1. 45° Tandem Parallel Plate Analyser
SIMION Project
45° Tandem Parallel Plate Analyser
Louise Belshaw
Spiros Divanis
Patrik Gunacker
Peter Herczku

2. PPA ONE IONS, ELECTRONS IONS ELECTRONS PPA TWO
SIMION Project: Tandem PPA Analyser
PPA ONE
IONS, ELECTRONS
IONS
ELECTRONS
A bit of chat about why we want to simulate a tandem ppa – want to look at electrons on axis, but need to get rid of ions
PPA TWO

3. ` Tandem Parallel Plate Analyser:
SIMION Project: Tandem PPA Analyser `
Tandem Parallel Plate Analyser:
Build a simple tandem PPA, consisting of two PPAs placed at 90°.
Investigate required voltages and angles of acceptance.
Add an Einzel lens before the input slit of PPA1, and place another between the exit of PPA1 and the entrance of PPA2.
How does this change our results?

4. ` Simple Tandem PPa PPA ONE PPA TWO
SIMION Project: Tandem PPA Analyser
SIMION Project: Tandem PPA Analyser `
Simple Tandem PPa
PPA ONE
SIMION results
For this PPA, f = 0.6
Electrons of KE = 1000 eV
Expect required V = -600 V
Used: -597 V
Required Deflecting voltage:
Acceptance Solid Angle:
α = ± 3°
β = ± 5°
Ω = 4αβ = steradians
Transmission:
Strong angular dependence:
With α = 3, β = 5, T = 0.2 %
α = 1, β = 1, T = 3 %
PPA TWO

5. Simple Tandem PPa Typical Particle Definitions:
SIMION Project: Tandem PPA Analyser
SIMION Project: Tandem PPA Analyser
Simple Tandem PPa
Typical Particle Definitions:

6. Tandem Ppa Without focussing
SIMION Project: Tandem PPA Analyser
Tandem Ppa Without focussing

7. ` Tandem Ppa WiTh Einzel lens EINZEL LENS 1 EINZEL LENS 2
SIMION Project: Tandem PPA Analyser `
Tandem Ppa WiTh Einzel lens
EINZEL LENS 1
EINZEL LENS 2

8. SIMION Project: Tandem PPA Analyser`
Tandem Ppa With Einzel lens

9. Tandem Ppa With Einzel lens
SIMION Project: Tandem PPA Analyser
SIMION Project: Tandem PPA Analyser
Tandem Ppa With Einzel lens
Voltages:
Transmission:
With α = 3, β = 5, T = 5 %
α = 1, β = 1, T = 30 %

10. Tandem Ppa With Deceleration and focussing
SIMION Project: Tandem PPA Analyser `
Tandem Ppa With Deceleration and focussing

11. Tandem Ppa With Deceleration and focussing
SIMION Project: Tandem PPA Analyser `
Tandem Ppa With Deceleration and focussing
Voltages:
Transmission:
With α = 3, β = 5, T = 0.4 %
α = 1, β = 1, T = 9.2 %

12. Transmission comparison
SIMION Project: Tandem PPA Analyser
Transmission comparison
PPA Type
Transmission, α = 3, β = 5
Transmission, α = 1, β = 1
No focussing
0.2 3
Focussing 5 30
Focussing and deceleration
0.4
9.2

13. Thank you for your attention!