March 21, 2017 - Radio-isotope test
Beam requirements
1. What energy or energy range do you want (is this total, kinetic), and if a range what step size or resolution is practically useful?
- We'd like to have kinetic energy at least 18 MeV, and under 18.5 MeV (18.5 preferable), with a resolution (sigma) of at least 20 keV.
2. How well do you need to know the mean energy of #1 (not energy spread), just mean energy?
- 20keV
3. Is energy spread an issue, and if yes - is this value similar to #2?
- Yes.
4. What is the beam spot size or aspect ratio you would like to have at the radiator, and if a limit is important or a range is desired, please say so?
- Under 3x3 mm sigma
5. How well do you need to know the beam size, aspect or profile, maybe this is an issue for your diagnostics?
- Accuracy of beam size and stability about 1 mm
6. How precisely do you need to set the beam position at the radiator, how will you do this?
- 1 mm, use the beam profile scanner just upstream
7. How much position jitter or instability is acceptable, this might be an important point?
- From Pavel: 3x3 mm
- From George: 'Our sample is going to be about 2 mm larger that the beam (assuming Gaussian beam with sigma=3mm). So we can have a small position jitter of 1-1.5 mm, but more than that will mean we are missing the target.'
8. What is the beam intensity you will use at the energies in #1, is this cw or peak?
- 50 uA CW
9. Are there limits on how much beam or beam intensity can be used when setting up on the radiator, e.g. limit so not to contribute to your result?
- Pulsed beam if possible, at a reasonable intensity
10. What else?
- Joe Gubeli mentioned YAG Viewer on the target, so I think this is how we plan to monitor the beam position during the irradiation.