• O. Mete, E. Chevallay, A.E. Dabrowski, S. Döbert, K. Elsener, V. Fedosseev, T. Lefèvre, M. Petrarca
  CERN, Geneva
• D. Egger, O. Mete
  EPFL, Lausanne
• R. Roux
  LAL, Orsay

Within the framework of the second Joint Research Activity PHIN of the European CARE program, a new photo injector for CTF3 drive beam has been designed and installed by collaboration between LAL, CCLRC and CERN. The laser driven rf photo injectors are recent candidates for high-brightness, low-emittance electron sources. One of the main beam dynamics issues for a high brightness electron source is the optimization of beam envelope behavior in the presence of the space charge force in order to get low emittance. Beam based measurements have been made during the commissioning runs of the PHIN 2008 and 2009 including measurements of the emittance, using multi-slits technique. In this work the photo injector will be described and the first beam measurement results will be presented and compared with the PARMELA simulations.

• A.S. Fisher
  SLAC, Menlo Park, California
• A. Goldblatt, T. Lefèvre
  CERN, Geneva

Synchrotron-light telescopes will monitor the profiles of the two LHC proton beams. At collision energy (7 TeV), each telescope will image visible light from a superconducting dipole used to increase beam separation for the RF-cavities. At injection (0.45 TeV), this source must be supplemented by a two-period superconducting undulator 80 cm from the dipole. We will present the mechanical and optical layouts of the telescope. The initial plan to use dipole edge radiation at high beam energy, for its increased visible emission, suffers from significant diffractive blurring. We will instead collect radiation from the first 2 to 3 m of the dipole’s interior. An optical "trombone" delay line will provide the large shift in focus. We will discuss calculations and measurements of blurring by diffraction and by this extended source, and present an alternative optical design using off-axis elliptical mirrors.

• M. Olvegård, A.E. Dabrowski, S. Döbert, T. Lefèvre
  CERN, Geneva
• E. Adli
  University of Oslo, Oslo

The CTF3 provides high current (28A) high frequency (12GHz) electron beams, which are used to generate high power radiofrequency pulses at 12GHz by decelerating the electrons in resonant structures. A Test Beam Line (TBL) is currently being built in order to prove the efficiency and the reliability of the RF power production with the lowest level of particle losses. As the beam propagates along the line, its energy spread grows up to 60%. For instrumentation, this unusual characteristic implies the developments of new and innovative techniques. One of the most important tasks is to measure the beam energy spread with a fast time resolution. The detector must be able to detect the energy transient due to beam loading in the decelerating structures (nanosecond) but should also be capable to measure bunch to bunch fluctuations (12GHz). This paper presents the design of the spectrometer line detectors.

• B. Cheymol, E. Bravin, C. Dutriat, T. Lefèvre
  CERN, Geneva

Linac4 is the first step of the future LHC injectors chain. This LINAC will accelerate H^- ions from 45 keV to 160 MeV. During the commissioning phase of LINAC4, emittance measurements will be required at 45 keV, 3 MeV and 12 MeV. For this purpose a slit&grid system is currently being developed. The material and geometry of the wires and of the slits need to be optimized in order to reduce the effects of the energy deposition and maximize the signals: carbon, titanium steel and tungsten have been considered and studied. This document describes the results of the studies carried out during the design of the emittance meter and the first results during the commissioning.