First Beam Spectra of SC Third Harmonic Cavity at FLASH

Abstract

Third harmonic superconducting cavities have been designed and fabricated by FNAL to minimise the energy spread along bunches in the FLASH facility at DESY. A module, consisting of four nine-cell 3.9 GHz cavities, has been installed in FLASH. The first measurement with beam excitation is presented, and the comparisons to transmission measurement without beam and simulations are made. Higher order modes (HOMs) are able to propagate to adjacent cavities through attached beam tubes. Modes from 1.3 GHz cavities in the module nearby also propagate into this module.

Presented at XXV Linear Accelerator Conference (LINAC10), Tsukuba, Japan, Sep 12-17, 2010

Cited by in corpus (4)

• Simulations of higher order modes in the ACC39 module of FLASH
• Higher Order Modes in Coupled Cavities of the Flash Module ACC39
• Higher order mode spectra and the dependence of localized dipole modes on the transverse beam position in third harmonic superconducting cavities at FLASH
• A Study of Beam Position Diagnostics with Beam-excited Dipole Higher Order Modes using a Downconverter Test Electronics in Third Harmonic 3.9 GHz Superconducting Accelerating Cavities at FLASH