JRA on Sc cavities and Cryomodule for a Pulsed proton Linac

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JRA on Sc cavities and Cryomodule for a Pulsed
proton Linac
R. Garoby for S. Chel, E. Ciappala, R. Duperrier,
F. Gerigk, R. Losito, V. Parma, B. Petersen, P.
Pierini, J. Tuckmantel, M. Vretenar, W.
Weingarten

• Motivation
• Work Packages
• Partners resources

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Motivation

• A superconducting linac represents today the best
  solution for the acceleration of high intensity,
  high brightness and high beam power proton beams
  up to a few GeV Foreseen European projects
  planning to use a superconducting linac for
  accelerating protons EURISOL, ESS, ADS,
  LPSPL/SPL at CERN.
• Based on the results of the HIPPI JRA inside CARE
  which has studied the low energy part of pulsed
  proton linacs (up to 200 MeV) and using
  extensively the technology developed for the ILC,
  the proposal is to extend the development to the
  acceleration system above 200 MeV for a pulsed
  proton linac, using superconducting elliptic
  multi-cell cavities.
• One important goal is to prepare for a start of
  construction of the LPSPL at CERN in 2012, as
  part of the planned overall refurbishment of the
  injector complex of LHC.

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WP1 Management Communication
Goals

• management of the JRA
• organization of communication inside and
  dissemination outside the JRA (publications,
  internet etc.)
• link with other JRAs as well as with other
  European projects and integration of the relevant
  results
• coordination of the technical debates and
  conclusion on suitable technologies

Year 1 Year 1 Year 1 Year 1 Year 2 Year 2 Year 2 Year 2 Year 3 Year 3 Year 3 Year 3 Year 4 Year 4 Year 4 Year 4
Coord. meetings / workshops X X X X
Reports X X X X
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WP2 Studies computations
Subjects

• HOM in cavities
• analysis of the effect on the beam,
• study of the possible means of compensation,
• specification of solution (e.g. HOM dampers).
• Study of the propagation in the high energy
  sections of the beam mismatch induced by
  transient neutralization at low energy
• simulation of the neutralization in the front-end
  (steady state and transient),
• simulation of the transport of this transverse
  modulated beam pulse in the rest of the
  accelerator,
• analysis of possible corrective actions.
• Study of beam centering and matching in the high
  energy sections using BPMs and/or dipolar modes
  in the cavity
• development of a centering correction method
  using the dipolar moment,
• development of a matching method using the
  quadrupolar moment.

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WP2 Beam dynamics computations
Planning
Recommendations for the cavity design (WP3)
Year 1 Year 1 Year 1 Year 1 Year 2 Year 2 Year 2 Year 2 Year 3 Year 3 Year 3 Year 3 Year 4 Year 4 Year 4 Year 4
HOMs x x x x x x
Neutralization x x x x x x
Beam matching and alignment with BPMs x x x x
Recommendations for the design of the prototype
cryomodule (WP4)
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WP3 Superconducting cavities

• Goal
• development of superconducting elliptic
  multi-cell cavities meeting the SPL
  specifications for b1 (25 MV/m). The high power
  tests will be made at the CEA-Saclay using
  CRYHOLAB and the 704 MHz RF system installed in
  the frame of HIPPI.
• Design phase
• optimization of cavity shape,
• optimization of geometrical beta (usually the
  optimum ßgeom lt ßparticle),
• Hardware tests (Cryholab - Saclay)
• measurement of each cavity in a test cryostat (Q
  as a function of temperature (2 K, 4.5 K) and
  electric gradient)
• measurements with a matched power source
  (low-power) and high-power tests (up to 1 MW),
• determination of the maximum gradient as a
  function of repetition rate (duty cycle).

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WP3 Superconducting cavities

• Challenges
• high gradient at relatively low frequency,
• pulsed mode of operation at high repetition rate
  (50 Hz)

Planning
Year 1 Year 1 Year 2 Year 2 Year 2 Year 2 Year 3 Year 3 Year 4 Year 4 Year 4
Cavities Design Construction of cav. 1 Construction of cav. 1 Test cav.1 Study improved design Study improved design Construction of cav.2 Test cav.2 Integ. in cryostat
Couplers Design Construction Construction Construction
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WP4 Multi-cavity cryostat

• Goals
• design of the complete multi-cavity cryostat for
  the SPL ,
• construction of a prototype housing the 2
  cavities built in WP2 and tuners equipped with
  fast piezo devices as developed in the frame of
  HIPPI,
• characterization of the ensemble in the new
  multi-purpose test place for sc modules at CERN
  (JRA SuRFTeC).

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WP4 Multi-cavity cryostat

• Design phase
• design of the full 8-cell SPL cryo-module for the
  SPL, adapting the TESLA/ILC cryo-modules to 704
  MHz,
• adaptation of the design of the cryo-module to
  the construction of the prototype hosting 2
  cavities,
• assessment of the effect on the cavities of the
  magnetic stray fields of the sc quadrupole
  doublet,
• stiffness simulations, vibrational analysis
• Hardware tests (CERN)
• pulsed high-power tests with up to 1 MW per
  cavity Q, gradients
• measurement of the static and dynamic cryogenic
  losses,
• test of the RF set-up, needed for the SPL 4 or 5
  MW klystrons (prototypes from industry),
  high-power circulators, splitters, phase
  shifters, etc,
• pulsed operation of multiple cavities driven by a
  single RF source implementation and test of a 2
  cavities version of the RF architecture
  recommended after the study in the CNI for SLHC.

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WP4 Multi-cavity cryostat

• Challenges
• Minimization of heat loss and construction cost
• Control of mechanical vibrations

Planning
Year 1 Year 1 Year 1 Year 1 Year 2 Year 2 Year 2 Year 2 Year 3 Year 3 Year 3 Year 3 Year 4 Year 4 Year 4 Year 4
Design of long cryostat for 8 cavities X X X X X X X X
Construction of a cryostat prototype housing 2 cavities X X X X X X X X
Test of cryostat prototype X X X
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Partners and resources
WP1 WP2 WP3 WP4
CERN 24 m.m 0.06 MEuros 6 m.m 6 m.m 60 m.m 0.5 MEuros
CEA-Saclay 6 m.m 0.03 MEuros 18 m.m 69 m.m 0.5 MEuros 12 m.m
DESY ? 0.02 MEuros ? ? 4 m.m ?
IN2P3-Orsay ? 0.03 MEuros ? ? gt8 m.m
INFN-Milano INFN participation would make great sense (continuation of HIPPI etc.) and be highly valuable INFN participation would make great sense (continuation of HIPPI etc.) and be highly valuable INFN participation would make great sense (continuation of HIPPI etc.) and be highly valuable INFN participation would make great sense (continuation of HIPPI etc.) and be highly valuable
TOTAL gt24 m.m 0.16 MEuros gt24 m.m gt75 m.m 0.5 MEuros gt84 m.m 0.5 MEuros
gt207 m.m 1.16 MEuros