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Related papers: Inversion and Symmetries of the Star Transform

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The evolution of close binary stars in mass asymmetry (transfer) coordinate is considered. The conditions for the formation of stable symmetric binary stars are analyzed. The role of symmetrization of asymmetric binary star in the…

Solar and Stellar Astrophysics · Physics 2019-02-20 V. V. Sargsyan , H. Lenske , G. G. Adamian , N. V. Antonenko

The spherical Radon transform (SRT) is an integral transform that maps a function to its integrals over concentric spherical shells centered at specified sensor locations. It has several imaging applications, including synthetic aperture…

Image and Video Processing · Electrical Eng. & Systems 2024-02-27 Luke Lozenski , Refik Mert Cam , Mark A. Anastasio , Umberto Villa

A star anagram is a rearrangement of the letters of one word to produce another word where no letter retains its original neighbors. These maximally shuffled anagrams are rare, comprising only about 5.7% of anagrams in English. They can…

Other Computer Science · Computer Science 2025-07-08 Jason Parker , Dan Barker

In recent years, Radon type transforms that integrate functions over various sets of ellipses/ellipsoids have been considered in SAR, ultrasound reflection tomography, and radio tomography. In this paper, we consider the transform that…

Functional Analysis · Mathematics 2013-10-07 Sunghwan Moon

High precision photometry and spectroscopy of low-mass stars reveal a variety of properties standard stellar evolution cannot predict. Rotation, an essential ingredient of stellar evolution, is a step towards resolving the discrepancy…

Astrophysics · Physics 2007-11-15 D. Brown , M. Salaris , S. Cassisi , A. Pietrinferni

In this paper, we investigate the relations between the Radon and weighted divergent beam and cone transforms. Novel inversion formulas are derived for the latter two. The weighted cone transform arises, for instance, in image…

Numerical Analysis · Mathematics 2016-12-23 Peter Kuchment , Fatma Terzioglu

The transform considered in the paper integrates a function supported in the unit disk on the plane over all circles centered at the boundary of this disk. Such circular Radon transform arises in several contemporary imaging techniques, as…

General Mathematics · Mathematics 2007-05-23 Gaik Ambartsoumian , Peter Kuchment

We revisit the standard representation of the (inverse) Radon transform which is well-known in the mathematical literature. We extend this representation to the case involving the parton distributions. We have found the new additional…

High Energy Physics - Phenomenology · Physics 2019-12-04 I. V. Anikin , L. Szymanowski

The spherical Radon-Dunkl transform $R_\kappa$, associated to weight functions invariant under a finite reflection group, is introduced, and some elementary properties are obtained in terms of $h$-harmonics. Several inversion formulas of…

Classical Analysis and ODEs · Mathematics 2009-03-04 Zhongkai Li , Futao Song

The cone-beam transform consists of integrating a function defined on the three-dimensional space along every ray that starts on a certain scanning set. Based on Grangeat's formula, Louis [2016, Inverse Problems 32 115005] states…

Numerical Analysis · Mathematics 2021-08-13 Michael Quellmalz , Ralf Hielscher , Alfred K. Louis

An explicit series solution is proposed for the inversion of the spherical mean Radon transform. Such an inversion is required in problems of thermo- and photo- acoustic tomography. Closed-form inversion formulae are currently known only…

Analysis of PDEs · Mathematics 2009-11-13 Leonid Kunyansky

This paper reviews the physics of stars, the type, structure, evolution and stability. Simple thermodynamics and statistical mechanics are used to show the inner working of white dwarf and neutron stars. The major concentration of the paper…

Popular Physics · Physics 2024-03-21 Anuj Chaudhri

Quantitative thermodynamical, dynamical and magnetic properties of the solar and stellar plasmas are obtained by interpreting their emergent non-polarized and polarized spectrum. This inference requires the selection of a set of spectral…

Solar and Stellar Astrophysics · Physics 2016-05-25 A. Asensio Ramos , J. de la Cruz Rodriguez , M. J. Martinez Gonzalez , A. Pastor Yabar

Hyperplane is a set of non-injectivity of the spherical Radon transform (SRT) in the space of continuous functions in R^d. In this article, for the reconstruction of an unknown function f from C(R^3) (the support can be non-compact), using…

Classical Analysis and ODEs · Mathematics 2024-04-09 Rafik Aramyan

High precision photometry and spectroscopy of low-mass stars reveal a variety of properties standard stellar evolution cannot predict. Rotation, an essential ingredient of stellar evolution, is a step towards resolving the discrepancy…

Astrophysics · Physics 2009-11-13 D. Brown , M. Salaris

The X-ray transform on a compact symmetric space M is here inverted by means of an explicit inversion formula. The proof uses the conjugacy of the minimal closed geodesics in M and of the maximally curved totally geodesic spheres in M,…

Representation Theory · Mathematics 2007-05-23 Sigurdur Helgason

Any even function defined on 2-sphere is reconstructed from its integrals over big circles by means of the classical Funk formula. For the non-geodesic Funk transform on the sphere of arbitrary dimension, there is the explicit inversion…

Functional Analysis · Mathematics 2017-11-29 Victor Palamodov

In image reconstruction there are techniques that use analytical formulae for the Radon transform to recover an image from a continuum of data. In practice, however, one has only discrete data available. Thus one often resorts to sampling…

Functional Analysis · Mathematics 2011-08-30 Isaac Pesenson , Eric Grinberg

Radial differential rotation is an important parameter for stellar dynamo theory and for understanding angular momentum transport. We investigate the potential of using a large number of similar stars simultaneously to constrain their…

Solar and Stellar Astrophysics · Physics 2016-02-03 Hannah Schunker , Jesper Schou , Warrick Ball , Martin Bo Nielsen , Laurent Gizon

In this work we consider the Conical Radon Transform, which integrates a function on $\R^n$ over families of circular cones. Transforms of this type are known to arise naturally as models of Compton camera imaging and single-scattering…

Functional Analysis · Mathematics 2023-04-27 Weston Baines