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Extra-solar planets have not been imaged directly with existing ground or space telescopes because they are too faint to be seen against the halo of the nearby bright star. Most techniques being explored to suppress the halo are achromatic,…

Astrophysics · Physics 2009-11-10 Johanan L. Codona , Roger Angel

Astrophysical polarization measurements provide some of the strongest constraints on the photon sector of the non-minimal Standard-Model Extension. This paper reviews some recent results obtained by combining optical linear and circular…

High Energy Physics - Phenomenology · Physics 2022-07-12 Fabian Kislat

This paper presents initial results from the ESA-funded ``SUPPPPRESS'' project, which aims to develop high-performance liquid-crystal coronagraphs for direct imaging of Earth-like exoplanets in reflected light. The project focuses on…

We study a strategy to determine miscalibrated polarization angles of cosmic microwave background (CMB) experiments using the observed $EB$ polarization power spectra of CMB and Galactic foreground emission. We apply the methodology of…

Cosmology and Nongalactic Astrophysics · Physics 2020-06-30 Yuto Minami

The Internal Linear Combination (ILC) is widely used to extract the cosmic microwave background (CMB) signal from multi-frequency observation maps, especially for Satellite experiments with quasi-full sky coverage. We extend ILC method to…

Cosmology and Nongalactic Astrophysics · Physics 2022-07-29 Zirui Zhang , Yang Liu , Si-Yu Li , De-Liang Wu , Haifeng Li , Hong Li

The polarization of the cosmic microwave background (CMB) can be used to search for parity-violating processes like that predicted by a Chern-Simons coupling to a light pseudoscalar field. Such an interaction rotates $E$ modes into $B$…

A discrete tomography method has been developed that is able to reconstruct three-dimensional coronal mass ejection (CME) density structure. We test the method by producing synthetic coronagraph imagery for three events using the…

Understanding the 3D structure of coronal mass ejections (CMEs) is crucial for understanding the nature and origin of solar eruptions. To derive information on the 3D structure of CMEs from white-light (total and polarized brightness)…

Solar and Stellar Astrophysics · Physics 2015-10-14 Paolo Pagano , Alessandro Bemporad , Duncan Mackay

Context. In the context of direct imaging of exoplanets, coronagraphs are commonly proposed to reach the required very high contrast levels. However, wavefront aberrations induce speckles in their focal plane and limit their performance.…

Instrumentation and Methods for Astrophysics · Physics 2015-06-18 Johan Mazoyer , Pierre Baudoz , Raphaël Galicher , Gérard Rousset

Stellar coronagraphs rely on deformable mirrors (DMs) to correct wavefront errors and create high contrast images. Imperfect control of the DM limits the achievable contrast and, therefore, the DM control electronics must provide fine…

High-dispersion coronagraphy (HDC) optimally combines high contrast imaging techniques such as adaptive optics/wavefront control plus coronagraphy to high spectral resolution spectroscopy. HDC is a critical pathway towards fully…

We propose a method for sensitive parallel detection of low-frequency electromagnetic fields based on the fine structure interactions in paramagnetic polar molecules. Compared to the recently implemented scheme employing ultracold $^{87}$Rb…

Atomic Physics · Physics 2013-04-25 Sergey V. Alyabyshev , Mikhail Lemeshko , Roman V. Krems

The Roman Space Telescope will be a critical mission to demonstrate high-contrast imaging technologies allowing for the characterisation of exoplanets in reflected light. It will demonstrate $10^{-7}$ contrast limits or better at 3--9…

Instrumentation and Methods for Astrophysics · Physics 2024-09-18 Alexis Lau , Élodie Choquet , Lisa Altinier , Iva Laginja , Rémi Soummer , Laurent Pueyo , Nicolas Godoy , Arthur Vigan , David Mary

Direct imaging of exoplanets by reflected starlight is extremely challenging due to the large luminosity ratio to the primary star. Wave-front control is a critical technique to attenuate the speckle noise in order to achieve an extremely…

Instrumentation and Methods for Astrophysics · Physics 2016-11-22 Jiangpei Dou , Deqing Ren

Context: The detection and characterization of Earth-like exoplanets (exoEarths) from space requires exquisite wavefront stability at contrast levels of $10^{-10}$. On segmented telescopes in particular, aberrations induced by cophasing…

Coronagraphs allow for faint off-axis exoplanets to be observed, but are limited to angular separations greater than a few beam widths. Accessing closer-in separations would greatly increase the expected number of detectable planets, which…

Polarization aberrations originating from the telescope and high-contrast imaging instrument optics introduce polarization-dependent speckles and associated errors in the image plane, affecting the measured exoplanet signal. Understanding…

Instrumentation and Methods for Astrophysics · Physics 2024-06-28 Ramya M Anche , Kyle J. Van Gorkom , Jaren N. Ashcraft , Ewan Douglas , Emory L Jenkins , Sebastiaan Y. Haffert , Maxwell A. Millar-Blanchaer

The design of liquid-crystal diffractive phase plate coronagraphs for ground-based and space-based high-contrast imaging systems is limited by the trade-off between spectral bandwidth and polarization leakage. We demonstrate that by…

Instrumentation and Methods for Astrophysics · Physics 2020-03-13 David S. Doelman , Emiel H. Por , Garreth Ruane , Michael J. Escuti , Frans Snik

Polarized light microscopy, as a contrast-enhancing technique for optically anisotropic materials, is a method well suited for the investigation of a wide variety of effects in solid-state physics, as for example birefringence in crystals…

Instrumentation and Detectors · Physics 2017-12-19 Matthias Lange , Stefan Guénon , Felix Lever , Reinhold Kleiner , Dieter Koelle

Cool Planet Imaging Coronagraph (CPI-C) on Chinese Space Station Survey Telescope (CSST) is proposed to direct image the cool planets around nearby solar-type stars (within 40 pc). The core scientific objective of CPI-C is to conduct…

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