Maksim V. Kuzin
ILC Undulator-Based Positron Source with Quarter Wave Transformer at 250 GeV CM Energy
The capture efficiency of positron source using a Quarter Wave Transformer (QWT) for focusing positrons after Ti6Al4V target with 7 mm thickness were estimated for the International Linear Collider (ILC) at center-of-mass energy of 250 GeV. QWT consists from two solenoids: first one has a length of 12 cm and about 1 T field, second one has 0.5 T field superimposed on the electric field of capture accelerator. The impact of field strength of the first solenoid on positron yield has been calculated. The peak energy deposition by beam in the first solenoid with smallest aperture radius of 11 mm was estimated.