Coupling between radiative transport and diffusion approximation for enhanced near-field photon-migration modeling based on transient photon kinetics

Radiative transport for two-photon light

The propagation of light in disordered media, including clouds, colloidal suspensions, and biological tissues, is generally considered within the framework of classical optics [1]. However, recent experiments have demonstrated the existence of novel effects in multiple light scattering, in which the quantized nature of the electromagnetic field is manifest. These include (i) the transport of qu...

Diffusion based photon mapping

Comparison of finite-difference transport and diffusion calculations for photon migration in homogeneous and heterogeneous tissues.

We analyse the limits of the diffusion approximation to the time-independent equation of radiative transfer for homogeneous and heterogeneous biological media. Analytical calculations and finite-difference simulations based on diffusion theory are compared with discrete-ordinate, finite-difference transport calculations. The influence of the ratio of absorption and transport scattering coeffici...

Photon migration in turbid media using a cumulant approximation to radiative transfer.

A photon transport model for light migration in turbid media based on a cumulant approximation to radiative transfer is presented for image reconstruction inside an infinite medium or a bounded medium with a planar geometry. This model treats weak inhomogeneities through a Born approximation of the Boltzmann radiative transfer equation and uses the second-order cumulant solution of photon densi...

Radiative production of invisible charginos in photon-photon collisions

If in a supersymmetric model, the lightest chargino is nearly degenerate with the lightest neutralino, the former can decay into the latter alongwith a soft pion (or a lepton-neutrino pair). Near degeneracy of the chargino and neutralino masses can cause the other decay products (the pion or the lepton) to be almost invisible. Photon-photon colliders offer a possibility of clean detection of su...