A Marchenko equation for acoustic inverse source problems.

Area of Science:

• Acoustics
• Medical Imaging
• Seismology
• Wave Phenomena

Background:

• Inferring complex media structure from acoustic wave observations is crucial across multiple scientific disciplines.
• Conventional methods like backpropagation require complete boundary observations and detailed medium models, which are often impractical.
• Strong medium contrasts and scattering can introduce artifacts and limit the accuracy of traditional approaches.

Purpose of the Study:

• To develop a novel methodology for determining acoustic source distributions within a volume using limited external observations.
• To address the limitations of traditional backpropagation methods in scenarios with incomplete boundary data and unknown medium properties.
• To enhance the accuracy and applicability of acoustic source localization in complex and scattering environments.

Main Methods:

• Derivation of a solution from the multidimensional Marchenko equation.
• Utilizing a single observation boundary for data acquisition.
• Incorporating multi-offset ultrasound reflection data at the observation boundary.
• Validation using one-dimensional synthetic data from a photoacoustic imaging experiment.

Main Results:

• Successful recovery of acoustic source distributions in the presence of sharp density perturbations.
• Demonstration of the method's robustness against significant scattering effects.
• Overcoming artifacts typically associated with strong medium contrasts in conventional methods.

Conclusions:

• The proposed Marchenko-equation-derived method offers a robust alternative for acoustic source localization.
• The technique effectively handles complex media and scattering, requiring only a single observation boundary and no prior medium model.
• This approach significantly advances capabilities in acoustic imaging and inverse problems within challenging environments.