# Generalized optical theorems for the reconstruction of Green's function of an inhomogeneous elastic medium.

@article{Margerin2011GeneralizedOT, title={Generalized optical theorems for the reconstruction of Green's function of an inhomogeneous elastic medium.}, author={Ludovic Margerin and Haruo Sato}, journal={The Journal of the Acoustical Society of America}, year={2011}, volume={130 6}, pages={ 3674-90 } }

This paper investigates the reconstruction of elastic Green's function from the cross-correlation of waves excited by random noise in the context of scattering theory. Using a general operator equation-the resolvent formula-Green's function reconstruction is established when the noise sources satisfy an equipartition condition. In an inhomogeneous medium, the operator formalism leads to generalized forms of optical theorem involving the off-shell T-matrix of elastic waves, which describes…

## 14 Citations

Mean-field T-matrix approach to elastic wave scattering by small and point-like objects

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The T-matrix of a small inclusion embedded in a homogeneous matrix is calculated for vector elastic waves. The theory relies on an approximation of the local stress and momentum inside the inclusion…

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Far-field scattering model for wave propagation in random media.

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The perturbed wave number in the developed model does not depend explicitly on the crystallite elastic properties even for arbitrary crystallographic symmetry; it depends on two nondimensional scattering elastic parameters and the macroscopic ultrasonic velocity which provides an advantage for potential schemes for inversion from attenuation to material microstructure.

Extended optical theorem in isotropic solids and its application to the elastic radiation force

- Physics
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In this article, we derive the extended optical theorem for the elastic-wave scattering by a spherical inclusion (with and without absorption) in a solid matrix. This theorem expresses the extinction…

Generalized Optical Theorem and Point Sources

- MathematicsLight & Engineering
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A simple derivation of the general form of the optical theorem (GOT) is given for the case of a conservative scatterer in a homogeneous lossless medium, suitable for describing point sources and an…

Diffusion approximation with polarization and resonance effects for the modelling of seismic waves in strongly scattering small-scale media

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SUMMARY This paper presents an analytical study of the multiple scattering of seismic waves by a collection of randomly distributed point scatterers. The theory assumes that the energy envelopes are…

Boundary eﬀect on multiple scattering of elastic waves in a half-space

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- 2015

The scattering of elastic waves is studied in the vicinity of a vacuum-medium boundary. The Green’s function for a half-space is re-derived within the mixed 2D-Fourier representation, which is…

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With the more widespread introduction of multicomponent recording devices in land and marine ocean-bottom seismic acquisition, elastic imaging may become mainstream in coming years. We have derived…

Absence of Geometrical Regime for Impedance‐Type Elastic Scatterers

- MathematicsBulletin of the Seismological Society of America
- 2018

In wave physics, the geometrical limit is defined as a propagation regime where the scattering 5 cross-section (cid:27) of an object becomes independent of its internal structure and tends to twice…

A unified optical theorem for scalar and vectorial wave fields.

- Mathematics, PhysicsThe Journal of the Acoustical Society of America
- 2012

A unified optical theorem is derived that encompasses the separate versions for scalar and vectorial waves that holds for scattering by anisotropic elastic and piezoelectric scatterer as well as bianisotropic (non-reciprocal) EM scatterers.

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