Author: Brunner, O.
Paper Title Page
TUPME040 TLEP: High-performance Circular e+e Collider to Study the Higgs Boson 1658
  • M. Koratzinos, O. Brunner, A.C. Butterworth, J.R. Ellis, P. Janot, E. Jensen, J.A. Osborne, F. Zimmermann
    CERN, Geneva, Switzerland
  • R. Aleksan
    CEA/DSM/IRFU, France
  • A.P. Blondel
    DPNC, Genève, Switzerland
  • M. Zanetti
    MIT, Cambridge, Massachusetts, USA
  The recent discovery of a light Higgs boson has opened up considerable interest in circular e+e Higgs factories around the world. We report on the progress of the “TLEP3” concept since last year. Two options are considered: LEP3, a 240 GeV centre-of-mass (Ecm) e+e machine in the LHC tunnel with cost only a fraction of the cost of an equivalent linear collider, due to the use of existing infrastructure and the two general-purpose LHC detectors, and TLEP, an e+e machine in a new 80 km tunnel that can operate up to an Ecm of 350 GeV. Both concepts enjoy the extensive know-how on circular colliders and how to deliver their design luminosity, and the existence of up to four interaction points. The attainable luminosities are 1034/cm2/s and 5x1034/cm2/s per interaction point for LEP3 and TLEP respectively. Both machines can operate as Tera-Z and Mega-W boson factories, giving decisive opportunities for over-constraining the electroweak sector of the Standard Model. The technical challenges and possible ways to improve the performance further will be discussed.  
THPWO082 Commissioning of the Linac4 RFQ at the 3 MeV Test Stand 3951
  • C. Rossi, L. Arnaudon, G. Bellodi, J.C. Broere, O. Brunner, A.M. Lombardi, J. Marques Balula, P. Martinez Yanez, J. Noirjean, C. Pasquino, U. Raich, F. Roncarolo, M. Vretenar
    CERN, Geneva, Switzerland
  • M. Desmons, A. France, O. Piquet
    CEA/IRFU, Gif-sur-Yvette, France
  Linac4, the future 160MeV H injector to the CERN Proton Synchrotron Booster, is presently under construction at CERN as a first step of the planned upgrade of the LHC injectors. The low energy section of LINAC4, consisting of an ion source, a 352.2 MHz Radio Frequency Quadrupole (RFQ) and a chopper line is being commissioned in a dedicated test stand before installation in its final position in the tunnel. The RFQ is designed to accelerate a 45 keV, 70 mA, H beam to 3 MeV, with an efficiency of 95% while preserving the transverse emittance. The RFQ, a four-vane structure 3 m in length, has been designed in collaboration with CEA/IRFU and it has been built at the CERN workshop. The precise fabrication has allowed to achieve a field flatness of 1%. The completion of the accelerating structure in September 2012 was followed by a complete series of bead-pull measurements and by high-power conditioning to the nominal power of 0.39 MW corresponding to a voltage of 78 kV across the 3 meters. Measurements with beam are foreseen during the first half of 2013. This paper reports the results of the low-power and high power RF commissioning as well as the status of beam measurements.