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Related papers: Inversion of the Weighted Spherical Mean

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We prove the Plancherel formula for spherical Schwartz functions on a reductive symmetric space. Our starting point is an inversion formula for spherical smooth compactly supported functions. The latter formula was earlier obtained from the…

Representation Theory · Mathematics 2007-05-23 E. P. van den Ban , H. Schlichtkrull

We investigate a generalized spherical means operator, viz. generalized spherical mean Radon transform, acting on radial functions. We establish an integral representation of this operator and find precise estimates of the corresponding…

Classical Analysis and ODEs · Mathematics 2018-11-06 Óscar Ciaurri , Adam Nowak , Luz Roncal

The article suggests a new approach what is called a consistency method for the inversion of the spherical Radon transform in 2D with detectors on a line. It is known that there is not an exact inversion formula in 2D. By means of the…

Numerical Analysis · Mathematics 2017-05-31 Rafik Aramyan

The paper surveys recent progress in establishing uniqueness and developing inversion formulas and algorithms for the thermoacoustic tomography. In mathematical terms, one deals with a rather special inverse problem for the wave equation.…

Analysis of PDEs · Mathematics 2009-02-02 M. Agranovsky , P. Kuchment , L. Kunyansky

Spin-weighted spherical functions provide a useful tool for analyzing tensor-valued functions on the sphere. A tensor field can be decomposed into complex-valued functions by taking contractions with tangent vectors on the sphere and the…

General Relativity and Quantum Cosmology · Physics 2023-08-30 Michael Boyle

We study inversion of the spherical Radon transform with centers on a sphere (the data acquisition set). Such inversions are essential in various image reconstruction problems arising in medical, radar and sonar imaging. In the case of…

Classical Analysis and ODEs · Mathematics 2017-09-25 Gaik Ambartsoumian , Rim Gouia-Zarrad , Venkateswaran P. Krishnan , Souvik Roy

The spherical mean transform associates to a function $f$ its integral averages over all spheres. We consider the spherical mean transform for functions supported in the unit ball $\mathbb{B}$ in $\mathbb{R}^n$ for odd $n$, with the centers…

Classical Analysis and ODEs · Mathematics 2024-06-25 Divyansh Agrawal , Gaik Ambartsoumian , Venkateswaran P. Krishnan , Nisha Singhal

An index transform, involving the square of Whittaker's function is introduced and investigated. The corresponding inversion formula is established. Particular cases cover index transforms of the Lebedev type with products of the modified…

Classical Analysis and ODEs · Mathematics 2025-04-01 Semyon Yakubovich

The goal of inversion is to estimate the model which generates the data of observations with a specific modeling equation. One general approach to inversion is to use optimization methods which are algebraic in nature to define an objective…

Geophysics · Physics 2015-06-02 August Lau , Chuan Yin

Data augmentation in feature space is effective to increase data diversity. Previous methods assume that different classes have the same covariance in their feature distributions. Thus, feature transform between different classes is…

Computer Vision and Pattern Recognition · Computer Science 2020-08-05 Yuke Zhu , Yan Bai , Yichen Wei

We derive inversion formulas involving orthogonal polynomials which can be used to find coefficients of differential equations satisfied by certain generalizations of the classical orthogonal polynomials. As an example we consider special…

Classical Analysis and ODEs · Mathematics 2007-05-23 Roelof Koekoek

We consider the spherical mean generated by a multidimensional generalized translation and general Euler-Poisson-Darboux equation corresponding to this mean. The Asgeirsson property of solutions of the ultrahyperbolic equation that includes…

Classical Analysis and ODEs · Mathematics 2017-03-21 Elina Shishkina

We describe the range of a restricted spherical mean transform, which sends a function supported inside a closed ball in a hyperbolic space to its mean values on the geodesics spheres centered at the boundary of the ball. The description…

Differential Geometry · Mathematics 2011-09-28 Linh V. Nguyen

The windowed ray transform is a natural generalization of the "Analytic-Signal Transform" which is developed to extend arbitrary functions from $\RR^n$ to $\CC^n$. We present several inversion formulas here.

Functional Analysis · Mathematics 2013-11-25 Sunghwan Moon

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

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

We calculate the Fourier transform of a spherically symmetric exponential function. Our evaluation is much simpler than the known one. We use the polar coordinates and reduce the Fourier transform to the integral of a rational function of…

Classical Analysis and ODEs · Mathematics 2019-01-01 Hideshi Yamane

A transformation based on mean curvature is introduced which morphs triangulated surfaces into round spheres.

Graphics · Computer Science 2016-08-16 Dimitris Vartziotis

In the present paper, a construction of spin weighted spherical wavelets is presented. It is based on approximate identities, the wavelets are defined for a continuous set of parameters, and the wavelet transform is invertible directly by…

Functional Analysis · Mathematics 2018-04-16 Ilona Iglewska-Nowak

We derive an explicit inversion algorithm for the spherical Radon transform in odd dimensions with partial radial data. We prove that the reconstruction of the unknown function can be reduced to solving ordinary differential equations,…

Analysis of PDEs · Mathematics 2026-01-27 Pradipta Chatterjee , Venkateswaran P. Krishnan , Abhilash Tushir