Author: Mary, A.
Paper Title Page
THPC151 The 65 mm Period Electromagnetic/Permanent Magnets Helical Undulator at SOLEIL 3239
 
  • F. Marteau, P. Berteaud, F. Bouvet, L. Chapuis, M.-E. Couprie, J.P. Daguerre, T.K. El Ajjouri, J.-M. Filhol, P. Lebasque, J.L. Marlats, A. Mary, K. Tavakoli
    SOLEIL, Gif-sur-Yvette, France
  
  SOLEIL pre­pares a new 65 mm pe­ri­od Elec­tro­mag­net­ic/Per­ma­nent Mag­nets He­li­cal Un­du­la­tor (EMPHU), with a rapid switch­ing at 5 Hz of the po­lar­iza­tion re­quired for dichroïsm ex­per­i­ments. The ver­ti­cal field Bz is pro­duced by coils fed by a fast switch­ing power sup­ply (de­signed and built in house), with a max­i­mum cur­rent of 350 A and a po­lar­i­ty switch­ing time short­er than 100 ms. The coils con­sist of 25 stacked cop­per lay­ers shaped by water jet cut­ting. The cur­rent flows in 16 lay­ers and 9 of them are cooled with ther­mal drain to a water pip­ing. 4 ad­di­tion­al power sup­plies feed 2 types of cor­rec­tion coils for the dy­nam­ic com­pen­sa­tion of the field in­te­grals, be­sides the ones for the ter­mi­na­tion. 1.28 T re­ma­nence NdFeB per­ma­nent mag­nets gen­er­ate the hor­i­zon­tal field Bx. Peak Bz and Bx in the he­li­cal con­fig­u­ra­tion reach 0.24 T at 14.7 mm min­i­mum gap. Ther­mal mod­elling and mea­sure­ments aim at keep­ing the mag­net tem­per­a­ture con­stant. The stat­ic mag­net­ic con­fig­u­ra­tion was op­ti­mised using the IDBuilder soft­ware and the tra­jec­to­ry were checked for in­sur­ing a good re­pro­ducibil­i­ty of the pho­ton beam point­ing when sweep­ing from one he­lic­i­ty to the other.