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Related papers: Fully achromatic nulling interferometer (FANI) for…

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In this communication are presented some complements to a recent paper entitled "Simple Fourier optics formalism for high angular resolution systems and nulling interferometry", dealing with imaging and nulling capacities of a few types of…

Optics · Physics 2015-05-18 François Hénault

To date, the search for radio technosignatures has focused on sky location as a primary discriminant between technosignature candidates and anthropogenic radio frequency interference (RFI). In this work, we investigate the possibility of…

Instrumentation and Methods for Astrophysics · Physics 2023-07-19 Bryan Brzycki , Andrew P. V. Siemion , Imke de Pater , James M. Cordes , Vishal Gajjar , Brian Lacki , Sofia Sheikh

The NIR is less influenced by dust extinction than optical light. This enables us to look to an extent through dusty regions. In addition, it is sensitive to the mass-dominating stellar population. The combination of NIR imaging and…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-23 Semir Smajić , Sebastian Fischer , Jenz Zuther , Monica Valencia-S. , Andreas Eckart

We report low resolution near infrared spectroscopic observations of the eruptive star FU Orionis using the Integral Field Spectrograph Project 1640 installed at the Palomar Hale telescope. This work focuses on elucidating the nature of the…

Purpose: Low-field MRI systems operate at single MHz-range frequencies, where signal losses are primarily dominated by thermal noise from the radio-frequency (RF) receive coils. Achieving operation close to this limit is essential for…

Medical Physics · Physics 2026-03-09 Teresa Guallart-Naval , José M. Algarín , Joseba Alonso

Full Waveform Inversion (FWI) is a successful and well-established inverse method for reconstructing material models from measured wave signals. In the field of seismic exploration, FWI has proven particularly successful in the…

Computational Engineering, Finance, and Science · Computer Science 2023-12-05 Tim Bürchner , Philipp Kopp , Stefan Kollmannsberger , Ernst Rank

The combination of the AKARI and WISE infrared all-sky surveys provides an unique opportunity to identify and characterize the most highly dust obscured AGNs in the universe. Dust-obscured AGNs are not easily detectable and potentially…

Astrophysics of Galaxies · Physics 2018-08-06 Anson Lam , Matthew A. Malkan , Edward L. Wright

We present a novel method for direct detection and characterization of exoplanets from space. This method uses four collecting telescopes, combined with phase chopping and a spectrometer, with observations on only a few baselines rather…

Earth and Planetary Astrophysics · Physics 2015-05-27 Taro Matsuo , Wesley A. Traub , Makoto Hattori , Motohide Tamura

In the cm-wavelength range, an extraterrestrial electromagnetic narrow band (sine wave) beacon is an excellent choice to get alien attention across interstellar distances because 1) it is not strongly affected by interstellar /…

Instrumentation and Methods for Astrophysics · Physics 2018-05-08 G. R. Harp , R. F. Ackermann , Samantha K. Blair , J. Arbunich , P. R. Backus , J. C. Tarter , the ATA Team

In this communication are presented rigorous and approximate analytical expressions of the Point Spread Function (PSF) and Field of View (FoV) achievable by multi-aperture Fizeau interferometers, either of the imaging or nulling types. The…

Instrumentation and Methods for Astrophysics · Physics 2015-06-22 F. Henault

Revealing what fraction of galaxies harbor AGN is central in understanding black hole accretion history of the Universe. However, optical and soft X-ray surveys miss the most highly obscured AGNs. Infrared (IR), instead, is more robust…

Astrophysics of Galaxies · Physics 2019-03-20 Chia-Ying Chiang , Tomotsugu Goto , Tetsuya Hashimoto , Seong-Jin Kim , Hideo Matsuhara , Nagisa Oi

Double-Fourier interferometry is the most viable path to sub-arcsecond spatial resolution for future astronomical instruments that will observe the universe at far-infrared wavelengths. The double transform spatio-spectral interferometry…

The Very Long Baseline Interferometry (VLBI) monitoring program TANAMI provides bi-monthly, dualfrequency (8GHz and 22GHz) observations of extragalactic jets with milliarcsecond resolution south of -30 deg declination using the Australian…

High Energy Astrophysical Phenomena · Physics 2012-05-08 Cornelia Müller , M. Böck , J. Wilms , M. Kadler , R. Ojha , J. Blanchard , M. Dutka , E. Ros

The direct detection and imaging of exoplanets requires the use of high-contrast adaptive optics (AO). In these systems quasi-static aberrations need to be highly corrected and calibrated. In order to achieve this, the pupil-modulated…

Instrumentation and Methods for Astrophysics · Physics 2022-05-25 Nicolas Dubost , Nazim Ali Bharmal , Marc Dubbeldam , Richard M. Myers

The Planet Formation Imager (PFI) initiative aims at developing the next generation large scale facility for imaging astronomical optical interferometry operating in the mid-infrared. Here we report on the progress of the Planet Formation…

Instrumentation and Methods for Astrophysics · Physics 2016-08-18 Stefano Minardi , Sylvestre Lacour , Jean-Philippe Berger , Lucas Labadie , Robert R. Thomson , Chris Haniff , Michael Ireland

Exoplanets with a long orbital period are difficult to discover by extant methods. Our first publication (Lerner, P., A. Mayer, T. E. Sullivan. 2023. A new method for the discovery of the distant exoplanets. SPIE Proceedings 12680:…

Instrumentation and Detectors · Physics 2025-07-16 Peter B. Lerner

Measurement of interferometric parameters values is affected by phase disturbance due especially to atmospheric turbulences. Algorithms of fringe sensing, aimed at fringe parameters identification, are based on interferometric models that…

Instrumentation and Methods for Astrophysics · Physics 2009-08-27 Bonino Donata

Direct imaging characterization of extrasolar planets is often done at low spectral resolution. We model the spectrograph for the Gemini Planet Imager upgrade (GPI 2.0) and assess the instrument's potential for allowing observers to…

Earth and Planetary Astrophysics · Physics 2022-08-31 Arlene Aleman , Bruce Macintosh , Mary Anne Limbach , Mark Marley , Jeffrey Chilcote , Quinn Konopacky , Dmitry Savransky

The dispersed fixed-delay interferometer (DFDI) represents a new instrument concept for high-precision radial velocity (RV) surveys for extrasolar planets. A combination of Michelson interferometer and medium-resolution spectrograph, it has…

Instrumentation and Methods for Astrophysics · Physics 2010-07-02 Julian C. van Eyken , Jian Ge , Suvrath Mahadevan