1. SCU Phase Shifter Meeting
04/19/2016

2. Phase Integral Requirements
From Heinz-Dieter’s analysis the minimum phase integral required is ~ 350 T2mm3
Need to add excess strength for continuous scans
Photon energy scans are to be performed over a range of ±2.5% but not smaller than ±25 eV.
Will perform analysis to determine the excess strength that is needed
Will have to consider hysteresis in the phase shifter (may be advantageous to avoid operating near zero field)

3. Heinz-Dieter’s phase shifter analysis

4. Field Strength Estimates
Second Field Integral k 2k
First Field Integral k -k
From Heinz-Dieter’s analysis the minimum phase integral required is ~ 350 T2mm3
Assume PS length is 100 mm and pole length is 10 mm
Then k = 1900 µTm
Central pole required strength is 3800 µTm -> .38 T for a 1 cm pole
Required strength will be somewhat higher to account for excess capacity and non-ideal effects

5. Possible layouts 1: * y-direction is along undulator field orientation
ECy/PS PS
ECx 1:
* y-direction is along undulator field orientation
EC – end corrector pole
PS – phase shifter pole 2: PS
Ecx/PS
ECy 3: PS
Ecx/PS
ECy
Scenario 1
y-direction correction is closest to the undulator end
Phase shifter and end corrections are closely coupled
Higher strength might be required for ECy/PS poles
Scenario 2
y-direction correction is further from the undulator end (may lead to larger beam displacement at the ends)
Phase shifter and main undulator end corrections are decoupled (phase shifter can be controlled with one power supply + small trim coil on a separate power supply for x correction)
Scenario 3
Phase shifter and main undulator end corrections are decoupled
Higher field is needed in PS poles to compensate for the shorter drift length