Презентация на тему: Two Devices for HINS Robyn Madrak Accelerator Physics Center (APC)
Two Devices for HINS* Robyn Madrak Accelerator Physics Center (APC)
60 MeV Linac under construction at Fermilab’s meson building R&D Linac which will demonstrate novel technologies used for the first time Technical feasibility proof of (front end) for 8 GeV Linac, Project X, etc.
Solenoidal focusing cleaner, axisymmetric beam Use of SC spoke resonators Fast ferrite phase shifters will allow multiple cavities (and RFQ) to be driven by a single 2.5 MW, 325 MHz klystron => cost savings Fast Beam Chopper
Parameters
FNAL HINS
Should the HINS be extended to an 8 GeV Linac, output beam would be transferred to Fermilab’s Main Injector, with 53 MHz RF frequency HINS Linac Bunches are spaced by 325 MHz (3.1ns) In MI, RF frequency is ~53 MHz (~19ns) Don’t want bunches in the 53 MHz separatrix Chop out ~1 of every 6 bunches Additional complication: 325 ≠ n G 53 Sometimes chop 1, sometimes 2
beam is deflected by traveling pulse (electric field) b(beam)=0.073 => must slow down pulseUse traveling wave “meander” structure: 50 cm long 16 mm between chopper plates 2.4 kV per plate deflection of 6mm at end of plates
Chopper in MEBT
length of chopper plates: 50 cmdrift space downstream: 30 cmplate separation: 16 mm
We needWe needTwo pulsers to drive the ~50 Ω meanders: +/- 2.4 kVMax ~5.5 ns pulse width (including rise and fall time)53 MHz rep rateburst of 3ms @2.5Hz, or 1ms@10HzProgrammable pulse width (may sometimes chop 1 bunch, sometimes two)→ Specs do not lead to an “obvious” solution
Operates in full reflection mode (end is shorted)Operates in full reflection mode (end is shorted)Use solenoid along with shifters: phase of reflected wave determined by of ferrite ( depends upon applied H Field)Ferrite is Al doped Yttrium Iron Garnet (YIG) – TCI Ceramics AL-400Required rate: 1º/sPower Rating: ~50kW (Room Temp Cavities) or ~500kW (RFQ)
