1. Compensation of Detector Solenoid Coherent Orbit Correction
G.H. Wei, V.S. Morozov, Fanglei Lin
JLEIC Collaboration Meeting Spring, 2016
F. Lin

2. Contents
Scenarios of coherent orbit correction

3. JLEIC and Detector Solenoids
Length
4 m
Strength
< 3 T
Crossing Angle
50 mrad

4. JLEIC coherent orbit correction
A solution: Solenoid + Quads(normal+skew) + Anti-Solenoid
Quads(normal+skew)
e-ring
Ion ring IP
: Orbit corrector 4

5. Scenarios of coherent orbit correction
A solution: Solenoid + Quads(normal+skew) + Anti-Solenoid
Quads(normal+skew)
3 Correctors
4 correctors
phase scenario: -pi, -pi/2, pi/2, pi
Modified phase scenario IP
: Orbit corrector 5

6. Scenarios of coherent orbit correction
3 Correctors
Pro: Local control of coherent orbit
Cons: 1. dy is not 0 at IP. Considering dy of 0.3 mrad, & rms bunch length of 2 cm, an offset is 6 µm for the head & tail Strength of the 2nd corrector is 2.0 mrad. Considering 0.2 m length and rigidity of 200 T.m, strength is 2 T.

7. Scenarios of coherent orbit correction
4 Correctors
Pro: Local control of coherent orbit; Small effect on dispersion
Cons: Strength of the 3rd corrector is 1.6 mrad. Considering 0.2 m length and rigidity of 200 T.m, strength is 1.6 T.

8. Scenarios of coherent orbit correction
4 Correctors
Pro: Local control of coherent orbit; Small effect on dispersion
Cons: Strength of the 3rd corrector is 1.6 mrad. Considering 0.2 m length and rigidity of 200 T.m, strength is 1.6 T.

9. Scenarios of coherent orbit correction
phase scenario: -pi, -pi/2, pi/2, pi
Pro: Kick angle of downstream corrector is < 0.1 mrad
Cons: Effect on dispersion; Strength of upstream correctors are 3.5 mrad. Considering 0.2 m length and rigidity of 200 T.m, strength is 3.5 T.

10. Scenarios of coherent orbit correction
phase scenario: -pi, -pi/2, pi/2, pi
Pro: Local control of coherent orbit; Small effect on dispersion
Cons: Effect on dispersion; Strength of upstream correctors are 3.5 mrad. Considering 0.2 m length and rigidity of 200 T.m, strength is 3.5 T.

11. Scenarios of coherent orbit correction
Modified phase scenario
Pro: Kick angle of downstream corrector is < 0.1 mrad; Kick angle of the upstream correctors are 0.26 mrad. Considering 0.2 m length and rigidity of 200 T.m, strength is 0.26 T.
Cons: Effect on dispersion;

12. Scenarios of coherent orbit correction
Modified phase scenario
Pro: Kick angle of downstream corrector is < 0.1 mrad; Kick angle of the upstream correctors are 0.26 mrad. Considering 0.2 m length and rigidity of 200 T.m, strength is 0.26 T.
Cons: Effect on dispersion;

13. Summary Scenarios No offset on FFQ dy=0 Max_Kick mrad
Effect on dispersion
3 correctors Y N 2 -
4 correctors
1.6
< 0.05 m
phase
3.5
< 0.4 m
Mod_phase
0.26

14. Thank you
F. Lin