Author: Migliorati, M.
Paper Title Page
MOPPP069 First Measurements of COLDDIAG: A Cold Vacuum Chamber for Diagnostics 720
 
  • S. Gerstl, T. Baumbach, S. Casalbuoni, A.W. Grau, M. Hagelstein, T. Holubek, D. Saez de Jauregui
    Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
  • R. Bartolini, M.P. Cox, J.C. Schouten, R.P. Walker
    Diamond, Oxfordshire, United Kingdom
  • M. Migliorati, B. Spataro
    INFN/LNF, Frascati (Roma), Italy
  • I.R.R. Shinton
    UMAN, Manchester, United Kingdom
  
  Superconductive insertion devices can reach, for the same gap and period length, higher fields with respect to permanent magnet insertion devices. One of the still open issues for the development of superconductive insertion devices, is the understanding of the heat intake from the electron beam. COLDDIAG, a cold vacuum chamber for diagnostics was designed and built specifically for this purpose. With the equipped instrumentation, which covers temperature sensors, pressure gauges, mass spectrometers as well as retarding field analyzers it is possible to measure the beam heat load, total pressure, gas content as well as the flux of particles hitting the chamber walls. Here we report about the preliminary measurements and results of COLDDIAG installed in the Diamond storage ring.  
 
TUOBB01 A European Proposal for the Compton Gamma-ray Source of ELI-NP 1086
 
  • L. Serafini, I. Boscolo, F. Broggi, V. Petrillo
    Istituto Nazionale di Fisica Nucleare, Milano, Italy
  • O. Adriani, G. Graziani, G. Passaleva
    INFN-FI, Sesto Fiorentino, Italy
  • S. Albergo, A. Tricomi
    INFN-CT, Catania, Italy
  • D. Alesini, M.P. Anania, A. Bacci, R. Bedogni, M. Bellaveglia, C. Biscari, R. Boni, M. Boscolo, M. Castellano, E. Chiadroni, A. Clozza, E. Di Pasquale, G. Di Pirro, A. Drago, A. Esposito, M. Ferrario, A. Gallo, G. Gatti, A. Ghigo, F. Marcellini, C. Maroli, G. Mazzitelli, E. Pace, L. Pellegrino, R. Ricci, M. Serio, F. Sgamma, B. Spataro, A. Stecchi, A. Stella, P. Tomassini, C. Vaccarezza, S. Vescovi, F. Villa
    INFN/LNF, Frascati (Roma), Italy
  • D. Angal-Kalinin, J.A. Clarke, B.D. Fell, A.R. Goulden, J.D. Herbert, S.P. Jamison, P.A. McIntosh, R.J. Smith, S.L. Smith
    STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
  • P. Antici, M. Coppola, L. Lancia, A. Mostacci, L. Palumbo
    URLS, Rome, Italy
  • N. Bliss, B.G. Martlew
    STFC/DL, Daresbury, Warrington, Cheshire, United Kingdom
  • P. Cardarelli, M. Gambaccini
    INFN-Ferrara, Ferrara, Italy
  • L. Catani, A. Cianchi
    INFN-Roma II, Roma, Italy
  • I. Chaikovska, O. Dadoun, A. Stocchi, A. Variola, Z.F. Zomer
    LAL, Orsay, France
  • C. De Martinis
    INFN/LASA, Segrate (MI), Italy
  • F. Druon, P. Fichot
    ILE, Palaiseau Cedex, France
  • E. Iarocci
    University of Rome "La Sapienza", Rome, Italy
  • M. Migliorati
    Rome University La Sapienza, Roma, Italy
  • A.-S. Müller
    IN2P3, Paris, France
  • V. Nardone
    Università di Roma I La Sapienza, Roma, Italy
  • C. Ronsivalle
    ENEA C.R. Frascati, Frascati (Roma), Italy
  • M. Veltri
    Uniurb, Urbino (PU), Italy
  
  A European proposal is under preparation for the Compton gamma-ray Source of ELI-NP. In the Romanian pillar of ELI (the European Extreme Light Infrastructure) an advanced gamma-ray beam is foreseen, coupled to two 10 PW laser systems. The photons will be generated by Compton back-scattering in the collision between a high quality electron beam and a high power laser. A European collaboration formed by INFN, Univ. of Roma La Sapienza, Orsay-LAL of IN2P3, Univ. de Paris Sud XI and ASTeC at Daresbury, is preparing a TDR exploring the feasibility of a machine expected to achieve the Gamma-ray beam specifications: energy tunable between 1 and 20 MeV, narrow bandwidth (0.3%) and high spectral density, 104 photons/sec/eV. We will describe the lay-out of the 720 MeV RF Linac and the collision laser with the associated optical cavity, as well as the optimized beam dynamics to achieve maximum phase space density at the collision, taking into account beam loading and beam break-up due to the acceleration of long bunch trains. The predicted gamma-ray spectra will be evaluated as the gamma photons collimators background. An option for electron bunches recirculation will also be illustrated.  
slides icon Slides TUOBB01 [5.099 MB]  
 
WEPPR051 Issues for a Multi-bunch Operation with SPARC C-band Cavities 3042
 
  • A. Mostacci, M. Migliorati, L. Palumbo
    URLS, Rome, Italy
  • D. Alesini, B. Spataro, C. Vaccarezza
    INFN/LNF, Frascati (Roma), Italy
  
  SPARC C-band traveling wave cavities were originally designed for the SPARC energy upgrade in the single bunch operation mode. In the context of a gamma source based on Compton backscattering and based on the SPARC C-band technology, we investigated the issues related to the use of these structures in the multi-bunch operation mode. Several beam configurations have been considered and the effects of transverse and longitudinal long range wakefields on beam dynamics have been studied. In the paper we present the results of these studies and, in particular, the issues related to transverse beam break-up that could prevent the multi-bunch operation. Possible HOM damped structures are also proposed.  
 
WEPPR062 The Mode Matching Method Applied to Beam Coupling Impedance Calculations of Finite Length Devices 3069
 
  • N. Biancacci, E. Métral, B. Salvant
    CERN, Geneva, Switzerland
  • M. Migliorati, L. Palumbo
    URLS, Rome, Italy
  • V.G. Vaccaro
    Naples University Federico II and INFN, Napoli, Italy
  
  The infinite length approximation is often used to simplify the calculation of the beam coupling impedance of accelerator elements. This is expected to be a reasonable assumption for devices whose length is greater than the transverse dimension but may be less accurate approximation for segmented devices. This contribution presents the study of the beam coupling impedance in the case of a finite length device: a cylindrical cavity loaded with a toroidal slab of material. In order to take into account the finite length we will decompose the field in the cavity and in the beam pipe into a set of orthonormal modes and apply the mode matching method to obtain the impedance. To validate our method, we will present comparisons between analytical formulas and 3D electromagnetic CST simulations as well as applications to the impedance of short beam pipe inserts, where the longitudinal and transverse dimensions are difficult to model in numerical simulations.