45 citations · 238 across the 51 of their papers we have counts for
7 papers · 1 filter
The Light Ray transform in Stationary and Static Lorentzian geometries
Ali Feizmohammadi, Joonas Ilmavirta, Lauri Oksanen
Given a Lorentzian manifold, the light ray transform of a function is its integrals along null geodesics. This paper is concerned with the injectivity of the light ray transform on…
Unique continuation of the normal operator of the X-ray transform and applications in geophysics
Joonas Ilmavirta, Keijo Mönkkönen
We show that the normal operator of the X-ray transform in , , has a unique continuation property in the class of compactly supported distributions. This imm…
Torus computed tomography
Joonas Ilmavirta, Olli Koskela, Jesse Railo
We present a new computed tomography (CT) method for inverting the Radon transform in 2D. The idea relies on the geometry of the flat torus, hence we call the new method Torus CT.…
Optimal recovery of a radiating source with multiple frequencies along one line
Tommi Brander, Joonas Ilmavirta, Petteri Piiroinen +1
We study an inverse problem where an unknown radiating source is observed with collimated detectors along a single line and the medium has a known attenuation. The research is moti…
Recovery of time dependent coefficients from boundary data for hyperbolic equations
Ali Feizmohammadi, Joonas Ilmavirta, Yavar Kian +1
We study uniqueness of the recovery of a time-dependent magnetic vector-valued potential and an electric scalar-valued potential on a Riemannian manifold from the knowledge of the…
Determination of a compact Finsler manifold from its boundary distance map and an inverse problem in elasticity
Maarten V. De Hoop, Joonas Ilmavirta, Matti Lassas +1
We prove that the boundary distance map of a smooth compact Finsler manifold with smooth boundary determines its topological and differentiable structures. We construct the optimal…