Linh V. Nguyen

How strong are streak artifacts in limited angle computed tomography

In this article, we consider the limited angle problem in computed x-ray tomography. A common practice is to use the filtered back projection with the limited data. However, this practice has been shown to introduce the artifacts along some straight lines. In this work, we characterize the strength of these artifacts.

A dissipative time reversal technique for photoacoustic tomography in a cavity

We consider the inverse source problem arising in thermo- and photoacoustic tomography. It consists in reconstructing the initial pressure from the boundary measurements of the acoustic wave. Our goal is to extend versatile time reversal techniques to the case when the boundary of the domain is perfectly reflecting, effectively turning the domain into a reverberant cavity. Standard time reversal works only if the solution of the direct problem decays in time, which does not happen in the setup we consider. We thus propose a novel time reversal technique with a nonstandard boundary condition. The error induced by this time reversal technique satisfies the wave equation with a dissipative boundary condition and, therefore, decays in time. For larger measurement times, this method yields a close approximation; for smaller times, the first approximation can be iteratively refined, resulting in a convergent Neumann series for the approximation.

On Artifacts in Limited Data Spherical Radon Transform: Flat Observation Surfaces

In this paper, we characterize the strength of the reconstructed singularities and artifacts in a reconstruction formula for limited data spherical Radon transform. Namely, we assume that the data is available only on a closed subset

Analysis of Iterative Methods in Photoacoustic Tomography with Variable Sound Speed

\Gamma

On artifacts in limited data spherical Radon transform: curved observation surface

of a hyperplane in

Motion Estimation and Correction in Photoacoustic Tomographic Reconstruction

\mathbb{R}^n

Range description for a spherical mean transform on spaces of constant curvature

(

Generalized impedance boundary conditions for strongly absorbing obstacle: The full wave equation

n=2,3

Iterative methods for photoacoustic tomography in attenuating acoustic media

). We consider a reconstruction formula studied in some previous works, under the assumption that the data is only smoothed out to a finite order

Analysis of the Linearized Problem of Quantitative Photoacoustic Tomography

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