| მთავარი > Efficient transfer of positrons from a buffer-gas-cooled accumulator into an orthogonally oriented superconducting solenoid for antihydrogen studies |
| Article | |
| Title | Efficient transfer of positrons from a buffer-gas-cooled accumulator into an orthogonally oriented superconducting solenoid for antihydrogen studies |
| Author(s) |
Comeau, D (York U., Canada) ; Dror, A (York U., Canada) ; Fitzakerley, D (York U., Canada) ; George, M C (York U., Canada) ; Hessels, E A (York U., Canada) ; Storry, C H (York U., Canada) ; Weel, M (York U., Canada) ; Grzonka, D (Julich, Forschungszentrum) ; Oelert, W (Julich, Forschungszentrum) ; Gabrielse, G (Harvard U., Phys. Dept.) ; Kalra, R (Harvard U., Phys. Dept.) ; Kolthammer, W S (Harvard U., Phys. Dept.) ; McConnell, R (Harvard U., Phys. Dept.) ; Richerme, P (Harvard U., Phys. Dept.) ; Mullers, A (Mainz U., Inst. Phys.) ; Walz, J (Mainz U., Inst. Phys.) |
| Publication | 2012 |
| In: | New J. Phys. 14 (2012) 045006 |
| DOI | 10.1088/1367-2630/14/4/045006 |
| Accelerator/Facility, Experiment | CERN AD ; ATRAP AD-2 |
| Abstract | Positrons accumulated in a room-temperature buffer-gas-cooled positron accumulator are efficiently transferred into a superconducting solenoid which houses the ATRAP cryogenic Penning trap used in antihydrogen research. The positrons are guided along a 9 m long magnetic guide that connects the central field lines of the 0.15 T field in the positron accumulator to the central magnetic field lines of the superconducting solenoid. Seventy independently controllable electromagnets are required to overcome the fringing field of the large-bore superconducting solenoid. The guide includes both a 15 degrees upward bend and a 105 degrees downward bend to account for the orthogonal orientation of the positron accumulator with respect to the cryogenic Penning trap. Low-energy positrons ejected from the accumulator follow the magnetic field lines within the guide and are transferred into the superconducting solenoid with nearly 100% efficiency. A 7 m long 5 cm diameter stainless-steel tube and a 20 mm long, 1.5 mm diameter cryogenic pumping restriction ensure that the 10(-2) mbar pressure in the accumulator is isolated well from the extreme vacuum required in the Penning trap to allow for long antimatter storage times. |