Rainer Wanzenberg | Searcharxiv

arXiv2000

A Fast Switchyard for the TESLA FEL-Beam Using a Superconducting Transverse Mode Cavity

In the present design of the TESLA Linear Collider with integrated X-ray Laser Facility it is necessary that 1 ms long bunch trains with about 10000 bunches are generated and distributed to several free electron laser (FEL) beam lines. The different scientific applications of the X-ray FELs need specific filling patterns of the bunches in the bunch train. It is shown that a fast switch-yard based on a superconducting transverse mode cavity can be used to generate the required bunch pattern in a flexible way while keeping the beam loading in the main linear accelerator constant. The conceptual design of the beam optics and the transverse mode cavity are presented.

physics.acc-ph↗

arXiv2000

Lattice Matching with a Quadrupole Missing

The lattice for the present design of the TESLA Linear Collider with integrated X-Ray Laser Facility is basically a FODO structure with constant beta-function. There are more than 800 individually powered superconducting quadrupoles to focus the beam in the two main linear accelerators (each with a length of 15 km). For the availability of the beams it is important that a power supply failure or even a magnet failure does not cause a significant down time of the linac. It is demonstrated that the beta-function can be matched with a quadrupole "missing". One part of the main linac (up-to 50 GeV) will be used to accelerate the High Energy Physics beam and the Free Electron Laser drive beam with different accelerating gradients. Therefore the betatron phase advance will be 60 deg. or 90 deg. depending on the beam energy. It is shown that even in that case it is possible to match the lattice simultaneously for both beams with a quadrupole missing.

physics.acc-ph↗