>The light would be absorded on the light source side of the dust particle, and if it is then retransmitted as say infrared it would transmitted mainly in the direction that it was absorbed, with only a little of it at 90 degs to the absorption direction i.e. none of it is retransmitted in the direction it was originally travelling.
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>You have to remember that infrared exchanges occur in the nano second timescale which gives little or no time for conductive thermal transfer accross the particle, and remember the entropic process will normalize the area asap.

I don't think so. A particle, or group of gas atoms, gets heated up, and will eventually emit thermal radiation. There is no reason why it should "remember" where the energy came from in the first place.

As to the nanosecond timescale... Well, I guess that would depend on the size of the particle. If a particle is big enough, it may take a while to heat up, and to cool down again through radiation. For a gas atom, it may indeed be nanoseconds, if not less.

>I beg to differ on the dissipation rates, I will see if I can find a reference for you

I was referring to the total energy received vs. transmitted. This simply follows from the law of conservation of energy - unless of course part of the incoming energy gets converted, say, to chemical energy.