• 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.

• L. Cultrera, F. A. Anelli, M. Bellaveglia, G. Di Pirro, D. Filippetto, E. Pace, C. Vicario
  INFN/LNF, Frascati (Roma)

The experimental setup implemented in the SPARC linac control system used to monitor the laser beam energy and to measure the beam charge by means of a Faraday Cup will be illustrated and discussed. The experimental setup makes use of National Instruments 2 GS/s 8-Bit digitizer board. This tool has been shown to be useful in order to monitor the laser beam energy stability and to evaluate the quantum efficiency of the cathode.

• E. Guetlich, P. Forck, B. Walasek-Höhne
  GSI, Darmstadt
• W. Ensinger
  Technical University Darmstadt, Darmstadt

Optical properties of scintillating screens were studied for various materials and different ion beams at GSI. C²⁺, Ar¹⁰⁺, Ni⁹⁺ and U²⁸⁺-ion beams were applied, in the energy range from 5.5 to 11.4 MeV/u with currents up to some mA, as delivered by the heavy ion LINAC at GSI. Scintillation screens are widely used and are an essential part of a pepper-pot emittance device for which the precise mapping of the beam profile is a critical issue. However, precise measurements of the beam profile yield ambivalent results, especially for high beam currents*,**. The investigations were not only focused on well-known scintillators but also ceramic materials with lower light yield were studied. Their properties (light yield, beam width and higher statistical moments) are compared with different Quartz-glass screens. The recorded beam width shows dependence on the scintillation material and a decrease of the light yield was observed for some materials. Additionally, the light yield and beam width depend significantly on the screen temperature, which is increased by the ion impact. The empirical results are discussed and concepts for further investigations on the materials are presented.

* E. Gütlich, P. Forck et al., GSI-Scientific Report 2007 p.105 and 2008 (to be published).
** E. Gütlich, P. Forck, et al., Proc. Beam Instrum. Workshop BIW, Lake Tahoe (2008).

• E. Chiadroni, D. Alesini, M. Bellaveglia, M. Castellano, L. Cultrera, G. Di Pirro, M. Ferrario, L. Ficcadenti, D. Filippetto, G. Gatti, E. Pace, C. Vaccarezza, C. Vicario
  INFN/LNF, Frascati (Roma)
• A. Cianchi
  Università di Roma II Tor Vergata, Roma
• B. Marchetti
  INFN-Roma II, Roma
• A. Mostacci
  Rome University La Sapienza, Roma
• C. Ronsivalle
  ENEA C.R. Frascati, Frascati (Roma)

The characterization of the transverse phase space of electron beams with charge density and high energy is a fundamental requirement for particle accelerator facilities. The knowledge of characteristics of the accelerated electron beam is of great importance for the successful developement of the SPARC FEL. Here the high-energy emittance measurement with the quadrupole scan technique using two quadrupoles arranged as a doublet is discussed.