As a result of the failure of the ratios R1 and R3 to produce a constant relationship, an alternate means of relating the elastic monitor counts to the beam current was considered.
If a Faraday cup was placed between the MD1 and ED1, it would be
possible to take beam current readings while simultaneously recording
elastic monitor counts. This would provide a direct and continuous
relationship between beam current and elastic monitor counts. Since
not all of the beam continues past the first charge slit, it
would be necessary to take Faraday cup readings for each charge state,
then sum the readings and compare them to the elastic monitor count
for the same time period.
If carried out for every new beam energy, this procedure would provide the correct calibration constant even when the elastic cross section deviates from pure Rutherford scattering.
