Muon Acceleration for Neutrino Factory and Muon Collider

Muon Acceleration for Neutrino Factory and Muon Collider Alex Bogacz Thomas Jefferson National Accelerator Facility Operated by JSA for the U. S. Department of Energy Alex Bogacz 1

Overview Cost effective schemes for accelerating muon beams for a stagable, 5 Ge. V Neutrino Factory (Nu. MAX) SRF efficient design based on multi-pass (4. 5) Dogbone RLA Exploration of dual-use (H- and muons) linac concepts Reducing the cost while maintaining performance through exploring interplay between the cooling systems and the acceptance of the accelerator Significant groundwork (schemes and building blocks) was already laid by the IDS-NF efforts and by MASS Optimize RLA scheme for Higgs Factory and beyond (MC): Number of passes (beam loading) RLA with multi-pass arcs Thomas Jefferson National Accelerator Facility Operated by JSA for the U. S. Department of Energy Alex Bogacz Nu. Fact'15, Rio de Janeiro, Brazil, August 11, 2015 2

Nu. MAX Acceleration – Design Options Scheme I 5 Ge. V 255 Me. V/c 1. 25 Ge. V 160 m 70 m /pass Me. V 840 5 Ge. V Scheme II 255 Me. V/c 160 m m 290 e. V 5 G 3. 7 1. 25 Ge. V Thomas Jefferson National Accelerator Facility Operated by JSA for the U. S. Department of Energy Alex Bogacz Nu. Fact'15, Rio de Janeiro, Brazil, August 11, 2015 3

Initial 325 MHz Linac - Transverse Acceptance p = 255 Me. V/c 1250 Me. V BETA_X&Y[m] 5 5 beta functions Aacc = 20 MV/m 0 0 f = 325 MHz 0 BETA_X BETA_Y DISP_X DISP_Y 160 22 short cryos (2. 5 meter, 2 -cell cavity) 2. 5 s beam envelope bx, y= Size_Y[cm] Size_X[cm] 20 20 30 medium cryos (3. 5 meter 4 -cell cavity) 2. 3 m e. N = 20 mm rad bg = 2. 1 e. N = (2. 5)2 ×e. N_rms 0 0 0 a = 15 cm Ax_bet Ay_bet Ax_disp Ay_disp 160 Thomas Jefferson National Accelerator Facility Operated by JSA for the U. S. Department of Energy Alex Bogacz Nu. Fact'15, Rio de Janeiro, Brazil, August 11, 2015 4

Initial Linac – Longitudinal Profile p = 255 Me. V/c 1250 Me. V 5 5 beta functions f = 325 MHz 0 Total RF installed: 1. 513 GV 0 BETA_X&Y[m] Aacc = 20 MV/m 0 BETA_X BETA_Y DISP_X DISP_Y 160 22 short cryos (2. 5 meter, 2 -cell cavity) Cavity off crest 30 medium cryos (3. 5 meter 4 -cell cavity) Synchrotron Tune Bucket Area Energy Thomas Jefferson National Accelerator Facility Operated by JSA for the U. S. Department of Energy Alex Bogacz Nu. Fact'15, Rio de Janeiro, Brazil, August 11, 2015 5

Initial Linac – Longitudinal Acceptance p = 255 Me. V/c 1250 Me. V 5 5 beta functions f = 325 MHz 0 Total RF installed: 1. 513 GV 0 BETA_X&Y[m] Aacc = 20 MV/m 0 BETA_X BETA_Y DISP_X DISP_Y 160 22 short cryos (2. 5 meter, 2 -cell cavity) 30 medium cryos (3. 5 meter 4 -cell cavity) Initial acceptance 150 mm (blue) Longitudinal compression Longitudinal acceptance Dp/prms = 0. 112 Dzrms = 10. 3 cm e. Long= 150 mm e. Long = (2. 5)2 ×e. Long_rms Thomas Jefferson National Accelerator Facility Operated by JSA for the U. S. Department of Energy Alex Bogacz Nu. Fact'15, Rio de Janeiro, Brazil, August 11, 2015 6

325 MHz – 650 MHz Linac p = 255 Me. V/c 2. 25 Ge. V 5 5 1. 25 Ge. V A 325 MHz = 20 MV/m DISP_X&Y[m] BETA_X&Y[m] beta functions 0 0 A 650 MHz = 25 MV/m 0 BETA_X BETA_Y DISP_X DISP_Y 240 30 medium cryos (3. 5 meter) 325 MHz, 4 -cell cavity 20 long cryos (4 meter) 650 MHz, 2× 4 -cell cavity) 20 20 22 short cryos (2. 5 meter) 325 MHz, 2 -cell cavity Transverse Acceptance 0 0 e. N = 20 mm rad Size_Y[cm] Size_X[cm] 2. 5 s beam envelope 0 Ax_bet Ay_bet Ax_disp Ay_disp 240 Thomas Jefferson National Accelerator Facility Operated by JSA for the U. S. Department of Energy Alex Bogacz Nu. Fact'15, Rio de Janeiro, Brazil, August 11, 2015 7

325 MHz – 650 MHz Transition p = 255 Me. V/c 1. 25 Ge. V 5 5 2. 25 Ge. V A 325 MHz = 20 MV/m DISP_X&Y[m] BETA_X&Y[m] beta functions 0 0 A 650 MHz = 25 MV/m 0 BETA_X BETA_Y DISP_X DISP_Y 240 325 MHz linac 650 MHz linac m± time structure RF bucket Thomas Jefferson National Accelerator Facility Operated by JSA for the U. S. Department of Energy Alex Bogacz Nu. Fact'15, Rio de Janeiro, Brazil, August 11, 2015 8

Delay/Compression Chicane q q Dz q q 0 -2 DISP_X&Y[m] 2 BETA_X&Y[m]20 5 free parameters needed to match: 2 betas + 2 alphas + disp. BETA_X BETA_Y Q 0 DISP_X DISP_Y Q 2 Q 1 15. 89 Q 3 Q 4 Q 3 Q 2 Q 1 Q 0 0 -2 DISP_X&Y[m] 2 BETA_X&Y[m] 20 0 0 BETA_X BETA_Y Q’ 0 DISP_X DISP_Y Q’ 1 Q’ 2 16. 12 Q’ 3 Q’ 4 Q’ 3 Q’ 2 Q’ 1 Q’ 0 Thomas Jefferson National Accelerator Facility Operated by JSA for the U. S. Department of Energy Alex Bogacz Nu. Fact'15, Rio de Janeiro, Brazil, August 11, 2015 9

0 -2 DISP_X&Y[m] BETA_X&Y[m] 15 2 Longitudinal Compression with M 56 0 BETA_X BETA_Y DISP_X DISP_Y 173. 953 Thomas Jefferson National Accelerator Facility Operated by JSA for the U. S. Department of Energy Alex Bogacz Nu. Fact'15, Rio de Janeiro, Brazil, August 11, 2015 10

325 MHz – 650 MHz Linac p = 255 Me. V/c 2. 5 Ge. V 15 2 1. 25 Ge. V 0 -2 DISP_X&Y[m] BETA_X&Y[m] beta functions 0 BETA_X BETA_Y DISP_X DISP_Y 30 medium cryos (3. 5 meter) 325 MHz, 4 -cell cavity chicane 28 long cryos (4 meter) 650 MHz, 2× 4 -cell cavity 20 20 22 short cryos (2. 5 meter) 325 MHz, 2 -cell cavity 283 Size_Y[cm] Size_X[cm] 2. 5 s beam envelope 0 0 e. N = 20 mm rad 0 Ax_bet Ay_bet Ax_disp Ay_disp 283 Thomas Jefferson National Accelerator Facility Operated by JSA for the U. S. Department of Energy Alex Bogacz Nu. Fact'15, Rio de Janeiro, Brazil, August 11, 2015 11

650 MHz FODO Linac 2. 5 Ge. V 15 5 3. 8 Ge. V 0 0 DISP_X&Y[m] BETA_X&Y[m] beta functions 280 BETA_X BETA_Y DISP_X DISP_Y 449. 656 11 FODO cells (6 m) 4× 4 -cell cavity BETA_X BETA_Y DISP_X 4 0 5 DISP_X&Y[m] 0 BETA_X&Y[m] 15 0 5 DISP_X&Y[m] 0 0 0 BETA_X&Y[m] 15 25 FODO cells (4 m) 2× 4 -cell cavity BETA_X BETA_Y DISP_X 6 Thomas Jefferson National Accelerator Facility Operated by JSA for the U. S. Department of Energy Alex Bogacz Nu. Fact'15, Rio de Janeiro, Brazil, August 11, 2015 12

650 MHz FODO Linac 2. 5 Ge. V 15 5 3. 8 Ge. V 0 0 DISP_X&Y[m] BETA_X&Y[m] beta functions 280 BETA_X BETA_Y DISP_X DISP_Y 449. 656 25 FODO cells (4 m) 11 FODO cells (6 m) 15 15 2. 5 s beam envelope 0 0 Size_X[cm] Size_Y[cm] e. N = 20 mm rad 280 Ax_bet Ay_bet Ax_disp Ay_disp 449. 656 Thomas Jefferson National Accelerator Facility Operated by JSA for the U. S. Department of Energy Alex Bogacz Nu. Fact'15, Rio de Janeiro, Brazil, August 11, 2015 13

325 MHz – 650 MHz Linac p = 255 Me. V/c 2. 5 Ge. V 3. 8 Ge. V 5 Ge. V 25 FODO cells (4 m) 2× 4 -cell cavity 11 FODO cells (6 m) 4× 4 -cell cavity 0 -2 BETA_X&Y[m] beta functions DISP_X&Y[m] 15 2 1. 25 Ge. V 0 BETA_X BETA_Y DISP_X 325 MHz muon linac DISP_Y 449. 656 chicane 650 MHz dual-use linac Size_X[cm] Size_Y[cm] 20 20 2. 5 s beam envelope 0 0 e. N = 20 mm rad 0 Ax_bet Ay_bet Ax_disp 325 MHz muon linac Ay_disp 449. 656 chicane 650 MHz dual-use linac Thomas Jefferson National Accelerator Facility Operated by JSA for the U. S. Department of Energy Alex Bogacz Nu. Fact'15, Rio de Janeiro, Brazil, August 11, 2015 14

Dual-use Linac – muons vs protons 5 Ge. V 30 5 1. 25 Ge. V 0 0 DISP_X&Y[m] BETA_X&Y[m] muons 0 BETA_X BETA_Y DISP_X DISP_Y 275. 703 chicane 3 Ge. V 30 5 6. 8 Ge. V 0 0 DISP_X&Y[m] BETA_X&Y[m] H- 0 BETA_X BETA_Y DISP_X DISP_Y 275. 703 Thomas Jefferson National Accelerator Facility Operated by JSA for the U. S. Department of Energy Alex Bogacz Nu. Fact'15, Rio de Janeiro, Brazil, August 11, 2015 15

Linac and RLA to 5 Ge. V 255 Me. V/c 160 m 1. 25 Ge. V 70 m 840 Me. V/pass 5 Ge. V Thomas Jefferson National Accelerator Facility Operated by JSA for the U. S. Department of Energy Alex Bogacz Nu. Fact'15, Rio de Janeiro, Brazil, August 11, 2015 16

20 1 Double Arc Chicane - Optics FODO lattice: 900/900 (h/v) betatron phase adv. per cell 0 -1 DISP_X&Y[m] BETA_X&Y[m] Double achromat Optics 0 BETA_X V BETA_Y -V H DISP_X DISP_Y H H 30. 5 H -V V Thomas Jefferson National Accelerator Facility Operated by JSA for the U. S. Department of Energy Alex Bogacz Nu. Fact'15, Rio de Janeiro, Brazil, August 11, 2015 17

Arc 1 and Arc 3 top view 1. 625 Ge. V side view 3. 325 Ge. V 1. 625 Ge. V 1 m 3. 325 Ge. V Thomas Jefferson National Accelerator Facility Operated by JSA for the U. S. Department of Energy Alex Bogacz Nu. Fact'15, Rio de Janeiro, Brazil, August 11, 2015 18

6 m cells 1. 625 Ge. V 1 m dipoles 0 0 BETA_X BETA_Y DISP_X DISP_Y 2 vertical steps 113. 595 3 2 vertical steps Arc 3 8 m cells 3. 325 Ge. V 2 m dipoles 0 -3 DISP_X&Y[m] BETA_X&Y[m] 20 DISP_X&Y[m] Arc 1 -3 BETA_X&Y[m] 20 3 Arc 1 and 3 – Optics 0 BETA_X BETA_Y DISP_X DISP_Y 143. 611 Thomas Jefferson National Accelerator Facility Operated by JSA for the U. S. Department of Energy Alex Bogacz Nu. Fact'15, Rio de Janeiro, Brazil, August 11, 2015 19

Switchyard - Arc 1 and 3 1. 625 Ge. V 3. 325 Ge. V 1. 625 Ge. V Thomas Jefferson National Accelerator Facility Operated by JSA for the U. S. Department of Energy Alex Bogacz Nu. Fact'15, Rio de Janeiro, Brazil, August 11, 2015 20

Bi-sected Linac Optics 5 15 ‘half pass’ , 1250 -1625 Me. V 4 meter 90 deg. FODO cells 25 MV/m, 650 MHz, 2× 4 -cell cavity 0 0 DISP_X&Y[m] BETA_X&Y[m] quad gradient initial phase adv/cell 90 deg. scaling quads with energy 0 BETA_X BETA_Y DISP_X DISP_Y 35 1 -pass, 1625 -2475 Me. V 5 15 mirror symmetric quads in the linac 0 0 0 DISP_X&Y[m] BETA_X&Y[m] quad gradient BETA_X BETA_Y DISP_X DISP_Y 70 Thomas Jefferson National Accelerator Facility Operated by JSA for the U. S. Department of Energy Alex Bogacz Nu. Fact'15, Rio de Janeiro, Brazil, August 11, 2015 21

Multi-pass Linac Optics Arc 2 Arc 3 bx, y → bx, y axy → - axy bx = 6. 3 m by = 7. 9 m ax =-1. 2 ay =1. 3 bx, y → bx, y axy → - axy DISP_X&Y[m] 30 bx = 3. 2 m by = 6. 0 m ax =-1. 1 ay =1. 5 bx = 7. 9 m by = 8. 7 m ax =-0. 8 ay =1. 3 bx = 13. 0 m by = 14. 4 m ax =-1. 2 ay =1. 5 0 1. 25 Ge. V 0 0 BETA_X&Y[m] Arc 4 5 Arc 1 BETA_X BETA_Y 1. 625 Ge. V DISP_X DISP_Y 2. 475 Ge. V 315 3. 325 Ge. V 4. 175 Ge. V 5. 025 Ge. V Thomas Jefferson National Accelerator Facility Operated by JSA for the U. S. Department of Energy Alex Bogacz Nu. Fact'15, Rio de Janeiro, Brazil, August 11, 2015 22

A Potential Muon Accelerator Complex at Fermilab: Nu. MAX Higgs Factory 0. 8 Ge. V Proton Linac (PIPII) Accum Bunchulator er & Front Combin er End Target Initia Cool l 6 D Fin Cool C al ool LBNF Superbeam To SURF Nu. MAX: ns to SURF 0. 8 -3 Ge. V Proton Linac (PIPIII) A RL 1 Ge. V Muon Linac (325 MHz) to 63 V Ge 3 -6. 75 Ge. V Proton & 1. 25 -5 Ge. V/c Muon dual use Linac (650 MHz) To Near Detector(s) for Short Baseline Studies 300 m Higgs Factory Muon Collider ft. ft ftft. Thomas Jefferson National Accelerator Facility 23 Bogacz Concept developed by MAP Alex as part of its Muon Accelerator Staging Study (MASS) Operated by JSA for the U. S. Department of Energy 23

Beam Loading J. S. Berg J. -P. Delahaye stored energy in a cavity: fractional reduction in the cavity voltage : RF gradient G defined as: fractional voltage reduction: Thomas Jefferson National Accelerator Facility Operated by JSA for the U. S. Department of Energy Alex Bogacz Nu. Fact'15, Rio de Janeiro, Brazil, August 11, 2015 24

5 -pass RLA 5 -63 Ge. V 51. 4 Ge. V 28. 2 Ge. V 829 m 11. 6 Ge. V/pass 16. 6 Ge. V 63 Ge. V 39. 8 Ge. V Thomas Jefferson National Accelerator Facility Operated by JSA for the U. S. Department of Energy Alex Bogacz Nu. Fact'15, Rio de Janeiro, Brazil, August 11, 2015 25

Arc 1 and Arc 3 top view 16. 6 Ge. V side view 39. 8 Ge. V 16. 6 Ge. V 1 m 39. 8 Ge. V Thomas Jefferson National Accelerator Facility Operated by JSA for the U. S. Department of Energy Alex Bogacz Nu. Fact'15, Rio de Janeiro, Brazil, August 11, 2015 26

Linac – Bisected Optics E = 5 -16. 6 Ge. V 90 cells (quad gradients scaled with momentum) 0 BETA_X BETA_Y DISP_X RF DISP_Y 4. 61 f[MHz] 650 cells/cavity 5 0 0 0 BETA_X&Y[m] 5 10 490 FODO PHASE_X&Y 90 deg. 90 cells (quads reversed in mirror-symmetric pattern ) 0 Q_X Grad [MV/m] 25 Q_Y 4. 61 phase [deg] 22 Thomas Jefferson National Accelerator Facility Operated by JSA for the U. S. Department of Energy Alex Bogacz Nu. Fact'15, Rio de Janeiro, Brazil, August 11, 2015 27

Multi-pass Linac – Bisected Optics E = 5 -63 Ge. V Arc 2 Arc 1 Linac pass-2 RF f[MHz] 650 cells/cavity 5 Linac pass-3 Grad [MV/m] 25 phase [deg] 22 Thomas Jefferson National Accelerator Facility Operated by JSA for the U. S. Department of Energy Alex Bogacz Nu. Fact'15, Rio de Janeiro, Brazil, August 11, 2015 28

Arc Optics – Longitudinal Distortion 0. 3 15 E = 24 Ge. V 0 -0. 3 DISP_X&Y[m] BETA_X&Y[m] M 56 = -66. 7 cm 0 BETA_X BETA_Y 2 half cells 15 cells out DISP_X DISP_Y 100 303 BETA_X BETA_Y 2 empty cells 83 cells in 2 empty cells DISP_X DISP_Y 15 cells out 402. 975 2 half cells Quads q. F q. D DISP_X&Y[m] BETA_X&Y[m] 0. 3 15 900 FODO 0 -0. 3 Dipoles 0 BETA_X BETA_Y DISP_X L[cm] 80 80 L[cm] 50. 00 G[k. G/cm] 10. 2924 -10. 2788 B[k. G] 49. 3116 bend angle [deg] 1. 7647 3. 34 Thomas Jefferson National Accelerator Facility Operated by JSA for the U. S. Department of Energy Alex Bogacz Nu. Fact'15, Rio de Janeiro, Brazil, August 11, 2015 29

Multi-pass Arc Muon RLA 5 Ge. V (m±) 11. 6 Ge. V/pass 63 Ge. V Thomas Jefferson National Accelerator Facility Operated by JSA for the U. S. Department of Energy Alex Bogacz Nu. Fact'15, Rio de Janeiro, Brazil, August 11, 2015 30

Single- vs Multi-pass Droplet Arcs top view 16. 6 Ge. V 39. 8 Ge. V JEMMRLA - Jlab Electron Model of Muon RLA side view 16. 6 Ge. V 1 m 39. 8 Ge. V Thomas Jefferson National Accelerator Facility Operated by JSA for the U. S. Department of Energy Alex Bogacz Nu. Fact'15, Rio de Janeiro, Brazil, August 11, 2015 31

Te. V scale MC – Rapid Cycling Synchrotron J. S. Berg Thomas Jefferson National Accelerator Facility Operated by JSA for the U. S. Department of Energy Alex Bogacz Nu. Fact'15, Rio de Janeiro, Brazil, August 11, 2015 32

Rapid Cycling Synchrotrons J. S. Berg Thomas Jefferson National Accelerator Facility Operated by JSA for the U. S. Department of Energy Alex Bogacz Nu. Fact'15, Rio de Janeiro, Brazil, August 11, 2015 33

Pulsed Magnets Thomas Jefferson National Accelerator Facility Operated by JSA for the U. S. Department of Energy Alex Bogacz Nu. Fact'15, Rio de Janeiro, Brazil, August 11, 2015 34

Summary Conceptual schemes for 5 Ge. V Neutrino Factory (a la Nu. MAX) Scheme I - SRF efficient design based on multi-pass Dogbone RLA Linac (255 Me. V - 1. 25 Ge. V) Longitudinal compression Delay/Compression Chicane - Transition from 325 to 650 MHz SRF RLA (1. 25 - 5 Ge. V ) 4 droplet Arcs and multi-pass linac Scheme II – Conceptual design based on dual-use (H- and muons) linac. Further compatibility studies on: H- dynamics in a strongly focusing solenoid based FOFO channel, e. g. effect of solenoid fringe fields on H- ion stripping Optimized RLA scheme for Higgs Factory and beyond (MC): Number of passes limited by beam loading RLA with multi-pass arcs Te. V scale acceleration - Rapid Cycling Synchrotrons Thomas Jefferson National Accelerator Facility Operated by JSA for the U. S. Department of Energy Alex Bogacz Nu. Fact'15, Rio de Janeiro, Brazil, August 11, 2015 35