BPM for new AD Electron Cooler Main parameters

BPM for new AD Electron Cooler

Main parameters § Maximum energy: 80 ke. V § Magnetic field in drift: 600 G § Electron beam energy: 68. 125 ke. V § Expansion factor: 2 § Antiproton beam momentum: 500 Me. V/c § Beam radius in drift: 2. 5 cm § Accelerating voltage: 68. 808 k. V § Ne 7. 9 x 1013 m-3 § Relativistic beta: 0. 471 § Drift solenoid length: 1. 5 m § Maximum electron current: 3. 5 A § Cooler orientation: horizontal § Cathode radius: 1. 25 cm § Vacuum chamber diameter: 140 mm § Magnetic field in gun: 2400 G • Cooling at a higher antiproton momentum (≤ 500 Me. V/c) • Horizontal orientation • Electrostatic plates in each toroid (? ). • NEG coated vacuum chambers. • Ramping of the expansion solenoid to adapt the electron beam size during cooling. • New solenoid design using pancakes and iron bars for the return-flux. • Compact orbit correctors (as used on ELENA).

Potential gains Present cooler New cooler Gain Max Ee (ke. V) for cooling Corresponding beam momentum (Me. V/c) 300 500 Gun perveance (m. P) 0. 58 2. 6 Ie at 100 Me. V/c (m. A) 105 470 1 2 Expansion factor Electron beam transverse temperature (me. V) 27 68 Shorter deceleration ramp from 2 Ge. V/c. Smaller initial emittances. Faster cooling with lower equilibrium emittances. Four times faster cooling at extraction energy. Four times reduction in electron beam transverse temperature resulting in faster cooling and smaller equilibrium emittances. 100 25 Bt/Bl 1. 00 E-03 1. 00 E-04 Electron beam losses Vacuum pressure in cooling section (torr) 1. 00 E-03 1. 00 E-04 Better collector efficiency with electrostatic plates in the toroid magnets. Pressure reduction with extra pumping from NEG. Less outgassing from 4. 00 E-12 secondary beam loss. Less blow-up due to vacuum. 2. 00 E-11

Momentum β Ee (ke. V) Ie (A) Ne (x 1013 m-3) I (for 3 x 107 pbars) Frev (k. Hz) 500 Me. V/c 0. 471 68. 8 3. 5 7. 9 3. 72 μA 773 Resolution : 0. 1 mm Precision : 0. 1 mm Time resolution : 10 ms Frev from 1. 589 to 0. 174 MHz 300 Me. V/c 0. 305 26. 1 2. 5 8. 7 2. 55 μA 500 100 Me. V/c 0. 106 3. 16 0. 4 4. 0 0. 84 μA 174 Length : 300 mm Inner diameter : 145 mm DN 200 flange Bakeout at 250 °C Vacuum : 4 x 10 -12 torr

Timeline Installation of new electron cooler on the AD planned for 2024 The complete system will be mounted and tested in building 236 in 2023 The BPM system should be produced and laboratory tested by the end of 2022