1. Electron Ring IP Region Optics
Fanglei Lin
MEIC R&D Meeting, JLab, February 12, 2015
F. Lin

2. New Detector Region ion e-
1.6 m
1.4 m
2.4 m
3 m
2.6 m e-
ion
Endcap
5 m
Central detector IP
Electron ring FFQs (permanent and electric quads) can be placed in the two endcaps.

3. Baseline Upstream FFQs (@ 10 GeV)
Max. x= 7 mm
*=(10,2)cm
3 m e-
0.5 m elec. 29 T/m, rinner = 2 cm, router = 9 cm
1 m ion spectrometer 
0.5 m, perm., 30 T/m, rinner = 2 cm, router = 3 cm
x= 4 mm
x= 2.4 mm
0.5 m elec. 41 T/m, rinner = 4 cm, router = 11 cm

4. New Upstream FFQs (@ 10 GeV)
2.4 m
0.5 m elec. 43 T/m, rinner = 5 cm, router = 10 cm
1 m ion spectrometer
0.5 m, perm., 28 T/m, rinner = 2 cm, router = 2.7 cm
0.5 m, perm., 35 T/m, rinner = 2 cm, router = 3 cm
Max. x = 4.2 mm
*=(10,2)cm
x= 1.9 mm
Max. y = 3 mm
0.5 m elec. 37 T/m, rinner = 3 cm, router= 6 cm

5. Baseline Downstream FFQs (@ 10 GeV)
3.2 m
0.6 m, elec., 48 T/m
0.3 m, perm., 0 T/m
*=(10,2)cm
1.5 m
Max. x= 4.9 mm
0.4 m, elec., 62 T/m
0.3 m, elec., 29 T/m
7.8 m

6. New Downstream FFQs (@ 10 GeV)
0.7 m, elec., 62 T/m, rinner = 4 cm
0.5 m, perm., 39 T/m, rinner = 2.5 or 3 cm, router = 4.8 or 7 cm ~ 8 cm separation of ion and e- beams
OR 0.5 m, elec. quad shared by two beams e- 
2.2m
1.6 m
7.8 m
*=(10,2)cm
Max. x = 3.1 mm
x = 1.2 mm
Max. y = 2.3 mm
0.7 m, elec., 41 T/m, , rinner = 8 cm
0.5 m, elec., 8 T/m, , rinner = 8 cm
Outer radii are limited by the beam separation

7. Downstream FFQs + Chicane
Baseline
New

8. Back Up

9. “Round” Beam Upstream FFQs (@ 10 GeV)
0.5 m elec. 16 T/m
1 m ion spectrometer 
0.7 m, perm., 44 T/m, rinner = 2 cm, router = 3.5 cm
0.7 m, perm., 45 T/m, rinner = 3 cm, router = 9 cm
Max. x= 4.1 mm
*=(10,2)cm
x= 2.1 mm

10. “Round” Beam Downstream FFQs (@ 10 GeV)
0.7, 0.7, 0.5 m elec. 55, 41, 7 T/m
0.5 m, perm., 19 T/m, rinner = 3 cm, router = 4 cm e- 
2.2m
1.6 m
7.8 m
*=(10,2)cm
Max. x = 3.8 mm
x = 1.2 mm

11. Baseline
Round beam
Flat beam Or