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Related papers: Dissecting Galaxies with Adaptive Optics

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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…

Deconvolution is essential for radio interferometric imaging to produce scientific quality data because of finite sampling in the Fourier plane. Most deconvolution algorithms are based on CLEAN which uses a grid of image pixels, or clean…

Instrumentation and Methods for Astrophysics · Physics 2016-11-18 Sarod Yatawatta

The deflection of light in the strong field limit is an important test for alternative theories of gravity. However, solutions for the metric that allow for analytic computations are not always available. We implement a hybrid…

General Relativity and Quantum Cosmology · Physics 2021-06-09 Javier Chagoya , C. Ortiz , Benito Rodríguez , Armando A. Roque

Accurate astrometry and photometry of saturated and coronagraphic point spread functions (PSFs) are fundamental to both ground- and space-based high contrast imaging projects. For ground-based adaptive optics imaging, differential…

Astrophysics · Physics 2008-11-26 C. Marois , D. Lafreniere , B. Macintosh , R. Doyon

We explore the impact of different telescope apertures on the image simulation and deconvolution processes within the context of a synthetic star field. Using HCIPy and Python programming, we modelled six telescope apertures namely…

Instrumentation and Methods for Astrophysics · Physics 2024-02-09 Jyotika Roychowdhury , Kevin Derby , Daewook Kim

We summarize some of the compelling new scientific opportunities for understanding stars and stellar systems that can be enabled by sub-milliarcsec (sub-mas) angular resolution, UV-Optical spectral imaging observations, which can reveal the…

It is widely believed that adaptive optics only has a role in correcting turbulent wavefronts on large telescopes using very bright reference stars. Unfortunately these are very scarce and many astronomical targets require wavefront…

Instrumentation and Methods for Astrophysics · Physics 2019-11-19 Craig Mackay

Exponential, de Vaucouleurs, and S\'ersic profiles are simple and successful models for fitting two-dimensional images of galaxies. One numerical issue encountered in this kind of fitting is the pixel rendering and convolution (or…

Instrumentation and Methods for Astrophysics · Physics 2015-06-11 David W. Hogg , Dustin Lang

We describe a first attempt to apply adaptive optics to the study of resolved stellar populations in galaxies. Advantages over traditional approaches are (i) improved spatial resolution and point-source sensitivity through adaptive optics,…

Astrophysics · Physics 2007-05-23 T. R. Bedding , D. Minniti , F. Courbin , B. Sams

Speckle photography can be used to monitor deformations of solid surfaces. The measuring characteristics, such as range or lateral resolution depend heavily on the optical recording and illumination set-up. This paper shows how, by the…

Optics · Physics 2014-01-30 Jose M. Diazdelacruz

Projected in the sky, galaxies are spatially-resolved objects. To understand how they formed and evolve it is necessary to study the spatial distribution of their observables. In this review talk, we briefly describe some scaling relations…

Astrophysics of Galaxies · Physics 2019-12-18 Jorge K. Barrera-Ballesteros

The study of the morphology of galaxies is important in order to understand the formation and evolution of galaxies and their sub-components as a function of luminosity, environment, and star-formation and galaxy assembly over cosmic time.…

Cosmology and Nongalactic Astrophysics · Physics 2012-01-12 Yogesh Wadadekar

High-fidelity spectroscopy presents challenges for both observations and in designing instruments. High-resolution and high-accuracy spectra are required for verifying hydrodynamic stellar atmospheres and for resolving intergalactic…

Instrumentation and Methods for Astrophysics · Physics 2015-05-18 Dainis Dravins

Deep imaging of the diffuse light emitted by the stellar fine structures and outer halos around galaxies is now often used to probe their past mass assembly. Because the extended halos survive longer than the relatively fragile tidal…

Astrophysics of Galaxies · Physics 2017-05-10 Emin Karabal , Pierre-Alain Duc , Harald Kuntschner , Pierre Chanial , Jean-Charles Cuillandre , Stephen Gwyn

Radio interferometry enables high-resolution imaging of astronomical radio sources by synthesizing a large effective aperture from an array of antennas and solving a deconvolution problem to reconstruct the image. Deep learning has emerged…

Instrumentation and Methods for Astrophysics · Physics 2026-03-11 Zihui Wu , Liam Connor , Samuel McCarty , Katherine L. Bouman

This paper is based on the opening lecture given at the 2017 edition of the Evry Schatzman school on high-angular resolution imaging of stars and their direct environment. Two relevant observing techniques: long baseline interferometry and…

Instrumentation and Methods for Astrophysics · Physics 2019-04-04 Frantz Martinache

High quality imaging usually requires bulky and expensive lenses to compensate geometric and chromatic aberrations. This poses high constraints on the optical hash or low cost applications. Although one can utilize algorithmic…

Image and Video Processing · Electrical Eng. & Systems 2021-08-20 Xiu Li , Jinli Suo , Weihang Zhang , Xin Yuan , Qionghai Dai

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

Lens time delays are a powerful probe of cosmology, provided that the gravitational potential of the main deflector can be modeled with sufficient precision. Recent work has shown that this can be achieved by detailed modeling of the host…

Cosmology and Nongalactic Astrophysics · Physics 2015-10-07 Xiao-Lei Meng , Tommaso Treu , Adriano Agnello , Matthew W. Auger , Kai Liao , Philip J. Marshall

The CFHT Adaptive Optics Bonnette (AOB) has been used to obtain high spatial resolution (0.1") observations of several extragalactic targets including the nuclei of nearby galaxies, high redshift galaxies, AGN, radiogalaxies, the host…

Astrophysics · Physics 2007-05-23 David Crampton