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Related papers: Three dimensional Doppler tomography

200 papers

We formulate and investigate a statistical inverse problem of a random tomographic nature, where a probability density function on $\mathbb{R}^3$ is to be recovered from observation of finitely many of its two-dimensional projections in…

Statistics Theory · Mathematics 2009-09-03 Victor M. Panaretos

The Doppler technique measures the reflex radial motion of a star induced by the presence of companions and is the most successful method to detect exoplanets. If several planets are present, their signals will appear combined in the radial…

Astrophysics · Physics 2010-01-06 Guillem Anglada-Escude , Mercedes Lopez-Morales , John E. Chambers

This paper concerns electromagnetic 3D subsurface imaging in connection with sparsity of signal sources. We explored an imaging approach that can be implemented in situations that allow obtaining a large amount of data over a surface or a…

Instrumentation and Methods for Astrophysics · Physics 2016-08-26 Sampsa Pursiainen , Mikko Kaasalainen

Dielectric tensor tomography (DTT) enables the reconstruction of three-dimensional (3D) dielectric tensors, which provides a physical measure of 3D optical anisotropy. Herein, we present a cost-effective and robust method for DTT…

Optics · Physics 2022-12-14 Juheon Lee , Seungwoo Shin , Herve Hugonnet , Yongkeun Park

We present preliminary results from our investigation into using an 'inside-out' velocity space for creating a Doppler tomogram. The aim is to transpose the inverted appearance of the Cartesian velocity space used in normal Doppler…

Solar and Stellar Astrophysics · Physics 2015-03-17 Enrico J. Kotze , Stephen B. Potter

One objective of the Polstar spectropolarimetry mission is to characterize the degree of nonconservative mass transfer that occurs at various stages of binary evolution, from the initial mass reversal to the late Algol phase. The proposed…

Multiphoton microscopy (MPM) has gained enormous popularity over the years for its capacity to provide high resolution images from deep within scattering samples1. However, MPM is generally based on single-point laser-focus scanning, which…

Optics · Physics 2018-12-14 Devin R. Beaulieu , Ian G. Davison , Thomas G. Bifano , Jerome Mertz

In dynamic tomography the object undergoes changes while projections are being acquired sequentially in time. The resulting inconsistent set of projections cannot be used directly to reconstruct an object corresponding to a time instant.…

Image and Video Processing · Electrical Eng. & Systems 2024-01-30 Berk Iskender , Marc L. Klasky , Yoram Bresler

The observation of the polarization emerging from a rotating star at different phases opens up the possibility to map the magnetic field in the stellar surface thanks to the well-known Zeeman Doppler Imaging. When the magnetic field is…

Solar and Stellar Astrophysics · Physics 2015-06-05 M. J. Martínez González , A. Asensio Ramos

The parabolic structure of the secondary or conjugate spectra of pulsars is often the result of isolated one-dimensional (or at least highly anisotropic) lenses in the ISM. The curvature of these features contains information about the…

Instrumentation and Methods for Astrophysics · Physics 2023-07-11 Daniel Baker , Walter Brisken , Marten H. van Kerkwijk , Robert Main , Ue-Li Pen , Tim Sprenger , Olaf Wucknitz

It is known that stellar differential rotation can be detected by analyzing the Fourier transform of spectral line profiles, since the ratio of the 1st- and 2nd-zero frequencies is a useful indicator. This approach essentially relies on the…

Solar and Stellar Astrophysics · Physics 2020-02-19 Yoichi Takeda

Context. Magnetic fields are important to the dynamics of many astrophysical processes and can typically be studied through polarization observations. Polarimetric interferometry capabilities of modern (sub)millimeter telescope facilities…

Instrumentation and Methods for Astrophysics · Physics 2020-04-08 Boy Lankhaar , Wouter Vlemmings

A new measuring technique dedicated to bubble velocity and size measurements in complex bubbly flows such as those occurring in bubble columns is proposed. This sensor combines the phase detection capability of a conical optical fiber, with…

Fluid Dynamics · Physics 2021-09-17 Anthony Lefebvre , Yann Mezui , Martin Obligado , Stéphane Gluck , Alain Cartellier

A velocity-map-imaging spectrometer is demonstrated to characterize the normalized transverse emittance of photoemitted electron bunches. The two-dimensional (2D) projected velocity distribution images of photoemitted electrons are recorded…

Here we present a number of improvements to weak lensing 3D power spectrum analysis, 3D cosmic shear, that uses the shape and redshift information of every galaxy to constrain cosmological parameters. We show how photometric redshift…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 T. D. Kitching , A. F. Heavens , L. Miller

The modern Doppler Imaging (DI) technique allows the reconstruction of different stellar surface structures based on accurate calculation of spectra of specific intensity. New applications like the mapping of the magnetic field vector put…

Astrophysics · Physics 2007-05-23 N. Piskunov

Circumbinary planets - planets that orbit both stars in a binary system - offer the opportunity to study planet formation and orbital migration in a different environment compare to single stars. However, despite the fact that > 90% of…

We theoretically investigate the optical rotational Doppler Effect using modal expansion method. We find that the frequency shift content is only determined by the surface of spinning object and the reduced Doppler shift is linear to the…

Optics · Physics 2015-07-16 Hailong Zhou , Jianji Dong , Pei Zhang , Xinliang Zhang

Tomography can be used to reveal internal properties of a 3D object using any penetrating wave. Advanced tomographic imaging techniques, however, are vulnerable to both systematic and random errors associated with the experimental…

Numerical Analysis · Mathematics 2019-02-08 Anthony P. Austin , Zichao Wendy Di , Sven Leyffer , Stefan M. Wild

Time-resolved H-alpha spectra of magnetically-active interacting binaries have been used to create 3D Doppler tomograms by means of the Radioastronomical Approach. This is the first 3D reconstruction of Beta Per, with RS Vul for comparison.…

Solar and Stellar Astrophysics · Physics 2015-06-11 Mercedes T. Richards , Michail I. Agafonov , Olga I. Sharova
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