that a frozen LLM…

Computation and Language · Computer Science 2025-08-28 Gunjan Jalori , Preetika Verma , Sercan Ö Arık

We describe results from the first astronomical adaptive optics system to use multiple laser guide stars, located at the 6.5-m MMT telescope in Arizona. Its initial operational mode, ground-layer adaptive optics (GLAO), provides uniform…

Observational tests of ground layer wavefront recovery have been made in open loop using a constellation of four natural guide stars at the 1.55 m Kuiper telescope in Arizona. Such tests explore the effectiveness of wide-field seeing…

Astrophysics · Physics 2011-02-11 Christoph Baranec , Michael Lloyd-Hart , N. Mark Milton

Highly directional mmWave/THz links require rapid beam alignment, yet exhaustive codebook sweeps incur prohibitive training overhead. This letter proposes a sensing-assisted adaptive probing policy that maps multimodal sensing…

Signal Processing · Electrical Eng. & Systems 2026-03-26 Abidemi Orimogunje , Vukan Ninkovic , Ognjen Kundacina , Hyunwoo Park , Sunwoo Kim , Dejan Vukobratovic , Evariste Twahirwa , Gaspard Gashema

Diffraction limited resolution adaptive optics (AO) correction in visible wavelengths requires a high performance control. In this paper we investigate infinite impulse response filters that optimize the wavefront correction: we tested…

Instrumentation and Methods for Astrophysics · Physics 2015-06-05 G. Agapito , C. Arcidiacono , F. Quirós-Pacheco , A. Puglisi , S. Esposito

Forecast of optical turbulence and atmospheric parameters relevant for ground-based astronomy is becoming an important goal for telescope planning and AO instruments optimization in several major telescope. Such detailed and accurate…

Instrumentation and Methods for Astrophysics · Physics 2022-10-21 A. Turchi , E. Masciadri , L. Fini

The Gemini Multi-conjugate Adaptive Optics System - GeMS, a facility instrument mounted on the Gemini South telescope, delivers a uniform, near diffraction limited images at near infrared wavelengths (0.95 microns- 2.5 microns) over a field…

In the context of the GRAVITY+ upgrade, the adaptive optics (AO) systems of the GRAVITY interferometer are undergoing a major lifting. The current CILAS deformable mirrors (DM, 90 actuators) will be replaced by ALPAO kilo-DMs (43x43, 1432…

We use spatio-temporal cross-correlations of slopes from five Shack-Hartmann wavefront sensors to analyse the temporal evolution of the atmospheric turbulence layers at different altitudes. The focus is on the verification of the frozen…

Instrumentation and Methods for Astrophysics · Physics 2014-02-28 Andrés Guesalaga , Benoit Neichel , Angela Cortes , Clémentine Béchet , Dani Guzmán

Autonomous platforms require accurate positioning to complete their tasks. To this end, a Kalman filter-based algorithms, such as the extended Kalman filter or invariant Kalman filter, utilizing inertial and external sensor fusion are…

Systems and Control · Electrical Eng. & Systems 2026-03-31 Barak Diker , Itzik Klein

Adaptive Optics at mid-IR wavelengths has long been seen as either not necessary or easy. The impact of atmospheric turbulence on the performance of 8-10 meter class telescopes in the mid-IR is relatively small compared to other performance…

Instrumentation and Methods for Astrophysics · Physics 2015-05-14 R. Stuik , L. Jolissaint , S. Kendrew , S. Hippler , B. Brandl , L. Venema

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

We have designed a plenoptic sensor to retrieve phase and amplitude changes resulting from a laser beam's propagation through atmospheric turbulence. Compared with the commonly restricted domain of (-pi, pi) in phase reconstruction by…

Optics · Physics 2023-07-19 Chensheng Wu , Jonathan Ko , Christopher C. Davis

Adaptive optics (AO) system performance is improved using post-processing techniques, such as point spread function (PSF) deconvolution. The PSF estimation involves characterization of the different wavefront (WF) error sources in the AO…

Instrumentation and Methods for Astrophysics · Physics 2018-08-29 Florian Ferreira , Eric Gendron , Gérard Rousset , Damien Gratadour

In many practical applications, signals and environments are time- varying, which makes fixed filters unreliable. Adaptive filtering, on the other hand, updates in real time to suppress noise, track nonstationary signals, and identify…

General Mathematics · Mathematics 2026-03-12 Keshav Raj Acharya , Pitambar Acharya
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