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Related papers: Correcting for the ionosphere in the uv-plane

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Low-frequency radio observatories are reaching unprecedented levels of sensitivity in an effort to detect the 21 cm signal from the Cosmic Dawn. High precision is needed because the expected signal is overwhelmed by foreground…

Instrumentation and Methods for Astrophysics · Physics 2022-03-14 Adam E. Lanman , Steven G. Murray , Daniel C. Jacobs

Inversion codes allow reconstructing a model atmosphere from observations. With the inclusion of optically thick lines that form in the solar chromosphere, such modelling is computationally very expensive because a non-LTE evaluation of the…

Solar and Stellar Astrophysics · Physics 2019-04-19 Alberto Sainz Dalda , Jaime de la Cruz Rodríguez , Bart De Pontieu , Milan Gošić

We describe a method of white-beam inelastic neutron scattering for improved measurement efficiency. The method consists of matrix inversion and selective extraction. The former is to resolve each incident energy component from the…

Materials Science · Physics 2015-03-19 K. Tomiyasu , M. Matsuura , H. Kimura , K. Iwasa , K. Ohoyama , T. Yokoo , S. Itoh , E. Kudoh , T. Sato , M. Fujita

We present an atmospheric model tailored for the interactive visualization of planetary surfaces. As the exploration of the solar system is progressing with increasingly accurate missions and instruments, the faithful visualization of…

Human-Computer Interaction · Computer Science 2020-10-08 Jonathas Costa , Alexander Bock , Carter Emmart , Charles Hansen , Anders Ynnerman , Claudio Silva

The space-time correlations of streams of photons can provide fundamentally new channels of information about the Universe. Today's astronomical observations essentially measure certain amplitude coherence functions produced by a source.…

Instrumentation and Methods for Astrophysics · Physics 2009-03-03 C. Barbieri , M. K. Daniel , W. J. de Wit , D. Dravins , H. Jensen , P. Kervella , S. Le Bohec , F. Malbet , P. Nunez , J. P. Ralston , E. N. Ribak

Context. Recently our ability to study stars using asteroseismic techniques has increased dramatically, largely through the use of space based photometric observations. Work has also been done using ground based spectroscopic observations…

Solar and Stellar Astrophysics · Physics 2018-10-03 Jesper Schou

We present a new measurement of the energy spectrum of iron nuclei in cosmic rays from 20 to 500 TeV. The measurement makes use of a template-based analysis method, which, for the first time, is applied to the energy reconstruction of…

We propose a new method to detect off-pulse (unpulsed and/or continuous) emission from pulsars, using the intensity modulations associated with interstellar scintillation. Our technique involves obtaining the dynamic spectra, separately for…

High Energy Astrophysical Phenomena · Physics 2018-05-23 Kumar Ravi , Avinash A. Deshpande

Unmanned aerial vehicles (UAVs) can offer timely and cost-effective delivery of high-quality sensing data. How- ever, deciding when and where to take measurements in complex environments remains an open challenge. To address this issue, we…

Robotics · Computer Science 2017-03-09 Marija Popovic , Teresa Vidal-Calleja , Gregory Hitz , Inkyu Sa , Roland Siegwart , Juan Nieto

Context. We are operating an elastic LIDAR for the monitoring of atmospheric conditions during regular observations of the MAGIC Telescopes. Aims. We present and evaluate methods to convert aerosol extinction profiles, obtained with the…

We calculate the fully differential medium-induced radiative spectrum at next-to-leading order (NLO) accuracy within the Improved Opacity Expansion (IOE) framework. This scheme allows us to gain analytical control of the radiative spectrum…

High Energy Physics - Phenomenology · Physics 2022-01-26 João Barata , Yacine Mehtar-Tani , Alba Soto-Ontoso , Konrad Tywoniuk

In order to understand the positional uncertainties of arbitrary objects in several of the current major databases containing astrometric information, a sample of extragalactic radio sources with precise positions in the International…

Astrophysics · Physics 2009-10-31 Eric W. Deutsch

Aims: In view of the substantial uncertainties regarding the possible dynamics of the dark energy, we aim at constraining the expansion rate of the universe without reference to a specific Friedmann model and its parameters. Methods: We…

Astrophysics · Physics 2008-04-08 Claudia Mignone , Matthias Bartelmann

Ultra-wideband (UWB) is the state-of-the-art and most popular technology for wireless localization. Nevertheless, precise ranging and localization in non-line-of-sight (NLoS) conditions is still an open research topic. Indeed, multipath…

Machine Learning · Computer Science 2021-05-06 Simone Angarano , Vittorio Mazzia , Francesco Salvetti , Giovanni Fantin , Marcello Chiaberge

Light injected into a spherical dielectric body may be confined very efficiently via the mechanism of total internal reflection. The frequencies that are most confined are called resonances. If the shape of the body deviates from the…

Optics · Physics 2020-09-30 Julius Gohsrich

Electron density irregularities in the ionosphere are known to be magnetically anisotropic, preferentially elongated along the lines of force. While many studies of their morphology have been undertaken by topside sounding and whistler…

We present a method to measure the spectral density of in-band optical transmission impairments without coherent electrical reception and digital signal processing at the receiver. We determine the method's accuracy by numerical simulations…

Signal Processing · Electrical Eng. & Systems 2021-07-12 Sylvain Almonacil , Matteo Lonardi , Philippe Jenneve , Nicolas Dubreuil

We consider scalar field theory with space and space-time-dependent non-commutativity. In perturbation theory, we find that the structure of the UV/IR mixing is quite different from cases with constant non-commutativity. In particular,…

High Energy Physics - Theory · Physics 2016-09-06 Daniel Robbins , Savdeep Sethi

Applying a transformation to a non-Gaussian field can enhance the information content of the resulting power spectrum, by reducing the correlations between Fourier modes. In the context of weak gravitational lensing, it has been shown that…

Cosmology and Nongalactic Astrophysics · Physics 2015-12-16 Fergus Simpson , Joachim Harnois-Déraps , Catherine Heymans , Raul Jimenez , Benjamin Joachimi , Licia Verde

Finding reliably and efficiently the spectrum of the resonant states of an optical system under varying parameters of the medium surrounding it is a technologically important task, primarily due to various sensing applications.…

Optics · Physics 2023-09-28 S. F. Almousa , E. A. Muljarov
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