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Related papers: Segmented coronagraph design and analysis (SCDA): …

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For future space infrared astronomical coronagraphy, we perform experimental studies on the application of aluminum mirrors to a coronagraph. Cooled reflective optics is required for broad-band mid-infrared observations in space, while…

Instrumentation and Methods for Astrophysics · Physics 2016-03-09 Shinji Oseki , Shinki Oyabu , Daisuke Ishihara , Keigo Enya , Kanae Haze , Takayuki Kotani , Hidehiro Kaneda , Miho Nishiyama , Lyu Abe , Tomoyasu Yamamuro

Vessel stenosis is a major risk factor in cardiovascular diseases (CVD). To analyze the degree of vessel stenosis for supporting the treatment management, extraction of coronary artery area from Computed Tomographic Angiography (CTA) is…

Image and Video Processing · Electrical Eng. & Systems 2019-07-30 Yo-Chuan Chen , Yi-Chen Lin , Ching-Ping Wang , Chia-Yen Lee , Wen-Jeng Lee , Tzung-Dau Wang , Chung-Ming Chen

Extreme wavefront correction is required for coronagraphs on future space telescopes to reach 1e-8 or better starlight suppression for the direct imaging and characterization of exoplanets in reflected light. Thus, a suite of wavefront…

Morphological analysis and identification of pathologies in the aorta are important for cardiovascular diagnosis and risk assessment in patients. Manual annotation is time-consuming and cumbersome in CT scans acquired without contrast…

Computer Vision and Pattern Recognition · Computer Science 2018-10-16 Julia M. H. Noothout , Bob D. de Vos , Jelmer M. Wolterink , Ivana Isgum

The direct detection and characterization of exoplanets will be a major scientific driver over the next decade, involving the development of very large telescopes and requires high-contrast imaging close to the optical axis. Some complex…

Instrumentation and Methods for Astrophysics · Physics 2017-05-16 M. Beaulieu , L. Abe , P. Martinez , P. Baudoz , C. Gouvret , F. Vakili

The programmable Liquid-crystal Active Coronagraphic Imager for the DAG Telescope (PLACID) instrument will be installed on the Turkish 4-m Telescope by the fall of 2024 and is expected to be on-sky by the end of the year. PLACID will be the…

Instrumentation and Methods for Astrophysics · Physics 2024-08-21 Liurong Lin , Axel Potier , Ruben Tandon , Jonas G. Kühn

Energetic X-ray radiations emitted from various accretion systems are widely considered to be produced by Comptonization in the hot corona. The corona and its interaction with the disc play an essential role in the evolution of the system…

High Energy Astrophysical Phenomena · Physics 2022-06-10 Xiao-lin Yang , Jian-cheng Wang , Chu-yuan Yang

We present the results of the first laboratory experiment of checkerboard shaped pupil binary mask coronagraphs using visible light, in the context of the R&D activities for future mid-infrared space missions such as the 3.5 m SPICA…

Astrophysics · Physics 2009-11-11 K. Enya , S. Tanaka , L. Abe , T. Nakagawa

Accurate segmentation of coronary arteries is a pivotal process in assessing cardiovascular diseases. However, the intricate structure of the cardiovascular system presents significant challenges for automatic segmentation, especially when…

Image and Video Processing · Electrical Eng. & Systems 2023-11-20 Jonghoe Ku , Yong-Hee Lee , Junsup Shin , In Kyu Lee , Hyun-Woo Kim

Oncoming exoplanet spectro-imagers like the Planetary Camera and Spectrograph (PCS) for the Extremely Large Telescope (ELT) will aim for a new class of exoplanets, including Earth-like planets evolving around M dwarfs i.e., closer than…

Instrumentation and Methods for Astrophysics · Physics 2022-09-14 Lucie Leboulleux , Alexis Carlotti , Stéphane Curaba , Alain Delboulbé , Laurent Jocou , Thibaut Moulin , Laurence Gluck , Marie-Hélène Sztefek

We present a MIR coronagraph to target the direct observation of extrasolar planets for SPICA, in which a coronagraph is currently regarded as an option of the focal plane instruments. The primary target of the SPICA coronagraph is the…

Earth and Planetary Astrophysics · Physics 2019-08-14 Keigo Enya

Circumstellar environments are now routinely observed by dedicated high-contrast imagers on large, ground-based observatories. These facilities combine extreme adaptive optics and coronagraphy to achieve unprecedented sensitivities for…

Instrumentation and Methods for Astrophysics · Physics 2018-06-28 A. Vigan , M. N'Diaye , K. Dohlen , J. Milli , Z. Wahhaj , J. -F. Sauvage , J. -L. Beuzit , R. Pourcelot , D. Mouillet , G. Zins

Earlier apodized-pupil Lyot coronagraphs (APLC) have been studied and developed to enable high-contrast imaging for exoplanet detection and characterization with present-day ground-based telescopes. With the current interest in the…

Instrumentation and Methods for Astrophysics · Physics 2015-05-19 Patrice Martinez

Phase masks coronagraphs can be seen as linear systems that spatially redistribute, in the pupil plane, the energy collected by the telescope. Most of the on-axis light must ideally be rejected outside the aperture to be blocked with a Lyot…

Instrumentation and Methods for Astrophysics · Physics 2015-06-12 Alexis Carlotti

Despite the success of advanced segmentation frameworks such as TotalSegmentator (TS), accurate segmentations of the left atrial appendage (LAA), coronary arteries (CAs), and pulmonary veins (PVs) remain a significant challenge in medical…

Computer Vision and Pattern Recognition · Computer Science 2025-10-08 Bjoern Hansen , Jonas Pedersen , Klaus F. Kofoed , Oscar Camara , Rasmus R. Paulsen , Kristine Soerensen

We describe a coronagraphic optic for use with CONICA at the VLT that provides suppression of diffraction from 1.8 to 7 lambda/D at 4.05 microns, an optimal wavelength for direct imaging of cool extrasolar planets. The optic is designed to…

Instrumentation and Methods for Astrophysics · Physics 2015-05-19 Matthew A. Kenworthy , Sascha P. Quanz , Michael R. Meyer , Markus E. Kasper , Rainer Lenzen , Johanan L. Codona , Julien H. V. Girard , Philip M. Hinz

Coronagraphy is a powerful technique to achieve high contrast imaging and hence to image faint companions around bright targets. Various concepts have been used in the visible and near-infrared regimes, while coronagraphic applications in…

Space-based stellar coronagraph instruments aim to directly image exoplanets that are a fraction of an arcsecond separation and ten billion times fainter than their host star. To achieve this, one or more deformable mirrors (DMs) are used…

The optical vortex coronagraph is potentially a remarkably effective device, at least for an ideal unobstructed telescope. Most ground-based telescopes however suffer from central obscuration and also have to operate through the aberrations…

Astrophysics · Physics 2009-11-13 Charles Jenkins

Small-angle coronagraphy is technically and scientifically appealing because it enables the use of smaller telescopes, allows covering wider wavelength ranges, and potentially increases the yield and completeness of circumstellar…