SCU Phase Shifter Meeting 04192016 Phase Integral Requirements

SCU Phase Shifter Meeting 04/19/2016

Phase Integral Requirements • From Heinz-Dieter’s analysis the minimum phase integral required is ~ 350 T 2 mm 3 • 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 e. V. – 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 First Field Integral k 2 k k k -k • From Heinz-Dieter’s analysis the minimum phase integral required is ~ 350 T 2 mm 3 • 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 ECy/PS ECx PS ECy/PS * y-direction is along undulator field orientation 1: PS ECy Ecx/PS ECy PS Ecx/PS PS ECy 2: EC – end corrector pole PS – phase shifter pole 3: • 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 – y-direction correction is closest to the undulator end – Phase shifter and main undulator end corrections are decoupled – Higher field is needed in PS poles to compensate for the shorter drift length