English
Related papers

Related papers: On-sky speckle nulling demonstration at small angu…

200 papers

The paper introduces the software Spectangular for spectral disentangling via singular value decomposition with global optimisation of the orbital parameters of the stellar system or radial velocities of the individual observations. We will…

Instrumentation and Methods for Astrophysics · Physics 2017-01-18 Daniel P. Sablowski , Michael Weber

Adaptive optics is a technique mostly used on large telescopes. It turns out to be challenging for smaller telescopes (0.5~2m) due to the small isoplanatic angle, small subapertures and high correction speeds needed at visible wavelengths,…

Instrumentation and Methods for Astrophysics · Physics 2023-10-12 Olivier Lai , Mark Chun , Stefan Kuiper , Niek Doelman , Marcel Carbillet , Mamadou N'Diaye , Frantz Martinache , Lyu Abe , Jean-Pierre Rivet , Dirk Schmidt

Adaptive optics (AO) have been used to correct wavefronts to achieve diffraction limited point spread functions in a broad range of optical applications, prominently ground-based astronomical telescopes operating in near infra-red. While…

Instrumentation and Methods for Astrophysics · Physics 2018-10-03 Alexandre J. T. S. Mello , Antonin H. Bouchez , Andrew Szentgyorgyi , Marcos A. van Dam , Henrique Lupinari

We present current status of H$\alpha$ high-contrast imaging observations with Subaru/SCExAO+VAMPIRES. Our adaptive optics correction at optical wavelengths in combination with (double) spectral differential imaging (SDI) and angular…

Instrumentation and Methods for Astrophysics · Physics 2020-10-20 Taichi Uyama , Barnaby Norris , Nemanja Jovanovic , Julien Lozi , Peter Tuthill , Olivier Guyon , Tomoyuki Kudo , Jun Hashimoto , Motohide Tamura , Frantz Martinache

A key challenge of high contrast imaging (HCI) is to differentiate a speckle from an exoplanet signal. The sources of speckles are a combination of atmospheric residuals and aberrations in the non-common path. Those non-common path…

A high contrast coronagraph is expected to provide one of the promising ways to directly observe extra-solar planets. We present the newest results of our laboratory experiment investigating "rigid" coronagraph with a binary shaped…

Instrumentation and Methods for Astrophysics · Physics 2011-08-17 K. Enya , L. Abe , S. Tanaka , T. Nakagawa , K. Haze , T. Sato , T. Wakayama

The search for exoplanets is pushing adaptive optics systems on ground-based telescopes to their limits. Currently, we are limited by two sources of noise: the temporal control error and non-common path aberrations. First, the temporal…

Spectral characterization of young, giant exoplanets detected by direct imaging is one of the tasks of the new generation of high-contrast imagers. For this purpose, the VLT/SPHERE instrument includes a unique long-slit spectroscopy (LSS)…

The petaling effect, induced by pupil fragmentation from the telescope spider, drastically affects the performance of high contrast instruments by inducing core splitting on the PSF. Differential piston/tip/tilt aberrations within each…

In high-contrast space-based coronagraphs, one of the main limiting factors for imaging the dimmest exoplanets is the time varying nature of the residual starlight (speckles). Modern methods try to differentiate between the intensities of…

Instrumentation and Methods for Astrophysics · Physics 2019-09-04 Leonid Pogorelyuk , N. Jeremy Kasdin , Clarence W. Rowley

Vibrations are a key source of image degradation in ground-based instrumentation, especially for high-contrast imaging instruments. Vibrations reduce the quality of the correction provided by the adaptive optics system, blurring the science…

Instrumentation and Methods for Astrophysics · Physics 2018-09-25 Julien Lozi , Olivier Guyon , Nemanja Jovanovic , Naruhisa Takato , Garima Singh , Barnaby Norris , Hirofumi Okita , Takamasa Bando , Frantz Martinache

SAXO+ is a planned enhancement of the existing SAXO, the VLT/ SPHERE adaptive optics system, deployed on ESO's Very Large Telescope. This upgrade is designed to significantly enhance the instrument's capacity to detect and analyze young…

High-contrast imaging data analysis depends on removing residual starlight from the host star to reveal planets and disks. Most observers do this with principal components analysis (i.e. KLIP) using modes computed from the science images…

Directly imaging exoplanets is challenging because quasi-static phase aberrations in the pupil plane (speckles) can mimic the signal of a companion at small angular separations. Kernel phase, which is a generalization of closure phase…

Earth and Planetary Astrophysics · Physics 2019-04-10 Jens Kammerer , Michael J. Ireland , Frantz Martinache , Julien H. Girard

Extreme adaptive optics systems are now in operation across the globe. These systems, capable of high order wavefront correction, deliver Strehl ratios of 90% in the near-infrared. Originally intended for the direct imaging of exoplanets,…

Instrumentation and Methods for Astrophysics · Physics 2016-11-09 Nemanja Jovanovic , Christian Schwab , Nick Cvetojevic , Olivier Guyon , Frantz Martinache

We present a status update for MagAO-X, a 2000 actuator, 3.6 kHz adaptive optics and coronagraph system for the Magellan Clay 6.5 m telescope. MagAO-X is optimized for high contrast imaging at visible wavelengths. Our primary science goals…

Light-based synthetic aperture (SA) imaging methods, such as Fourier Ptychography, have brought breakthrough high-resolution wide-field-of-view imaging capabilities to microscopy. While these technologies promise similar improvements in…

Optics · Physics 2025-09-29 Janith B. Senanayaka , Christopher A. Metzler

Direct imaging is the primary technique currently used to detect young and warm exoplanets and understand their formation scenarios. The extreme flux ratio between an exoplanet and its host star requires the use of coronagraphs to attenuate…

Instrumentation and Methods for Astrophysics · Physics 2023-06-01 Axel Potier , Zahed Wahhaj , Raphael Galicher , Johan Mazoyer , Pierre Baudoz , Gael Chauvin , Garreth Ruane

Chopping observations with a tip-tilt secondary mirror have conventionally been used in ground-based mid-infrared observations. However, it is not practical for next generation large telescopes to have a large tip-tilt mirror that moves at…

A prototype of a low cost Adaptive Optics (AO) system has been developed at the Instituto de Astrofisica de Andalucia (CSIC) and tested at the 2.2m telescope of the Calar Alto observatory. We present here the status of the project, which…

Instrumentation and Methods for Astrophysics · Physics 2015-05-19 J. Aceituno , S. F. Sanchez , J. L. Ortiz , F. J. Aceituno
‹ Prev 1 4 5 6 7 8 10 Next ›