THZ FACILITY AT ELBE: A VERSATILE TEST FACILITY FOR ELECTRON BUNCH DIAGNOSTICS ON QUASI-CW ELECTRON BEAMS

Abstract

Superconducting radiofrequency (SRF) accelerator technology can provide relativistic electron bunches with quasi-cw repetition rates scaling from the kHz to GHz regime [1, 2, 3, 4]. The SRF accelerator ELBE [1] is up to now Europe’s only quasi-cw linear electron accelerator (LINAC) that has been operating for more than 10 years as a driver for several secondary radiation sources. In the past four years the accelerator has been upgraded to eventually also allow for electron bunch compression down to the sub ps regime. Although recent combined electro-optic and interferometric measurements show that the sub ps regime has not yet been reached, exhibiting a shortest bunch duration of 1.2 ps (FWHM). The ELBE accelerator in combination with the super-radiant THz sources represents a novel test bed for diagnostics on quasi-cw electron beams. This has been recognized by the Helmholtz-Research Association by defining the THz sources at ELBE as a test facility for diagnostics on quasicw electron beams. The development of suitable diagnostic techniques is of great importance for various energy recovery linac accelerators (ERL) coming online in the next few years [2, 4] as well as facilities like the European X-FEL [5] and FLASH [6] when operated in long bunch train mode of operation.