Analysis of a Breit-Wigner spectrum
In the following table you can see experimental data of the cross section as a function of energy for neutron scattering:
The cross-section as a function of energy can be described as the Breit-Wigner function:
where Er is the resonance energy (position of the maximum), and γ the width at half-maximum height.
Objective: to determine the values of Er and γ from the experimental data. Here, three possible methods are shown: Lagrange Interpolators, Cubic Splines and Least Squares.