In order to improve our extraction of asymmetries in at low E' (or x) I created a composite structure function class which uses F1F209 and the NMC95 fit. F1F209 is valid for Q2<10 (GeV/c)^2 and W<3GeV and NMC95 is a fit to DIS data.
In order to smoothly average them I define a region where a weighted average is taken. This region for W starts at W=2.3 up to 2.8 GeV (because F1F209 is not that great at W=3) and for Q2 it is from 8 to 10 (GeV/c)^2. The corner is handled by using the weight function (x + y - x*y) which has the proper boundary conditions to patch the linear weight function for the to previous regions.
Above is a 2D plot of F2p vs x and Q^2. Below is a comparison to data of F2p. Note the transition from the red curve to blue curve around x = 0.35.
When F1F209 is used to get the nuclear cross section, it returns the proper structure function per nucelus. When NMC95 is used, the EMC effect fit (steve rocks's fit improved version) is used along with the calculated deuteron structure function. Below you can see the deuteron structure function and the emc cross section ratio. The region is clear when compared to the plot of the EMC fit (red).
It is interesting to see the effect that radiative corrections have on the EMC ratio. However, at very low E' the approximations be come less accurate.
![[ICO]](/icons/blank.gif){kind=icon} | Name | Last modified | Size | Description |
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![[PARENTDIR]](/icons/back.gif){kind=icon} | Parent Directory | - | ||
![[IMG]](/icons/image2.gif){kind=icon} | DIS_nuclear_compare.png | 2015-01-09 17:56 | 24K | |
| DIS_nuclear_compare2..> | 2015-01-09 17:56 | 22K | |
| F1pCompare2.png | 2015-01-09 17:56 | 41K | |
| F2_Ratios.png | 2015-01-09 17:56 | 15K | |
| F2_Ratios_2.png | 2015-01-09 17:56 | 25K | |
| F2_Ratios_3.png | 2015-01-09 17:56 | 32K | |
| F2d.png | 2015-01-09 17:56 | 46K | |
| F2pCompare.png | 2015-01-09 17:56 | 43K | |