• F. Gerigk, C. Carli, R. Garoby, K. Hanke, A.M. Lombardi, R. Maccaferri, S. Maury, S. Ramberger, C. Rossi, M. Vretenar
  CERN, Geneva

The civil engineering works of the Linac4 linear accelerator at CERN started in October 2008 and regular machine operation is foreseen for 2013. Linac4 will accelerate H^- ions to an energy of 160 MeV for injection into the PS Booster (PSB). It will thus replace the ageing Linac2, which presently injects at 50 MeV into the PSB, and it will also represents the first step in the injector upgrade for the LHC aiming at increasing its luminosity. This paper reports on the status of the design and construction of the main machine elements, which will be installed in the linac tunnel from the beginning of 2012 onwards, on the progress of the civil engineering and on the ongoing activities at the Linac4 test stand.

• F. Grespan, G. De Michele, F. Gerigk, S. Ramberger
  CERN, Geneva

A one meter long hot prototype of the LINAC4 DTL, built in a collaboration with INFN Legnaro, was delivered to CERN in 2008. It was then copper plated at CERN is and is presently prepared for high-power testing at the CERN test stand in SM18. In this paper we present 2D/3D simulations and the first RF low-power measurements to verify the electromagnetic properties of the cavity and to tune it before the high-power RF tests. In particular, the influence of the post couplers was studied in order to guarantee stabilization of the accelerating field during operation. We present an equivalent circuit model of the DTL, together with a comparison of 3D simulations and measurement results for the hot model.