1. Ion Collider Ring Using Superferric Magnets
V. Morozov, A. Hutton, F. Lin, F. Pilat, Y. Zhang
MEIC R&D Meeting, JLab, August 21, 2014
F. Lin

2. Boundary Conditions Reusing of PEP-II hardware as much as possible
~2500 m ring circumference
Superferric magnets for the ion collider ring
Maximum field of about 2 T
Supposed to be cheap
Run at 4 K
Quickly rampable at a few T/s
Ring components included so far
Dipoles: 0.14 m edge m magnetic length m edge, 2 T maximum field
Quadrupoles: 0.05 m edge m magnetic length m edge, <=2 3 cm radius = 67 T/m
Sextupole/corrector package: 0.05 m edge m magnetic length m edge, <=2 3 cm radius = 4400 T/m2, next to each quadrupole
BPMs: 0.15 m, next to each quadrupole
Spacings
0.15 m and 0.6 m between the element physical edges in the arcs
One ion FODO cell per one electron TME-type cell
Maximum proton momentum of 79.4 GeV/c 2

3. FODO Cell Aperture radius 30 mm Dipoles Quadrupoles
Magnetic/physical length 6.5/6.78 m
Bending angle 49.1 mrad (2.8), bending radius m
GeV/c
Quadrupoles
Magnetic/physical length 0.8/0.9 m
52.4 and T/m field 79.4 GeV/c for 90 x/y betatron phase advance
1.57 and mm radius
Sextupole/corrector package next to each quadrupole
Magnetic/physical length 0.5/0.6 m
2 30 mm focusing sextupole adds 22.0/-4.7 x/y units of chromaticity
2 30 mm defocusing sextupole adds -2.5/11.6 x/y units of chromaticity
BPM next to each quadrupole
Physical length 0.15 m
Drifts
0.6 m and 0.15 m
Complete FODO
Length m
Arc radius m 3

4. Dispersion Suppressor
Quadrupoles
52.9, -52.4, 63.3, and T/m field 79.4 GeV/c
1.59, -1.57, 1.90 and mm radius 4

5. Straight FODO Quadrupoles
54.2 and T/m field 79.4 GeV/c for 90 x/y betatron phase advance
1.63 and mm radius 5

6. Matching Section Quadrupoles
52.1, -52.8, 43.8, and T/m field 79.4 GeV/c
1.56, -1.58, 1.31 and mm radius 6

7. Complete Ring Circumference: 2510.6 m 90 crossing angle of figure 8
Each arc: 270 with radius of 187 m, m long
44 FODO cells per arc + 4 FODO cells per arc used for dispersion suppression
Each straight: m long
17 FODO cells per straight + 4 FODO cells per straight used for matching
tr = 17.96 7

8. Layout 8