SCU Phase Shifter Meeting 04/19/2016

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)

Heinz-Dieter’s phase shifter analysis

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

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