Author: Efthymiopoulos, I.
Paper Title Page
MOPEA058 CNGS, CERN Neutrinos to Gran Sasso, Five Years of Running a 500 Kilowatt Neutrino Beam Facility at CERN 211
 
  • E. Gschwendtner, K. Cornelis, I. Efthymiopoulos, A. Pardons, H. Vincke, J. Wenninger
    CERN, Geneva, Switzerland
  • I. Krätschmer
    HEPHY, Wien, Austria
 
  The CNGS facility (CERN Neutrinos to Gran Sasso) aims at directly detecting muon to tau neutrino oscillations where an intense muon-neutrino beam (1017 muon-neutrinos/day) is generated at CERN and directed over 732km towards the Gran Sasso National Laboratory, LNGS, in Italy, where two large and complex detectors, OPERA and ICARUS, are located. The CNGS facility (CNGS Neutrinos to Gran Sasso) started with the physics program in 2008 and delivered until the end of the physics run 2012 more than 80% of the approved protons on target (22.5·1019 pot). An overview of the performance and experience gained in operating this 500kW neutrino beam facility is described. Major events since the commissioning of the facility in 2006 are summarized. Highlights on the CNGS beam performance are given.  
 
MOPFI050 Non-local Fast Extraction from the CERN SPS at 100 and 440 GeV 392
 
  • F.M. Velotti, A. Alekou, W. Bartmann, E. Carlier, K. Cornelis, I. Efthymiopoulos, B. Goddard, L.K. Jensen, V. Kain, M. Kowalska, V. Mertens, R. Steerenberg
    CERN, Geneva, Switzerland
 
  The Long Straight Section 2 (LSS2) of the CERN SPS is connected with the North Area (NA), to which the beam to date has always been extracted using a resonant extraction technique. For new proposed short- and long-baseline neutrino experiments, a fast single turn extraction to this experimental area is required. As there are no kickers in LSS2, and the integration of any new kickers with the existing electrostatic septum would be problematic, a solution has been developed to fast extract the beam using non-local extraction with other SPS kickers. Two different kicker systems have been used, the injection kicker in LSS1 and the stronger extraction kicker in LSS6 to extract 100 and 440 GeV beam, respectively. For both solutions a large emittance beam was extracted after 5 or 9 full betatron periods. The concept and simulation details are presented with the analysis of the aperture and beam loss considerations and experimental results collected during a series of beam tests.  
 
MOPFI051 Beam Transfer Systems for the LAGUNA-LBNO Long Baseline Neutrino Beam from the CERN SPS 395
 
  • B. Goddard, W. Bartmann, I. Efthymiopoulos, Y. Papaphilippou, A.S. Parfenova
    CERN, Geneva, Switzerland
 
  For the Long Baseline neutrino facility under study at CERN (LAGUNA-LBNO) it is initially planned to extract a 400 GeV beam from the second long straight section in the SPS into the existing transfer channel TT20 leading to the North Area experimental zone, to a new target aligned with a far detector in Finland. In a second phase a new High-Power Proton Synchrotron (HPPS) accelerator is proposed, to give a 2 MW beam at about 50 GeV on the same target. In this paper the beam transfer systems required for the project are outlined, including the new sections of transfer line between the SPL, HPPS and SPS, and from the SPS to the target, and also the injection and extraction systems in the long straight section of the HPPS. The feasibility of a 4 GeV H injection system is discussed.  
 
TUPEA052 Design Study for a CERN Short Base-Line Neutrino Facility 1250
 
  • R. Steerenberg, M. Calviani, I. Efthymiopoulos, A. Ferrari, B. Goddard, R. Losito, M. Nessi, J.A. Osborne, L. Scibile, H. Vincke
    CERN, Geneva, Switzerland
  • P.R. Sala
    Istituto Nazionale di Fisica Nucleare, Milano, Italy
 
  A design study has been initiated at CERN for the conception and construction of a short base line neutrino facility, using a proton beam from the CERN Super Proton Synchrotron (SPS) that will be transferred to a new secondary beam production facility, which will provide a neutrino beam for experiments and detector R&D. This paper resumes the general layout of the facility together with the main primary and secondary beam parameters and the choices favoured for the neutrino beam production.  
 
TUPFI018 A Simplified Magnetic Field Tapering and Target Optimisation for the Neutrino Factory Capture System 1370
 
  • I. Efthymiopoulos, S.S. Gilardoni, O.M. Hansen, G. Prior
    CERN, Geneva, Switzerland
  • O.M. Hansen
    University of Oslo, Oslo, Norway
  • G. Prior
    University of Canterbury, Christchurch, New Zealand
 
  In the Neutrino Factory, a 4 MW proton beam with a kinetic energy between 5 and 15 GeV interacts with a liquid mercury jet target in order to produce pions that will decay to muons, which in turn decay to neutrinos. The baseline-capturing layout consists of a series of solenoids producing a tapered magnetic field from 20 T, near the target, down to 1.5 T at the entrance of the drift section where the captured pions decay into muons to produce a useful beam for the machine. In our alternative layout the magnetic field is rapidly squeezed from 20 T to 1.5T using only three solenoids. This layout showed to produce similar performance, having the advantage being simpler and could potentially be made more robust to radiation. Here we report on further optimization studies taking into account the complete path and shape fluctuations of the Hg-jet.  
 
TUPFI019 Magnet Misalignment Studies for the Front-end of the Neutrino Factory 1373
 
  • G. Prior, I. Efthymiopoulos
    CERN, Geneva, Switzerland
  • D.V. Neuffer, P. Snopok
    Fermilab, Batavia, USA
  • C.T. Rogers
    STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom
  • D. Stratakis
    BNL, Upton, Long Island, New York, USA
 
  In the Neutrino Factory Front-End the muon beam coming from the interaction of a high-power (4 MW) proton beam on a mercury jet target, is transformed through a buncher, a phase rotator and an ionization cooling channel before entering the downstream acceleration system. The muon Front-End channel is densely packed with solenoid magnets, normal conducting radio-frequency cavities and absorber windows (for the cooling section). The tolerance to the misalignment of the different components has to be determined in order on one hand to set the limits beyond which the performance of the Front-End channel would be degraded; on the other hand to optimize the design and assembly of the Front-End cells such that the component alignment can be checked and corrected for where crucial for the performance of the channel. In this paper we will show the results of the simulations of the Front-End channel performance where different components such as magnets, cavities have been randomly shifted or rotated. Detailed simulations have been done in G4BeamLine*. * T. J. Roberts et al. G4BeamLine 2.06 (2010) http://g4beamline.muonsinc.com/  
 
TUPFI020 Towards a Symmetric Momentum Distribution in the Muon Ionization Cooling Experiment 1376
 
  • O.M. Hansen
    University of Oslo, Oslo, Norway
  • A.P. Blondel
    DPNC, Genève, Switzerland
  • I. Efthymiopoulos, O.M. Hansen
    CERN, Geneva, Switzerland
 
  The Muon Ionization Cooling Experiment (MICE) is under development at Rutherford Appleton Laboratory (UK). It's a proof-of-principle experiment for ionization cooling, which is a prerequisite for a future Neutrino Factory(NF) or a Muon Collider. The muon beam is designed to have a symmetrical momentum distribution in the cooling channel of the NF. In the MICE beamline pions are captured by a quadrupole triplet, then pion momentum is selected by dipole 1 (D1) after which the pions decay to muons in the decay solenoid. After the decay solenoid, the muon beam momentum is selected by dipole 2 (D2), the beam is focused in two quadrupole triplets and is finally characterized by a set of detectors. By doing a D1-scan of the currents, where the optics parameters are scaled according to the pion momentum, from 238-450 MeV/c the muon momentum distribution is changed. In this paper simulation results from G4Beamline and real data from MICE are presented and compared.  
 
WEPME041 The Distance from CERN to LNGS 3016
 
  • M.A. Jones, I. Efthymiopoulos, D.P. Missiaen
    CERN, Geneva, Switzerland
 
  Obviously the distance between the CNGS Target at CERN and the LNGS Opera experiment cannot be measured directly and in fact requires the combination of three independent sets of measurements: two to link underground reference points at each site to corresponding points on the surface; and a third to link the surface points at both sites. Until the Opera results raised questions about the speed at which neutrinos travelled, the main alignment concern for the CNGS beamline had been an orientation problem -to ensure that the beamline arrived to within ~100 m of its target at LNGS. GPS measurements at the two sites, and the use of gyro-theodolite measurements in the tunnel at CERN, ensured that the absolute alignment of the beamline was established to the required accuracy. New determinations of the links between the surface and the tunnel were not considered necessary until interest grew in the distance between the sites, at which point additional measurement campaigns were organised in order to further reduce the uncertainty in the distance. Details of all these campaigns and the distance estimates will be given.  
 
THPFI053 A Feasibility Experiment of a W-powder Target in the HiRadMat Facility of CERN 3409
 
  • N. Charitonidis, I. Efthymiopoulos, A. Fabich
    CERN, Geneva, Switzerland
  • O. Caretta, T.R. Davenne, C.J. Densham, M.D. Fitton, P. Loveridge
    STFC/RAL, Chilton, Didcot, Oxon, United Kingdom
  • L. Rivkin
    EPFL, Lausanne, Switzerland
 
  Granular solid targets made of fluidized tungsten powder or static pebble bed of tungsten spheres, have been long proposed and are being studied as an alternative configurations towards high-power (>1MW of beam power) target systems, suitable for a future Super Beam or Neutrino Factory. Serving the lack of experimental data on this field, a feasibility experiment was performed in HiRadMat facility of CERN/SPS that tried in a pulse-by-pulse basis to address the effect of the impact of the SPS beam (440GeV/c) on a static tungsten powder target. Online instrumentation such as high-speed photography and Laser - Doppler Vibrometry was employed. Preliminary results show a powder disruption speed of less than 0.5 m/s while the disruption height appears to be scaling proportionally with the beam intensity. Other analysis results will be discussed.  
 
THPFI055 First Year of Operations in the HiRadMat Irradiation Facility at CERN 3415
 
  • A. Fabich, N. Charitonidis, N. Conan, K. Cornelis, D. DePaoli, I. Efthymiopoulos, S. Evrard, H. Gaillard, J.L. Grenard, M. Lazzaroni, A. Pardons, Y.D.R. Seraphin, C. Theis, K. Weiss
    CERN, Geneva, Switzerland
  • N. Charitonidis
    EPFL, Lausanne, Switzerland
 
  HiRadMat (High Irradiation to Materials) is a new facility at CERN constructed in 2011, designed to provide high-intensity pulsed beams to an irradiation area where material samples as well as accelerator component assemblies can be tested. The facility uses a 440 GeV proton beam extracted from the CERN SPS with a pulse length of 7.2 μs, to maximum pulse energy of 3.4MJ. For 2012, the first year of operations of the facility, nine experiments were scheduled and completed data-taking successfully. The experience gained in operating this unique facility, along with highlights of the experiments and the instrumentation developed for online measurements are reported.  
 
THPFI056 Design Study for a Future LAGUNA-LBNO Long-baseline Neutrino Facility at CERN 3418
 
  • I. Efthymiopoulos, J. Alabau-Gonzalvo, A. Alekou, F. Antoniou, M. Benedikt, M. Calviani, A. Ferrari, R. Garoby, F. Gerigk, S.S. Gilardoni, B. Goddard, A. Kosmicki, C. Lazaridis, J.A. Osborne, Y. Papaphilippou, A.S. Parfenova, E.N. Shaposhnikova, R. Steerenberg, P. Velten, H. Vincke
    CERN, Geneva, Switzerland
 
  A design study for a long baseline neutrino oscillation experiment (LBNO) with a new conventional neutrino beamline facility (CN2PY) at CERN was initiated in September 2011, supported by EU/FP7 funds. The beam will be aimed at a next generation deep-underground neutrino observatory located at the Pyhasalmi (Finland) mine at a distance of 2300 km. In an initial phase the CN2PY facility will use a 400 GeV beam extracted from SPS up to a maximum power of 750 kW, and in a second phase a 2 MW beam of about 50 GeV produced by a new High-Power Proton Synchrotron accelerator using the LP-SPL as injector also under design. The paper will focus on the design challenges of this MW-class facility and on the optimization studies of the secondary beam elements (target and horns) to produce a neutrino beam spectrum that matches best the experimental requirements for neutrino flavor oscillations and CP-violation tests. The challenges and bottlenecks in the existing CERN accelerator complex to produce the high-intensity beams foreseen for this facility at the initial phase are discussed.  
 
THPWO081 Design Options of a High-power Proton Synchrotron for LAGUNA-LBNO 3948
 
  • Y. Papaphilippou, J. Alabau-Gonzalvo, A. Alekou, F. Antoniou, M. Benedikt, I. Efthymiopoulos, R. Garoby, F. Gerigk, B. Goddard, C. Lazaridis, A.S. Parfenova, E.N. Shaposhnikova, R. Steerenberg
    CERN, Geneva, Switzerland
 
  Design studies have been initiated at CERN, exploring the prospects of future high-power proton beams for producing neutrinos, within the LAGUNA-LBNO project. These studies include the design of a 2 MW high-power proton synchrotron (HP-PS) using the LP-SPL as injector. This paper resumes the design options under study in order to reach this high power, and their implications regarding layout, magnet technology beam loss control and RF considerations. Optics optimization studies are also presented including beam transfer and collimation considerations.