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We present a novel spectroscopy protocol based on optimal control of a single quantum system. It enables measurements with quantum-limited sensitivity (\eta_\omega ~ 1/sqrt(T_2^*),T_2^* denoting the system's coherence time) but has an…

The consortium of the Spectro-Polarimetric High-contrast Exoplanet REsearch installed at the Very Large Telescope (SPHERE/VLT) has been operating its guaranteed observation time (260 nights over five years) since February 2015. The main…

Super-resolution imaging techniques enable nanoscale microscopy in fields such as physics, biology, and chemistry. However, many super-resolution techniques require specialized optical components, such as a helical-phase mask. We present a…

In this paper we illustrate the technique used by the New Vacuum Solar Telescope to increase the spatial resolution of two-dimensional (2D) solar spectroscopy observation involving two dimensions of space and one of wavelength. Without an…

Instrumentation and Methods for Astrophysics · Physics 2018-05-02 Yun-Fang Cai , Zhi Xu , Yu-Chao Chen , Jun Xu , Zheng-Gang Li , Yu Fu , Kai-Fan Ji

Photometric and astrometric monitoring of directly imaged exoplanets will deliver unique insights into their rotational periods, the distribution of cloud structures, weather, and orbital parameters. As the host star is occulted by the…

Instrumentation and Methods for Astrophysics · Physics 2020-07-01 Steven P. Bos

Space-based coronagraphs for future earth-like planet detection will require focal plane wavefront control techniques to achieve the necessary contrast levels. These correction algorithms are iterative and the control methods require an…

Instrumentation and Methods for Astrophysics · Physics 2015-06-11 Tyler D. Groff , N. Jeremy Kasdin

Nulling interferometry has been identified as a competitive technique for the detection of extrasolar planets. The technique consists in combining out-of-phase pairs of telescopes to null effectively the light of a bright star an reveal the…

Instrumentation and Methods for Astrophysics · Physics 2015-06-19 Ronny Errmann , Stefano Minardi , Lucas Labadie , Felix Dreisow , Stefan Nolte , Thomas Pertsch

Information extraction from synthetic aperture radar (SAR) images is heavily impaired by speckle noise, hence despeckling is a crucial preliminary step in scene analysis algorithms. The recent success of deep learning envisions a new…

Image and Video Processing · Electrical Eng. & Systems 2020-07-07 Andrea Bordone Molini , Diego Valsesia , Giulia Fracastoro , Enrico Magli

Photon counting is a mode of processing astronomical observations of low-signal targets that have been observed using an electron-multiplying charge-coupled device (EMCCD). In photon counting, the EMCCD amplifies the signal, and a…

Instrumentation and Methods for Astrophysics · Physics 2024-01-02 Kevin Ludwick

Optical stellar interferometers have demonstrated milli-arcsecond resolution with few apertures spaced hundreds of meters apart. To obtain rich direct images, many apertures will be needed, for a better sampling of the incoming wavefront.…

Instrumentation and Methods for Astrophysics · Physics 2014-09-17 Arun Surya , Swapan K. Saha , Antoine Labeyrie

Due to the low flux of exoEarths, long exposure times are required to spectrally characterize them. During these long exposures, the contrast in the dark hole will degrade as the the optical system drifts from its initial DH state. To…

Instrumentation and Methods for Astrophysics · Physics 2023-10-02 Phillip K. Poon , Axel Potier , Garreth Ruane , Alex B. Walter , A J Eldorado Riggs , Matthew Noyes , Camilo Mejia Prada , Kyohoon Ahn , Olivier Guyon

In long adaptive optics corrected exposures, exoplanet detections are currently limited by speckle noise originating from the telescope and instrument optics, and it is expected that such noise will also limit future high-contrast imaging…

Astrophysics · Physics 2009-11-13 C. Marois , D. Lafreniere , B. Macintosh , R. Doyon

Technological advances in instrumentation have led to an exponential increase in exoplanet detection and scrutiny of stellar features such as spots and faculae. While the spots and faculae enable us to understand the stellar dynamics,…

Earth and Planetary Astrophysics · Physics 2022-02-04 Sahil Agarwal , John S. Wettlaufer

A Superoscillatory lens (SOL) is known to produce a sub-diffraction hotspot which is useful for high-resolution imaging. However, high-energy rings called sidelobes coexist with the central hotspot. Additionally, SOLs have not yet been…

Direct imaging of extrasolar planets with future space-based coronagraphic telescopes may provide a means of detecting companion moons at wavelengths where the moon outshines the planet. We propose a detection strategy based on the…

Earth and Planetary Astrophysics · Physics 2015-10-14 Eric Agol , Tiffany Jansen , Brianna Lacy , Tyler Robinson , Victoria Meadows

Hyperspectral pansharpening has received much attention in recent years due to technological and methodological advances that open the door to new application scenarios. However, research on this topic is only now gaining momentum. The most…

Computer Vision and Pattern Recognition · Computer Science 2025-07-16 Giuseppe Guarino , Matteo Ciotola , Gemine Vivone , Giovanni Poggi , Giuseppe Scarpa

The Planetary Nebula Spectrograph is a dedicated instrument for measuring radial velocity of individual Planetary Nebulae (PNe) in galaxies. This new instrument is providing crucial data with which to probe the structure of dark halos in…

Holographic displays promise several benefits including high quality 3D imagery, accurate accommodation cues, and compact form-factors. However, holography relies on coherent illumination which can create undesirable speckle noise in the…

Graphics · Computer Science 2023-09-20 Grace Kuo , Florian Schiffers , Douglas Lanman , Oliver Cossairt , Nathan Matsuda

Directly imaging Earth-like exoplanets (``exoEarths'') with a coronagraph instrument on a space telescope requires a stable wavefront with optical path differences limited to tens of picometers RMS during exposure times of a few hours.…

A noise-based non-parametric technique for detecting nebulous objects, for example, irregular or clumpy galaxies, and their structure in noise is introduced. "Noise-based" and "non-parametric" imply that this technique imposes negligible…

Instrumentation and Methods for Astrophysics · Physics 2015-09-08 Mohammad Akhlaghi , Takashi Ichikawa