Status of the Muon Linac and RLAs Ajit

Status of the Muon Linac and RLAs Ajit Kurup EUROnu Annual Meeting 18 th – 21 st January 2011

Status of the Muon Linac and RLAs Introduction • Status of muon linac and RLAs as presented in IDR. • Work of a number of people: – Morteza Aslaninejad, Kevin Beard, Alex Bogacz, Cristian Bonţoiu, Vasilyi Mozorov, Jürgen Pozimski, Yves Roblin • Linac design and simulations. • RLA design and simulations. • Task list. • Summary. Ajit Kurup EUROnu Annual Meeting 18 th – 21 st January 2011 Page 2

Status of the Muon Linac and RLAs Muon Acceleration in the Neutrino Factory 244 Me. V LINAC 146 m RLA I 0. 9 Ge. V The linac consists of SC RF cavities and iron shielded SC solenoids grouped into three types of cryo-modules. 79 m 0. 6 Ge. V/pass 3. 6 Ge. V 264 m RLA II 2 Ge. V/pass Chicanes have a vertical dipole spreader, horizontal bending magnets, quadrupoles for transverse focussing and a vertical dipole combiner. Ajit Kurup 12. 6 Ge. V The RLAs consist of single SC RF cavity cells and FODO quadrupole focussing throughout. EUROnu Annual Meeting 18 th – 21 st January 2011 Page 3

Status of the Muon Linac and RLAs Muon Linear Accelerator Medium Cryomodule for the middle linac Short Cryomodule for the upper linac Linac design parameters • • Input Energy 0. 244 Ge. V Transverse Acceptance normalised (2. 52*e. N) 30 mm rad Output Energy 0. 9 Ge. V Initial lattice design from Study IIa 3 -stage approach, confinement, adiabatic acceleration, boost 3 types of cryomodules Long Cryomodule for the lower linac Ajit Kurup EUROnu Annual Meeting 18 th – 21 st January 2011 Page 4

Status of the Muon Linac and RLAs Muon Linear Acccelerator • • • B field and -function using field maps from Poisson magnet simulation. Matching between sections. No cavities. Linac Section Upper Middle Lower No. of Cryomodules 6 8 11 Cell length [m] 3 5 8 RF cavities per cryomodule 1 2 4 RF gradient [MV/m] 15 17 17 max. B field [T] 1. 1 0. 874 0. 648 max. -function [m] 2. 90 4. 93 8. 25 Ajit Kurup EUROnu Annual Meeting 18 th – 21 st January 2011 Page 5

Status of the Muon Linac and RLAs SC Solenoid Simulations • • • Initial design done with Poisson. Roxie (CERN code used for LHC) now used. Shielding sufficient to prevent field leakage. Peak field is 2 T. Coils are far from quench level (can make thinner). Ajit Kurup EUROnu Annual Meeting 18 th – 21 st January 2011 Page 6

Status of the Muon Linac and RLAs Cavity Simulations • • Target energy gain of 10 Me. V per cell. Length corresponds to relativistic =1. Simulations done with Superfish, CST-MWS and COMSOL. Peak fields scaled to 33. 95 MV/m for upper linac and 38. 45 MV/m for the middle and lower linacs to achieve the design specifications of 15, 17 and 17 MV/m, respectively. Ajit Kurup EUROnu Annual Meeting 18 th – 21 st January 2011 Page 7

Status of the Muon Linac and RLAs Particle Tracking • • Gaussian beam tracking. Acceptances after 36 upper linac cells with no RF. Ajit Kurup EUROnu Annual Meeting 18 th – 21 st January 2011 Page 8

Status of the Muon Linac and RLAs Particle Tracking • • Gaussian beam tracking with RF using GPT. Gaussian beam tracking with RF using G 4 beamline. Ajit Kurup EUROnu Annual Meeting 18 th – 21 st January 2011 Page 9

Status of the Muon Linac and RLAs Chicanes • $Lc = 60 cm $ang. H = 9 deg. $BH = 10. 2 k. Gauss $Lc = 60 cm $ang. V = 5 deg. $BV = 4. 7 k. Gauss m+ m+ m- 50 cm 2. 1 Ge. V Tracking with field maps. 0. 9 Ge. V m+ m- 1. 5 Ge. V 30 1 m- FODO lattice: 900/1200 (h/v) betatron phase adv. per cell -1 DISP_X&Y[m] BETA_X&Y[m] Double achromat Optics 0 1. 7 m Combined dipole+sextupole and quadrupole magnets for the chicanes and RLAs to be simulated. 0 BETA_X H -H BETA_Y V DISP_X DISP_Y 3 cells 30 -V -H H 4 cells Ajit Kurup EUROnu Annual Meeting 18 th – 21 st January 2011 Page 10

Status of the Muon Linac and RLAs Recirculating Linear Accelerators • • Two stage RLA Both utilise 4. 5 passes. Magnet design and tracking with more realistic fields to be done. Switchyard design. 244 Me. V 146 m 0. 9 Ge. V 79 m 0. 6 Ge. V/pass 3. 6 Ge. V 264 m 2 Ge. V/pass Ajit Kurup EUROnu Annual Meeting 18 th – 21 st January 2011 12. 6 Ge. V Page 11

Status of the Muon Linac and RLAs 3 15 Mirror-symmetric Droplet Arc (bout = bin and aout = -ain , matched to the linacs) 0 -3 DISP_X&Y[m] BETA_X&Y[m] E =1. 2 Ge. V 0 BETA_X 2 cells BETA_Y DISP_X DISP_Y 130 transition 10 cells 2 cells footprint 5000 4000 3000 2000 1000 x [cm] 0 0 2000 4000 6000 8000 10000 -1000 -2000 -3000 -4000 -5000 z [cm] Ajit Kurup EUROnu Annual Meeting 18 th – 21 st January 2011 Page 12

Status of the Muon Linac and RLAs FFAG Arcs Dx • Alternative to baseline. • One arc instead of two. – Cheaper and simple closing of geometry when using = similar cells 41. 3 m removes need for complicated switchyard. 300 • Shorter beamline. • Linear Px 2 and non-linear Px 1 magnets under investigation. 60 Ajit Kurup C = 302. 4 m EUROnu Annual Meeting 18 th – 21 st January 2011 Page 13

Status of the Muon Linac and RLAs Task List • Tasks done – SC solenoid design using Poisson and ROXIE – Single-cell and double-cell SC cavity design done using Superfish and COMSOL – Particle tracking done using GPT, confirmed using Optim and G 4 beamline. • Tasks to do – – – – – • Optimise linac RF phases. Input matching into linac. Design chicane and RLA combined function quadrupoles. Model cavity with coupler ports. Field-map tracking of chicane to RLA-1 (obtain -functions and beam loss). RLA switchyard design. End-to-end tracking with field-maps and realistic input beam. Conceptual design of RF power distribution system. Beam diagnostic devices. Things that would be nice – Mechanical design of the cryomodule – Vacuum and cryogenic systems requirements (need engineering support). Ajit Kurup EUROnu Annual Meeting 18 th – 21 st January 2011 Page 14

Status of the Muon Linac and RLAs Summary A lot of work has been done … but there’s still much to do! Ajit Kurup EUROnu Annual Meeting 18 th – 21 st January 2011 Page 15