I think there is a lot of confusion over the method that i used for fitting, So I should make it clear here. In this method I fit the first shell by taking into account only first shell R range i.e. 1.5 - 2.7. Then after getting a nice fit for the first shell, I extract its parameters and make them set in Artemis. Then I include the second shell by increasing R range to 1.5 - 3.6. In the same manner I fit the first three shells of copper foil and the parameters I got for them are reasonably good.

The problem of high SO2 only lies with one of my foil data which is not as good as other data. For other good data I got SO2 value for second shell within the exceptable limit.

One more thing I want to say is that we can check the corelation between different parameters of shells by making them guess during any step of the fitting e.g. during the fitting of second shell we can make any parameter of the first shell to vary and check its corelation with them.

But if I am counting the first shell data twice, I will include only second shell R range after first shell fit.I think it will not make any difference to results. If yes please tell me the reasons.