Author: Michelato, P.
Paper Title Page
MOPVA040 Status of the ESS Elliptical Cryomodules at CEA Saclay 945
 
  • P. Bosland, C. Arcambal, F. Ardellier, S. Berry, A. Bouygues, A. Bruniquel, E. Cenni, J.-P. Charrier, C. Cloué, G. Devanz, F. Éozénou, T. Hamelin, X. Hanus, P. Hardy, C. Marchand, O. Piquet, J. Plouin, J.P. Poupeau, T. Trublet
    CEA/DRF/IRFU, Gif-sur-Yvette, France
  • G. Costanza
    Lund University, Lund, Sweden
  • C. Darve
    ESS, Lund, Sweden
  • P. Michelato
    INFN/LASA, Segrate (MI), Italy
  • G. Olivier
    IPN, Orsay, France
  • F. Peauger
    CEA/DSM/IRFU, France
 
  The first ESS prototype cryomodule with medium beta cavities named M-ECCTD is being assembled at CEA Saclay. The Q curves of the 4 cavities mounted inside the cryomodule are presented, and the four power couplers have been conditioned at high power before their assembly onto the cavity string. Completion of the M-ECCTD assembly outside clean room is in progress as well as the finalization of the RF power test stand preparation. RF power tests of the M-ECCTD will be performed during summer 2017. CEA is preparing the production of the ESS medium and high beta cryomodules of the series before the test of the M-ECCTD and the contracts for the procurement of the most critical components have already been signed  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-MOPVA040  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPVA060 Fabrication and Treatment of the ESS Medium Beta Prototype Cavities 1003
 
  • L. Monaco, A. Bellandi, M. Bertucci, A. Bignami, A. Bosotti, J.F. Chen, P. Michelato, R. Paparella, D. Sertore
    INFN/LASA, Segrate (MI), Italy
  • C. Pagani
    Università degli Studi di Milano & INFN, Segrate, Italy
  • S. Pirani
    ESS, Lund, Sweden
 
  In view of the Medium Beta series cavities production at the industry for the European Spallation Source project, INFN Milano - LASA design prototypes have been fully produced at Ettore Zanon S.p.A. with our supervision. Based on our experience on the production of 1.3 GHz and 3.9 GHz E-XFEL series cavities, we set-up and applied an external quality control activity of the overall production of the prototype cavity, starting from the row materials to the ready to be tested cavity. In this paper, we report the strategy we have adopted on the overall production, mechanical and surface treatments, frequency measurement of subcomponents and cavities and the obtained results.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-MOPVA060  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPVA061 Quench and Field Emission Diagnostics for the ESS Medium-Beta Prototypes Vertical Tests at LASA 1007
 
  • M. Bertucci, A. Bellandi, A. Bignami, A. Bosotti, J.F. Chen, P. Michelato, L. Monaco, R. Paparella, D. Sertore
    INFN/LASA, Segrate (MI), Italy
  • C. Pagani
    Università degli Studi di Milano & INFN, Segrate, Italy
  • S. Pirani
    ESS, Lund, Sweden
 
  In order to investigate the possible causes of premature thermal breakdown and performance degradation, several diagnostic techniques have been employed during the vertical tests of the Fine and Large Grain ESS Medium Beta prototypes cavities. The whole equipment, which includes second sound, fast thermometry, photodiode x ray detectors and an external NaI scintillator, is here described and the results so far obtained during the vertical tests presented.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-MOPVA061  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPVA062 Test, Diagnostics and Computed Tomographic Inspection of a Large Grain 3.9 GHz Prototype Cavity 1011
 
  • M. Bertucci, A. Bignami, A. Bosotti, J.F. Chen, C.G. Maiano, P. Michelato, L. Monaco, R. Paparella, P. Pierini, D. Sertore
    INFN/LASA, Segrate (MI), Italy
  • G. Ciovati, G.R. Myneni
    JLab, Newport News, Virginia, USA
  • C. Pagani
    Università degli Studi di Milano & INFN, Segrate, Italy
 
  A large grain 3.9 GHz prototype cavity made of RRR = 105 ±10 has been tested at LASA. The cavity suffered of quench at moderate levels of accelerating field, for all nine fundamental pass-band modes. Several diagnostic techniques have been employed to determine the quench positions, which occur close to significant grain-boundary steps, visible from the external cavity surface. The cavity has been scanned with a high resolution X-ray tomographic machine, confirming the existence of remarkable topographic features on the inner RF surface at the suspected quench positions. A strategy for a future surface treatment for recover the cavity performances is here presented.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-MOPVA062  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPVA063 Vertical Tests of ESS Medium Beta Prototype Cavities at LASA 1015
 
  • A. Bosotti, A. Bellandi, M. Bertucci, A. Bignami, J.F. Chen, C.G. Maiano, P. Michelato, L. Monaco, R. Paparella, P. Pierini, D. Sertore
    INFN/LASA, Segrate (MI), Italy
  • C. Pagani
    Università degli Studi di Milano & INFN, Segrate, Italy
  • S. Pirani
    ESS, Lund, Sweden
 
  In the framework of the INFN activity related to the European Spallation Source collaboration, the LASA infrastructure has been renewed to allow the qualification, in its vertical cryostat, of the 704 MHz medium beta cavity prototypes. A new cryogenic insert has been realized, fully equipped with dedicated mechanical supports, vacuum, thermal sensors and quench diagnostic systems. The RF test station has been upgraded as well with a new PLL electronics rack. The first beta 0.67 cavity prototype designed and produced by INFN Milano has been successfully cold tested at 2.0 K temperature, outperforming the ESS specifications. The technical features of LASA infrastructure, the design of novel components and the experimental results of cavities cold-tests are thoroughly described in this paper.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-MOPVA063  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPVA064 Multipacting Study in INFN-LASA ESS Medium-Beta Cavity 1019
 
  • J.F. Chen, M. Bertucci, A. Bosotti, P. Michelato, L. Monaco, C. Pagani, R. Paparella, D. Sertore
    INFN/LASA, Segrate (MI), Italy
  • S. Pirani
    ESS, Lund, Sweden
 
  We present Multipacting studies in ESS Medium-Beta cavities of INFN-LASA design with both simulation and experimental results. The simulation on the ideal cavity shape with both FishPact and MultiPac2.1 codes shows that multipacting appears in a very small region near equator where the weld seam exists. A simulation with more realistic cavity shape considering the weld seam at cell equators has also been done out showing similar results for end cell but a remarkable mitigation for inner cell. During the vertical tests at LASA, Multipacting is frequently observed but with no limitation to the cavity performance, which well confirms the MP predicted by the simulations.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-MOPVA064  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPVA068 Experience on Design, Fabrication and Testing of a Large Grain ESS Medium Beta Prototype Cavity 1027
 
  • D. Sertore, A. Bellandi, M. Bertucci, A. Bignami, A. Bosotti, J.F. Chen, C.G. Maiano, P. Michelato, L. Monaco, R. Paparella, P. Pierini
    INFN/LASA, Segrate (MI), Italy
  • C. Pagani
    Università degli Studi di Milano & INFN, Segrate, Italy
  • S. Pirani
    ESS, Lund, Sweden
 
  We report on the design, fabrication and testing of an ESS Medium Beta prototype cavity made with Large Grain Niobium sheets sliced from an ingot provided by CBMM. The peculiar choices during the fabrication process related to the Large Grain Niobium material are described. We present also the results of the cavity test at cryogenic temperature and the dedicated quench diagnostic.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-MOPVA068  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPVA090 ESS Superconducting RF Collaboration 1068
 
  • C. Darve, H. Danared, N. Elias, N.F. Hakansson, M. Lindroos, C.G. Maiano, F. Schlander
    ESS, Lund, Sweden
  • F. Ardellier, P. Bosland
    CEA/DRF/IRFU, Gif-sur-Yvette, France
  • S. Bousson, G. Olry
    IPN, Orsay, France
  • M. Ellis, A.E. Wheelhouse
    STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
  • L. Hermansson, R.J.M.Y. Ruber
    Uppsala University, Uppsala, Sweden
  • P. Michelato, D. Sertore
    INFN/LASA, Segrate (MI), Italy
 
  The European Spallation Source (ESS) project is a neutron-scattering facility, currently under construction by a partnership of at least 17 European countries, with Sweden and Denmark as host nations. The ESS was designated a European Research Infrastructure Consortium, or ERIC, by the European Commission in October of 2015. Scientists and engineers from 50 different countries are members of the workforce in Lund who participate in the design and construction of the European Spallation Source. In complement to the local workforce, the superconducting RF linear accelerator is being prototyped and will be constructed based on a collaboration with European institutions: CEA-Saclay, CNRS-IPN Orsay, INFN-LASA, STFC-Daresbury, Uppsala and Lund Universities. After a description of the ESS collaborative project and its in-kind model for the SRF linac, this article will introduce the linac component first results.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-MOPVA090  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPVA091 Investigation of HOM Frequency Shifts Induced by Mechanical Tolerances 1071
 
  • S. Pirani, M. Eshraqi, M. Lindroos
    ESS, Lund, Sweden
  • A. Bosotti, J.F. Chen, P. Michelato, C. Pagani, R. Paparella, D. Sertore
    INFN/LASA, Segrate (MI), Italy
  • T.P.Å. Åkesson
    Lund University, Department of Physics, Lund, Sweden
 
  We present Higher Order Mode (HOM) studies on ESS Medium-Beta cavity of INFN-LASA design, including both simulation and measurement results. Mechanical tolerances of the fabrication process might shift HOMs frequencies toward harmonics of the bunch frequency. Both simulation and measurements at room and cryogenic temperature show that INFN LASA cavity is fully compatible with ESS requirements.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-MOPVA091  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THOBB3 ESS SRF Linear Accelerator Components Preliminary Results and Integration 3666
 
  • C. Darve, N. Elias, C.G. Maiano, F. Schlander
    ESS, Lund, Sweden
  • C. Arcambal, G. Devanz, F. Peauger
    CEA/DRF/IRFU, Gif-sur-Yvette, France
  • E. Cenni
    CEA/IRFU, Gif-sur-Yvette, France
  • G. Costanza
    Lund University, Lund, Sweden
  • P. Duthil, G. Olry, D. Reynet
    IPN, Orsay, France
  • L. Hermansson
    Uppsala University, Uppsala, Sweden
  • P. Michelato, D. Sertore
    INFN/LASA, Segrate (MI), Italy
 
  The European Spallation Source (ESS) is a pan-European project and one of world's largest research infrastructures based on neutron sources. This collaborative project is funded by a collaboration of 17 European countries and is under construction in Lund, Sweden. The 5 MW, 2.86 ms long pulse proton accelerator has a repetition frequency of 14 Hz (4 % duty cycle), and a beam current of 62.5 mA. The Superconducting Radio-Frequency (SRF) linac is composed of three families of Superconducting Radio-Frequency (SRF) cavities, which are being prototyped, counting the spoke resonators with a geometric beta of 0.5, medium-beta elliptical cavities (betag=0.67) and high-beta elliptical cavities (betag=0.86). After a description of the ESS linear accelerator layout, this article will focus on the recent progress towards integration of the first test results of the main critical components to be assembled in cryomodules, then in the ESS tunnel.  
slides icon Slides THOBB3 [25.611 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-THOBB3  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)