1. Optics ‘Scrapbook’ for ERL Test Facility
Alex Bogacz
November 13, 2012

2. Two passes ‘up’ + Two passes ‘down’
ERL-TF (300 MeV) - Layout
5 MeV
DE = 75 MeV
DE = 75 MeV
DC = l/2
5 MeV
Two passes ‘up’ + Two passes ‘down’
Alex Bogacz November 13, 2012

3. Two passes ‘up’ + Two passes ‘down’
ERL-TF (300 MeV) - Layout
5 MeV
DE = 75 MeV
DE = 75 MeV
DC = l/2
5 MeV
Two passes ‘up’ + Two passes ‘down’
Alex Bogacz November 13, 2012

4. Arc 1 Optics – FMC Lattice 10 2 -2
BETA_X&Y[m]
DISP_X&Y[m]
BETA_X
BETA_Y
DISP_X
DISP_Y
80 MeV
4×450 sector bends
Qx,y = 1.25
triplet: Q1 Q2 Q3
singlet: Q4
triplet: Q3 Q2 Q1
quadrupoles (10 cm long)
Q1 G[kG/cm] = -0.34
Q2 G[kG/cm] = 0.47
Q3 G[kG/cm] = -0.30
Q4 G[kG/cm] = -0.33
dipoles (40 cm long)
B = 5.01 kGauss
Alex Bogacz November 13, 2012

5. Arc 3 Optics – FMC Lattice 10 2 -2
BETA_X&Y[m]
DISP_X&Y[m]
BETA_X
BETA_Y
DISP_X
DISP_Y
230 MeV
8×22.50 sector bends
Qx,y = 1.25
triplet: Q1 Q2 Q3
singlet: Q4
triplet: Q3 Q2 Q1
quadrupoles (15 cm long)
Q1 G[kG/cm] = -0.40
Q2 G[kG/cm] = 1.37
Q3 G[kG/cm] = -1.10
Q4 G[kG/cm] = -0.43
dipoles (40 cm long)
B = 7.47 kGauss
Alex Bogacz November 13, 2012

6. Switchyard - Vertical Separation of Arcs
Arc 1 (80 MeV)
Arc 3 (230 MeV)
Alex Bogacz November 13, 2012

7. Vertical Spreaders - Optics
Spr. 1 (80 MeV)
Spr. 3 (230 MeV) 20 1 -1
BETA_X&Y[m]
DISP_X&Y[m]
BETA_X
BETA_Y
DISP_X
DISP_Y 20 1 -1
BETA_X&Y[m]
DISP_X&Y[m]
BETA_X
BETA_Y
DISP_X
DISP_Y
vertical step I
vertical step II
vertical chicane
Alex Bogacz November 13, 2012

8. Arc 1 Optics (80 MeV) – arc1.mdx 20 2 -2
BETA_X&Y[m]
DISP_X&Y[m]
BETA_X
BETA_Y
DISP_X
DISP_Y
Isochronous Arc
pathlength: 36 × lRF
2-step vert. Spreader
1800 Arc
2-step vert. Recombiner
Spr. dipoles:
300 bends (1 rec. + 3 sec.)
Lb = 30 cm
B = 5 kGauss
Arc dipoles :
4450 bends(sec.)
Lb = 40 cm
B = 5 kGauss
Rec. dipoles:
300 bends (3 sec rec.)
Lb = 30 cm
B = 5 kGauss
quads: Lq = cm G  0.6 kGauss/cm
Alex Bogacz November 13, 2012

9. Arc 2 Optics (155 MeV) – arc2.mdx 20 2 -2
BETA_X&Y[m]
DISP_X&Y[m]
BETA_X
BETA_Y
DISP_X
DISP_Y
Isochronous Arc
pathlength: 36 × lRF
2-step vert. Spreader
Magnetic field scaling (dipoles and quads)
‘Arc 2’ = ‘2’  ‘Arc 1’
1800 Arc
2-step vert. Recombiner
Spr. dipoles:
300 bends (1 rec. + 3 sec.)
Lb = 30 cm
B = 10 kGauss
Arc dipoles :
4450 bends(sec.)
Lb = 40 cm
B = 10 kGauss
Rec. dipoles:
300 bends (3 sec rec.)
Lb = 30 cm
B = 10 kGauss
quads: Lq = cm G  1.2 kGauss/cm
Alex Bogacz November 13, 2012

10. Arc 3 Optics (230 MeV) – arc3.mdx 20 2 -2
BETA_X&Y[m]
DISP_X&Y[m]
BETA_X
BETA_Y
DISP_X
DISP_Y
Isochronous Arc
pathlength: 36× lRF
Chicane vert. Spreader
Chicane vert. Recombiner
1800 Arc
Spr. dipoles:
bends ( rec.)
Lb = 30 cm
B = 5 and 10 kGauss
Arc dipoles :
822.50 bends(sec.)
Lb = 40 cm
B = 5 kGauss
Rec. dipoles:
bends ( rec.)
Lb = 30 cm
B = 5 and 10 kGauss
quads: Lq = cm G  1.2 kGauss/cm
Alex Bogacz November 13, 2012

11. Arc 4 Optics (305 MeV) – arc4.mdx 20 2 -2
BETA_X&Y[m]
DISP_X&Y[m]
BETA_X
BETA_Y
DISP_X
DISP_Y
Isochronous Arc
pathlength: 35.5 × lRF
Chicane vert. Spreader
Magnetic field scaling (dipoles and quads)
‘Arc 4’ = ‘4/3’  ‘Arc 3’
Chicane vert. Recombiner
1800 Arc
Spr. dipoles:
bends ( rec.)
Lb = 30 cm
B = 6.7 and 13.4 kGauss
Rec. dipoles:
bends ( rec.)
Lb = 30 cm
B = 6.7 and 13.4 kGauss
Arc dipoles :
822.50 bends(sec.)
Lb = 40 cm
B = 6.7 kGauss
quads: Lq = cm G  1.6 kGauss/cm
Alex Bogacz November 13, 2012

12. Linac 1 and 2 - Symmetized Optics
Arc 2
7.4 12 5
BETA_X&Y[m]
DISP_X&Y[m]
BETA_X
BETA_Y
DISP_X
DISP_Y
Arc 3
Linac 1 – linac1.mdx
155 MeV
230 MeV
inj
7.4 12 5
BETA_X&Y[m]
DISP_X&Y[m]
BETA_X
BETA_Y
DISP_X
DISP_Y
Arc 3
Arc 4
Linac 2 – linac2.mdx
230 MeV
ext
305 MeV
Alex Bogacz November 13, 2012

13. Linac 1 and 2 - Multi-pass ER Optics
Alex Bogacz November 13, 2012

14. Summary ERL-TF at CERN Multi-pass linac Optics in ER mode
‘Test bed’ for SRF cavities at high current
Multi-pass linac Optics in ER mode
Choice of linac RF MHz SRF
Linear lattice: 2-pass ‘up’ + 2-pass ‘down’
Arc Optics Choice
Synchronous acceleration → Isochronous arcs
Flexible Momentum Compaction Optics
Complete Arc Architecture
Vertical switchyard
Matching sections: Linac-Switchyard-Arc
‘First cut’ Lattice design for ERL-TF
Two Linacs + Four Arcs
Alex Bogacz November 13, 2012