Upgrading Existing High Power Proton Linacs

Europe/Stockholm
Tänkartanken (European Spallation Source ERIC)

Tänkartanken

European Spallation Source ERIC

Tunavägen 24, Lund, Sweden
Description
The European Spallation Source ERIC (ESS) and Uppsala University are organizing an International Workshop on Upgrading Existing High Power Proton Linacs to be held in the Tänkartanken Seminar Room at the premise of ESS at Tunavägen 24, Lund, Sweden 8-9 November 2016. The workshop will address the possibilities and limitations for further increasing the power of existing linear accelerators. Increasing the strength of the accelerating field or increasing the pulse current will increase both the instantaneous and average beam power. Increasing the instantaneous power only may be done by using an accumulator ring to compress the pulses which requires the acceleration of H- ions in the linac. The need to accelerate H- ions might in the longer term be alleviated by using a Fixed-Field Alternating Gradient Accelerator (FFAG) ring as accumulator ring. Increasing the average power only can be made by by increasing the pulse repetition rate or increasing the pulse length. The workshop will consist of the following four half-day sessions: 1. Pulse compressor rings Session chair: Elena Wildner CERN, elena.wildner@cern.ch 2. Increasing the accelerating field strength, the pulse current or the beam energy Session chair: Frank Gerigk CERN, frank.gerigk@cern.ch 3. H- sources and H- acceleration in proton linacs Session chair: Alessandra Lombardi CERN, alessandra.lombardi@cern.ch 4. Increasing the pulse repetition rate or the pulse length Session chair: Mark Middendorf SNS, middendorfme@ornl.gov There will be invited and contributed talks and ample time for discussions. Registration for participation in the workshop is free and open till 15 October 2016. Applications to give a contributed talk of 15(talk) +10 (discussion) minutes at the workshop, containing the title and a brief abstract of the talk, should be emailed to the appropriate session convener (see above) by latest 15 October. Members of the International Program Advisory Committe: Hamid Aït Abderrahim (MYRRAH), Sébastien Bousson (IPN Orsay), John Galambos (SNS), Frank Gerigk (CERN), Lars Groening (GSI), Kazuo Hasegawa (J-PARC), Stuart Henderson (ANL), Erk Jensen (CERN), Mats Lindroos (ESS), Alessandra Lombardi (CERN), Alban Mosnier (CEA), Maurizio Vretenar (CERN), Frank Zimmermann (CERN) Members of the Local Organizing Committee: Tord Ekelof (FREIA, Uppsala), co-chair, Mohammad Eshraqi (ESS, Lund), co-chair, Yngve Levinsen (ESS, Lund), Roger Ruber (FREIA, Uppsala), Caroline Prabert (ESS, Lund), Inga Tejedor (ESS, Lund), Elena Wildner (CERN, Geneva)
  • Tuesday, 8 November
    • 09:30 11:30
      Session 1: Pulse compressor rings Tänkartanken

      Tänkartanken

      European Spallation Source ERIC

      Tunavägen 24, Lund, Sweden

      a) High Space Charge rings
      b) H- injection with laser stripping instead of foils
      c) Lossless injection into rings without charge exchange
      d) FFAGs as a way towards high space charge rings

      Convener: Dr Elena Wildner (CERN)
      • 09:30
        Accumulator: introduction and status of design and simulations 25m
        Speaker: Maja Olvegård
        Slides
      • 09:55
        Design of high intensity proton rings 25m
        Speaker: Shinji Machida
        Slides
      • 10:20
        FFAGs for high intensity accumulator 25m
        Speaker: Jaroslaw Pasternak
        Slides
      • 10:45
        Coffee break 20m
      • 11:05
        Two-plane multiturn injection 25m
        Speaker: Chris Prior
        Slides
    • 11:30 13:00
      LUNCH 1h 30m Inspira Restaurant (Medicon Village)

      Inspira Restaurant

      Medicon Village

    • 13:00 16:00
      Session 2: Increasing the accelerating field strength, the pulse current, or the beam energy Tänkartanken

      Tänkartanken

      European Spallation Source ERIC

      Tunavägen 24, Lund, Sweden

      a) Beam dynamics limitations from increasing the current (space charge limits, halo development increased H-stripping)
      b) Equipment upgrades for reliable operations (e.g. klystrons/modulators, cryogenic cooling capacity)
      c) SRF cavity issues: structure improvements, conditioning, in-situ repairs, retrofits, operational experience/margins with existing SRF cavities, Lorentz-force detuning compensation
      d) Power coupler limitations

      Convener: Dr Frank Gerigk (CERN)
      • 13:00
        Introduction: Potential for gradient, current, or energy increase 25m
        Speaker: Frank Gerigk
        Slides
      • 13:25
        Power upgrade plane of J-PARC Linac and loss estimation 25m
        Speaker: Tomofumi Maruta
        Slides
      • 13:50
        Gradient limitations in pulsed SC cavities, imposed by power couplers, RF systems, Lorentz force detuning compensation 25m
        Speaker: Franck Peauger
        Slides
      • 14:15
        Linac upgrade scenarios for the RAL neutron source 25m
        Speaker: Ciprian Plostinar
        Slides
      • 14:40
        Coffee break 30m
      • 15:10
        Upgrades to the Spallation Neutron Source (SNS) Linac to Support the Second Target Station (STS) 25m
        Speaker: Mark Middendorf
        Slides
      • 15:35
        Gradient increase in SC cavities via plasma processing 25m
        Speaker: Marc Doleans
        Slides
    • 19:00 22:00
      Dinner in or outside Lund 3h TBC (Lund city centre or outside)

      TBC

      Lund city centre or outside

      If we have dinner outside Lund there will be a bus taking you there and back to the hotels again in the evening.

  • Wednesday, 9 November
    • 09:00 11:35
      Session 3: H- sources and H- acceleration in proton linacs Tänkartanken

      Tänkartanken

      European Spallation Source ERIC

      Tunavägen 24, Lund, Sweden

      a) Design choices with upgrade capability
      b) Intrabeam stripping in H- linacs
      c) Beam dynamics and simulation limitations
      d) Challenges in acceleration of H- and protons in the same linac

      Conveners: Alessandra Lombardi (CERN), Giulia Bellodi
      • 09:00
        H- source - challenges in terms of emittance and current, upgradability 25m
        Speaker: Shixian Peng
        Slides
      • 09:25
        Status and numerical study of J-PARC RF H- source 25m
        Speaker: Takanori Shibata
        Slides
      • 09:50
        Coffee break 30m
      • 10:20
        Flexibility for upgrade and design choices for proton linacs 25m
        Speaker: Dr Mats Lindroos (ESS AB)
      • 10:45
        H- stripping 25m
        Speaker: Deepak Raparia
        Slides
      • 11:10
        Characterization of a high intensity beam 25m
        Speaker: Phi Nghiem
        Slides
    • 11:35 13:00
      LUNCH 1h 25m Inspira Restaurant (Medicon Village)

      Inspira Restaurant

      Medicon Village

    • 13:00 14:45
      Session 4: Increasing the pulse repetition rate or the pulse length Tänkartanken

      Tänkartanken

      European Spallation Source ERIC

      Tunavägen 24, Lund, Sweden

      a) Loss detection, control, mitigation from duty cycle increase
      b) Cryoload at increased duty factor
      c) Challenges and needs on RF generation and distribution at increased power
      d) RF structure cooling limitations (e.g. copper structures and couplers)
      e) RF source robustness at higher duty factor
      f) Utility infrastructure issues

      Convener: Mark Middendorf (SNS)
      • 13:00
        Doubling the Beam Power of 45 Year Old H- Linac at Brookhaven 25m
        Speaker: Deepak Raparia
        Slides
      • 13:25
        Adaptation of ILC-type Cryo-module for CW Operation at LCLS-II: Issues, Solutions and Results 25m
        Speaker: Vyacheslav Yakovlev
        Slides
      • 13:50
        Challenges and Accomplishments in the 201 MHz RF System Upgrade at LANSCE 25m
        Speaker: Joseph Bradley III
        Slides
      • 14:15
        Coffee break 30m
    • 14:45 16:25
      Session 5: Concluding remarks by the session chairs Tänkartanken

      Tänkartanken

      European Spallation Source ERIC

      Tunavägen 24, Lund, Sweden

      a) Session 1
      b) Session 2
      c) Session 3
      d) Session 4

      • 14:45
        Summary session 1 20m
        Speaker: Dr elena wildner (CERN)
      • 15:05
        Summary Session 2 20m
        Speaker: Dr Frank Gerigk (CERN)
        Slides
      • 15:25
        Summary session 3 20m
        Speaker: Giulia Bellodi (CERN)
        Slides
      • 15:45
        Summary session 4 20m