Determine the structure function

The structure function can be directly derived from the cross section if you have a an approximate idea of the value of R. I think it has a Q² dependance to be exact but it can be approximated as about [0.06 +/- 6]/Q² There are various papers on how to get these structure functions from other sources: http://arxiv.org/pdf/0805.3116v2.pdf and then there is R.G. Roberts "The Structure of the Proton" - pretty much THE handbook for information about any kinds of functions and properties relating to sub components of the proton.