B2016_target_analysis
From run 2085 fitted spectrum in SU ring 13 to three normalized Gaussians:
FCN=35.894 FROM MINOS STATUS=SUCCESSFUL 696 CALLS 7998 TOTAL
EDM=8.93933e-07 STRATEGY= 1 ERROR MATRIX ACCURATE
EXT PARAMETER STEP FIRST
NO. NAME VALUE ERROR SIZE DERIVATIVE
1 p0 2.30019e+04 1.25554e+03 -5.40050e-05 -5.38960e-02
2 p1 3.86851e+02 1.87250e+00 -1.62580e-04 3.17564e-02
3 p2 2.73188e+01 1.37784e+00 -2.36937e-05 4.89640e-02
4 p3 6.38637e+03 2.73318e+03 3.91919e-04 2.31960e-02
5 p4 4.41634e+02 3.36936e+00 1.57733e-03 -2.56088e-02
6 p5 1.45273e+01 4.69849e+00 6.79937e-04 -7.78675e-02
7 p6 8.18498e+03 1.75138e+03 -1.07339e-03 -5.27947e-02
8 p7 4.71231e+02 1.87020e+00 -4.27803e-05 -6.72797e-02
9 p8 1.09077e+01 9.67694e-01 9.67694e-01 -1.14570e-01
Parameters are amplitude, mean, sigma. Bin width was 4keV.
Peak to the left is assumed to be boron. Peak to the right is backing carbon.
Assuming a backing thickness of 4µg/cm² ± 10%. Assuming Rutherford scattering this gives a thickness of 16 ± 4 µg/cm².
The main uncertainty is the amplitude of the backing peak.