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Habitable Worlds Observatory (HWO) presents a key challenge for technology development in the coming years, requiring a $>$ $100\times$ more stable system than \textit{JWST}. WaveDriver is a concept for a laser guide star spacecraft coupled…

Optical filters are used for a variety of purposes at astronomical telescopes. In the near infrared region, from 0.8 to 2.5 um, bandpass and edge filters are used to separate the different astronomical channels, such as the J, H, and K…

Instrumentation and Methods for Astrophysics · Physics 2015-05-30 S. Guenster , D. Ristau , R. Davies

The limits for adaptive-optics (AO) imaging at high contrast and high resolution are determined by residual phase errors from non-common-path aberrations not sensed by the wavefront sensor, especially for integral field spectrographs, where…

Instrumentation and Methods for Astrophysics · Physics 2015-06-22 Benjamin Pope , Niranjan Thatte , Rick Burruss , Matthias Tecza , Fraser Clarke , Garret Cotter

We present a study into the capabilities of integrated and spatially resolved integral field spectroscopy of galaxies at z=2-4 with the future HARMONI spectrograph for the European Extremely Large Telescope (E-ELT) using the simulation…

Astrophysics of Galaxies · Physics 2016-03-23 S. Kendrew , S. Zieleniewski , R. C. W. Houghton , N. Thatte , J. Devriendt , M. Tecza , F. Clarke , K. O'Brien , B. Häussler

We developed a Python based framework for astronomical image processing and analysis. Astronomical image loading, normalizing, stacking, and filtering processes represent visible range images from grayscale. Besides, the blending process…

Instrumentation and Methods for Astrophysics · Physics 2024-10-10 Tanmoy Bhowmik , MD Fardin Islam , Kazi Nusrat Tasneem , Rantideb Roy , Rownok Shahariar

The sky is a major component of the appearance of a photograph, and its color and tone can strongly influence the mood of a picture. In nighttime photography, the sky can also suffer from noise and color artifacts. For this reason, there is…

Computer Vision and Pattern Recognition · Computer Science 2020-06-19 Orly Liba , Longqi Cai , Yun-Ta Tsai , Elad Eban , Yair Movshovitz-Attias , Yael Pritch , Huizhong Chen , Jonathan T. Barron

Astronomers working with faint targets will benefit greatly from improved image quality on current and planned ground-based telescopes. At present, most adaptive optic systems are targeted at the highest resolution with bright guide stars.…

Instrumentation and Methods for Astrophysics · Physics 2020-01-30 Craig Mackay

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

One of the key-points for the future developments of the multiconjugate adaptive optics for the astronomy is the availability of the correction for a large fraction of the sky. The sky coverage represents one of the limits of the existing…

Instrumentation and Methods for Astrophysics · Physics 2014-11-20 Carmelo Arcidiacono , Emiliano Diolaiti , Roberto Ragazzoni , Jacopo Farinato , Elise Vernet

Extra-solar planets have not been imaged directly with existing ground or space telescopes because they are too faint to be seen against the halo of the nearby bright star. Most techniques being explored to suppress the halo are achromatic,…

Astrophysics · Physics 2009-11-10 Johanan L. Codona , Roger Angel

Laser guide stars (LGS) are used in many adaptive optics systems to extend sky coverage. The most common wavefront sensor used in combination with a LGS is a Shack-Hartmann wavefront sensor (SHWFS). The Shack-Hartmann has a major…

Instrumentation and Methods for Astrophysics · Physics 2020-12-07 Sebastiaan Y. Haffert , Christoph U. Keller , Richard Dekany

The cosmological global (sky-averaged) 21-cm signal is a powerful tool to probe the evolution of the intergalactic medium (IGM) in high-redshift Universe ($z \leq 6$). One of the biggest observational challenges is to remove the foreground…

Instrumentation and Methods for Astrophysics · Physics 2018-11-14 Bang D. Nhan , Richard F. Bradley , Jack O. Burns

We propose to explore a cascade extreme Adaptive optics (ExAO) approach with a second stage based on a Zernike wavefront sensor (ZWFS) for exoplanet imaging and spectroscopy. Most exoplanet imagers currently use a single-stage ExAO to…

Instrumentation and Methods for Astrophysics · Physics 2023-09-20 Mamadou N'Diaye , Arthur Vigan , Byron Engler , Markus Kasper , Serban Leveratto , Johan Floriot , Michel Marcos , Christophe Bailet , Kjetil Dohlen

The detection and characterisation of extra-solar planets is a major theme driving modern astronomy, with the vast majority of such measurements being achieved by Doppler radial-velocity and transit observations. Another technique -- direct…

Instrumentation and Methods for Astrophysics · Physics 2015-06-19 Barnaby Norris , Nick Cvetojevic , Simon Gross , Nemanja Jovanovic , Paul N. Stewart , Ned Charles , Jon S. Lawrence , Michael J. Withford , Peter Tuthill

The performance of laser-based active sensing has been severely limited by two types of noise: electrical noise, stemming from elements; optical noise, laser jamming from an eavesdropper and background from environment. Conventional methods…

Orbital angular momentum (OAM) detection underpins almost all aspects of vortex beams' advances such as communication and quantum analogy. Conventional schemes are frustrated by low speed, complicated system, limited detection range. Here,…

Emerging Technologies · Computer Science 2022-09-07 Hao Wang , Ziyu Zhan , Futai Hu , Yuan Meng , Zeqi Liu , Xing Fu , Qiang Liu

In 2006 ESO Council authorized a Phase B study of a European AO-telescope with a 42 m segmented primary with a 5-mirror design, the E-ELT. Several reports and working groups have already presented science cases for an E-ELT, specifically…

Astrophysics of Galaxies · Physics 2015-05-18 Nils Ryde

We investigate the limits of ground-based astrometry with adaptive optics using the core of the Galactic globular cluster M5. Adaptive optics systems provide near diffraction-limit imaging with the world's largest telescopes. The…

Astrophysics · Physics 2009-11-13 P. B. Cameron , M. C. Britton , S. R. Kulkarni

Substellar companions such as exoplanets and brown dwarfs exhibit changes in brightness arising from top-of-atmosphere inhomogeneities, providing insights into their atmospheric structure and dynamics. This variability can be measured in…

The IACOB and OWN surveys are two ambitious complementary observational projects which have made available a large multi-epoch spectroscopic database of optical high resolution spectra of Galactic massive O-type stars. As a first step in…

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