1. RFQ Structural Mods Scott Lawrie

2. Vacuum Pump Flange Vacuum Flange Coolant Manifold Cooling Pockets Milled Into Vanes Potentially Bolted Together Tuner & Coupler Ports Vanes

3. Increased Pumping Area Original design: Twelve 12mm wide slots Pumping area = 7045 mm 2 Modified design: Four 25mm wide slots Pumping area = 9749 mm 2 (43% greater)

4. Simulation Bodies 25mm 12mm Section of pump’s debris-catching grill Inter-vane vacuum Bulk quadrant vacuum Pumping slot vacuum

5. Magnetic Field Results B-field plot path

6. ≈1W total heat ≈10mW total heat Turbo-pump grill position B-field along plot path

7. Because B-field is not uniform, neither is heat load. Therefore 1W is an over-estimate, but let’s not push it! Magnetic Field Across Grill Assume 1mm pitch, square wire grill

8. Frequency varies with RFQ length Mode Frequency / MHz Resonant Frequency: Superfish

9. Present geometry Q = 12463 Shunt Impedance = 2830 MΩ/m Power/Quadrant/cm = 186 W

10. Increased quadrant radius to bring on tune Q = 12749 Shunt Impedance = 3022 MΩ/m Power/Quadrant/cm = 174 W

11. Reduced quadrant radius but increased vane width Q = 11504 Shunt Impedance = 2308 MΩ/m Power/Quadrant/cm = 228 W

13. 20mm wide vanes allow: 1.More material, so greater thermal conductivity and strength 2.Easier to machine straight edges 3.More room for cooling pocket penetration toward vane tip