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Related papers: Phase Closure Nulling: results from the 2009 campa…

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Zernike's phase contrast microscopy (PCM) is among the most widely used techniques for observing phase objects, but it lacks quantitative nature, as it cannot directly provide phase information. Current methods for computationally…

In this communication we present the first experimental results obtained on the Crossed-cubes nuller (CCN), that is a new type of Achromatic phase shifter (APS) based on a pair of crossed beamsplitter cubes. We review the general principle…

Instrumentation and Methods for Astrophysics · Physics 2016-12-14 Francois Henault , Brahim Arezki , Guillaume Bourdarot , Alain Spang

Object detection is a core problem in computer vision. With the development of deep ConvNets, the performance of object detectors has been dramatically improved. The deep ConvNets based object detectors mainly focus on regressing the…

Computer Vision and Pattern Recognition · Computer Science 2017-06-14 Xinggang Wang , Kaibing Chen , Zilong Huang , Cong Yao , Wenyu Liu

Observations of neutron stars may be used to study aspects of extremely dense matter, specifically a possibility of phase transitions to exotic states, such as de-confined quarks. We present a novel data analysis method for detecting…

High Energy Astrophysical Phenomena · Physics 2022-12-21 Filip Morawski , Michał Bejger

Context. Phase-mask coronagraphy is advantageous in terms of inner working angle and discovery space. It is however still plagued by drawbacks such as sensitivity to tip-tilt errors and chromatism. A nulling stellar coronagraph based on the…

Instrumentation and Methods for Astrophysics · Physics 2015-06-11 P. Bourget , N. Schuhler , D. Mawet , P. Haguenauer

We present a novel application of optical tunneling in the context of high-angular resolution, high-contrast techniques with the aim of improving direct imaging capabilities of faint companions in the vicinity of bright stars. In contrast…

Instrumentation and Methods for Astrophysics · Physics 2016-06-30 Dominik Derigs , Lucas Labadie , Dhriti Sundar Ghosh , Laëtitia Abel-Tibérini

Astrophysical observations of neutron stars probe the structure of dense nuclear matter and have the potential to reveal phase transitions at high densities. Most recent analyses are based on parametrized models of the equation of state…

High Energy Astrophysical Phenomena · Physics 2025-05-13 Reed Essick , Isaac Legred , Katerina Chatziioannou , Sophia Han , Philippe Landry

The Keck Planet Imager and Characterizer (KPIC) is an upgrade to the Keck II adaptive optics system that includes an active fiber injection unit (FIU) for efficiently routing light from exoplanets to NIRSPEC, a high-resolution spectrograph.…

Starlight suppression techniques for High-Contrast Imaging (HCI) are crucial to achieving the demanding contrast ratios and inner working angles required for detecting and characterizing exoplanets with a wide range of masses and…

Cosmic crystallography is based on the principle that peaks in the pair separation histogram (PSH) of objects in a catalogue should be induced by the high number of topologically lensed pairs that are separated by Clifford translations, in…

Astrophysics · Physics 2011-07-19 Andrzej Marecki , Boudewijn F. Roukema , Stanislaw Bajtlik

The Keck Planet Imager and Characterizer (KPIC) is an instrument at the Keck II telescope that enables high-resolution spectroscopy of directly imaged exoplanets and substellar companions. KPIC uses single-mode fibers to couple the adaptive…

This article describes the design features and the first test measurements obtained during the installation of a novel high resolution 2D neutron detection technique. The technique proposed in this work consists of a boron layer (enriched…

The motion or out-of-focus effect in digital images is the main reason for the blurred regions in defocused-blurred images. It may adversely affect various image features such as texture, pixel, and region. Therefore, it is important to…

Computer Vision and Pattern Recognition · Computer Science 2023-11-23 Sadia Basar , Mushtaq Ali , Abdul Waheed , Muneer Ahmad , Mahdi H. Miraz

We present a new pipeline developed to detect and characterize faint astronomical companions at small angular separation from the host star using sets of wide-field imaging observations not specifically designed for High Contrast Imaging…

Instrumentation and Methods for Astrophysics · Physics 2022-09-28 Giovanni M. Strampelli , Laurent Pueyo , Jonathan Aguilar , Antonio Aparicio , Gaspard Duchêne , Massimo Robberto

We discuss the theory of the Bracewell nulling interferometer and explicitly demonstrate that the phase of the "white light" null fringe is the same as the phase of the bright output from an ordinary stellar interferometer. As a consequence…

Astrophysics · Physics 2009-11-11 W. C. Danchi , J. Rajagopal , M. Kuchner , J. Richardson , D. Deming

Ptychography is an imaging technique which involves a sample being illuminated by a coherent, localized probe of illumination. When the probe interacts with the sample, the light is diffracted and a diffraction pattern is detected. Then the…

Numerical Analysis · Mathematics 2023-01-31 Mark Iwen , Michael Perlmutter , Mark Philip Roach

Context: Variations in the mass accretion rate appear to be responsible for the rapid transitions in spectral type that are observed in increasingly more active galactic nuclei (AGNs). These objects are now labeled "changing-look" AGNs and…

Astrophysics of Galaxies · Physics 2020-04-15 F. Marin , D. Hutsemékers

In this paper, we propose a novel unsupervised deep learning model, called PCA-based Convolutional Network (PCN). The architecture of PCN is composed of several feature extraction stages and a nonlinear output stage. Particularly, each…

Machine Learning · Computer Science 2015-05-15 Yanhai Gan , Jun Liu , Junyu Dong , Guoqiang Zhong

High-contrast imaging from space must overcome two major noise sources to successfully detect a terrestrial planet angularly close to its parent star: photon noise from diffracted star light, and speckle noise from star light scattered by…

Astrophysics · Physics 2009-11-13 Pascal J. Borde , Wesley A. Traub

The detection of galactic supernova (SN) neutrinos represents one of the future frontiers of low-energy neutrino physics and astrophysics. The neutron coherence of neutral currents (NC) allows quite large cross sections in the case of…

High Energy Physics - Phenomenology · Physics 2015-05-27 J. D. Vergados