English
Related papers

Related papers: High spatial resolution and high contrast optical …

200 papers

Recently introduced angular-memory-effect based techniques enable non-invasive imaging of objects hidden behind thin scattering layers. However, both the speckle-correlation and the bispectrum analysis are based on the statistical average…

Optics · Physics 2017-11-22 Tengfei Wu , Jonathan Dong , Xiaopeng Shao , Sylvain Gigan

A new method for dark field imaging is introduced which uses scanned electron diffraction (or 4DSTEM - 4-dimensional scanning transmission electron microscopy) datasets as its input. Instead of working on simple summation of intensity, it…

Materials Science · Physics 2024-09-18 Ian MacLaren , Andrew T. Fraser , Matthew R. Lipsett , Colin Ophus

We characterize the sensitivity of a double point-spread function (PSF) fitting algorithm -- employing empirical, position-dependent PSF models -- for detecting companions using the infrared channel of the Wide Field Camera 3 (WFC3/IR) on…

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…

We report results of a re-analysis of archival Spitzer IRAC direct imaging surveys encompassing a variety of nearby stars. Our sample is generated from the combined observations of 73 young stars (median age, distance, spectral type = 85…

Earth and Planetary Astrophysics · Physics 2016-06-22 Stephen Durkan , Markus Janson , Joseph Carson

In the two decades since the first extra-solar planet was discovered, the detection and characterization of extra-solar planets has become one of the key endeavors in all of modern science. Recently direct detection techniques such as…

We present preliminary results from the first part of the LuckyCam late M-dwarf binarity survey. We survey a sample of 48 nearby ($<$40 pc) and red (M5-M9) stars with the novel high angular resolution visible light imaging technique Lucky…

Astrophysics · Physics 2007-05-23 Nicholas M. Law , Simon T. Hodgkin , Craig D. Mackay , John E. Baldwin

Fourier imaging is an indirect imaging method which records the diffraction pattern of the object scene coherently in the focal plane of the imaging system and reconstructs the image using computational resources. The spatial resolution,…

Optics · Physics 2023-06-05 Hui Yuan , Alvydas Lisauskas , Mark D. Thomson , Hartmut G. Roskos

A long-held vision has been to realize diffraction-limited optical aperture synthesis over kilometer baselines. This will enable imaging of stellar surfaces and their environments, and reveal interacting gas flows in binary systems. An…

Instrumentation and Methods for Astrophysics · Physics 2015-08-12 Dainis Dravins , Tiphaine Lagadec , Paul D. Nuñez

The ongoing development of large infrared array detectors has enabled wide field, deep surveys to be undertaken. There are, however, a number of challenges in building an infrared instrument which has both excellent optical quality and high…

Astrophysics · Physics 2021-07-22 Coryn A. L. Bailer-Jones , Peter Bizenberger , Clemens Storz

We present the results of an adaptive optics survey for faint companions among Galactic O-type star systems (V < 8) using the Advanced Electro-Optical System (AEOS) 3.6-meter telescope on Haleakala. We surveyed these O star systems in…

The detection of high contrast companions at small angular separation appears feasible in conventional direct images using the self-calibration properties of interferometric observable quantities. In the high-Strehl regime, available from…

Instrumentation and Methods for Astrophysics · Physics 2015-05-30 Frantz Martinache

Structured illumination can reject out-of-focus signal from a sample, enabling high-speed and high-contrast imaging over large areas with widefield detection optics. Currently, this optical-sectioning technique is limited by image…

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

CONTEXT: Many massive stars have nearby companions whose presence hamper their characterization through spectroscopy. AIMS: We want to obtain spatially resolved spectroscopy of close massive visual binaries to derive their spectral types.…

Solar and Stellar Astrophysics · Physics 2018-08-01 J. Maíz Apellániz , R. H. Barbá , S. Simón-Díaz , A. Sota , E. Trigueros Páez , J. A. Caballero , E. J. Alfaro

We present observations with the planet finder SPHERE of a selected sample of the most promising radial velocity (RV) companions for high-contrast imaging. Using a Monte Carlo simulation to explore all the possible inclinations of the orbit…

We present the results of a speckle interferometric survey of Galactic massive stars that complements and expands upon a similar survey made over a decade ago. The speckle observations were made with the KPNO and CTIO 4 m telescopes and…

Starshades are a leading technology to enable the direct detection and spectroscopic characterization of Earth-like exoplanets. In an effort to advance starshade technology through system level demonstrations, the McMath-Pierce Solar…

Instrumentation and Methods for Astrophysics · Physics 2021-06-10 Anthony Harness , Webster Cash , Steve Warwick

We report on a new x-ray imaging method, which combines the high spatial resolution of coherent diffraction imaging with the ability of dark field microscopy to map grains within thick polycrystalline specimens. An x-ray objective serves to…

Instrumentation and Detectors · Physics 2020-07-15 Anders Filsøe Pedersen , Virginie Chamard , Carsten Detlefs , Tao Zhou , Dina Carbone , Henning Friis Poulsen

Nonlinear optical microscopy allows rapid high-resolution microscopy with image contrast generated from intrinsic properties of the sample. Established modalities such as multiphoton excited fluorescence and second/third-harmonic generation…

‹ Prev 1 4 5 6 7 8 10 Next ›