Experimental determination of Mean free path.

[hyperickz]

Is there any direct experiment to determine the value of mean free path(not the distribution) of a gas molecule?

 

[Quantum Defect]

Is there any direct experiment to determine the value of mean free path(not the distribution) of a gas molecule?

There are lots of experimental methods to determine the average mean free path of a large collection of molecules, but I gather that this is not what you have in mind.

I suspect that you could devise an experiment using very low partial pressures of atoms that you are able to continually optically excite where you might be able to somehow infer some information about the mean free path. People have done analagous experiments in the liquid phase. People trap atoms with lasers, and you must be abel to see collisional effects, e.g. as you are laser cooling some atoms in a trap.