SPL PDAC example

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LINAC-BASED PROTON DRIVER

• Introduction
• SPLPDAC example
• Elements of comparison Linacs / Synchrotrons

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Introduction

• All proton driver begin with a linear
  accelerator. In a Linac-based driver, all
  acceleration is done in the Linac. However a
  fixed energy synchrotron is still needed for
  accumulation and bunch compression.
• At low energy, it makes sense to only accelerate
  in a linac. Progress in sc resonators are
  reducing cost. However, at high energy (gt5-8 GeV
  ?), a linac will anyhow be too costly.
• What is the limit energy for selecting
  acceleration in the synchrotron ?
• Other arguments ?

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SPL PDAC 1/3
SPL (CDR2) characteristics
Ion species H-
Kinetic energy 3.5 GeV
Mean current during the pulse 40 (30 ?) mA
Mean beam power 4 MW
Pulse repetition rate 50 Hz
Pulse duration 0.57 (0.76 ?) ms
Bunch frequency 352.2 MHz
Duty cycle during the pulse 62 (5/8)
rms transverse emittances 0.4 p mm mrad
Longitudinal rms emittance 0.3 p deg MeV
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SPL PDAC 2/3

• SPL main goals
• increase the performance of the CERN high energy
  accelerators (PS, SPS LHC)
• address the needs of future experiments with
  neutrinos and radio-active ion beams

The present RD programme concentrates on
low-energy (Linac4) items, wherever possible in
collaboration with other laboratories.
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SPL PDAC 3/3
SPL (CDR2) PDAC characteristics

• Extrapolation from PDAC based on the SPL CDR-1

Mean beam power 4 MW
Kinetic energy 3.5 GeV
Pulse repetition rate 50 Hz
Pulse duration 1.66 ms
RF frequency 44.02 MHz
Number of bunches (buckets) 68 (73)
Number of protons per pulse (per bunch) 1.43 E14 (2.1 E12)
Number of turns for injection 345
rms normalized transverse emittances 50 p mm mrad
Longitudinal emittance 0.2 eVs
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Elements of comparison 1/2
Domain Issue of interest Question
Physics Fit to the requirements for the secondary beam Specifications
Physics Synergy with other physics needs Identification specs.
Physics Upgrade potential Identify
Physics Time to full performance / risk Estimate
Economics Global economical optimum at construction Cost as a function of energy rate at fixed beam power
Economics Minimal cost of exploitation (electricity, radioprotection, maintenance) Power efficiency Reliability Maintenance needs Radioprotection issues
Management Possibility of a staged implementation Study possibilities
Management Share the efforts with other teams working for other goals List of possibilities
Management Exploit/enrich available competence List
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Elements of comparison 2/2
Domain Issue of interest Linac Synchrotrons Synchrotrons
Physics Fit to the requirements for the secondary beam lt 8 GeV Shorter bunch distance Cycling rate (adjacent bursts ?) Higher energy Larger bunch distance Cycling rate 10 Hz gt15 GeV Higher energy Larger bunch distance Cycling rate 10 Hz gt15 GeV
Physics Synergy with other physics needs RIBs injector for HEP injector for HEP injector for HEP
Physics Upgrade potential Large (power, users) Small Small
Physics Time to full performance / risk Moderate/small ? ?
Economics Global economical optimum at construction To be studied To be studied To be studied
Economics Minimal cost of exploitation (electricity, radioprotection, maintenance) To be studied To be studied To be studied
Management Possibility of a staged implementation Yes (energy, power) Yes (energy, power) ?
Management Share the efforts with other teams working for other goals Yes (ADS, ILC, ) Yes (ADS, ILC, ) ?
Management Exploit/enrich available competence To be studied To be studied To be studied
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• To be continued

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• ANNEX

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Cost comparison
Cost
Energy
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SPL - CDR2 baseline

• RF
• 704 MHz bulk Niobium cavities
• 3 families of cavities beta 0.5,0.85,1.0
• gradients 15, 18, 30 MV/m
• 5, 6 and 7 cells per cavity

• Cold (2K) quadrupoles in the cryomodules,
  independently aligned from the cavities (to
  minimize cold/warm transitions and maximize real
  estate gradient).
• Cryomodules of maximum length (between 10 and 15
  m), containing n cavities and (n1) quadrupoles.
  Diagnostics, steering etc. between cryomodules.
• Length of the cavities limited by fabrication
  and handling considerations. Proposed number of
  cells per cavity is therefore 5, 6 and 7 for the
  three sections.
• 2 MW max power /coupler
• Standardisation of the design after 2 GeV

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HIP WG long term alternatives
lt-
Present accelerator Replacement accelerator Improvement INTEREST FOR INTEREST FOR INTEREST FOR INTEREST FOR
Present accelerator Replacement accelerator Improvement LHC upgrade n physics beyond CNGS RIB beyond ISOLDE Physics with k and m
Linac2 Linac4 50 160 MeV H H- 0 (if alone) 0 (if alone) 0 (if alone)
PSB 2.2 GeV RCS for HEP 1.4 2.2 GeV 10 250 kW 0 (if alone) 0 (if alone)
PSB 2.2 GeV/mMW RCS 1.4 2.2 GeV 0.01 4 MW (super-beam, b-beam ?, n factory) (too short beam pulse) 0 (if alone)
PSB 2.2 GeV/50 Hz SPL 1.4 2.2 GeV 0.01 4 MW (super-beam, b-beam, n factory) 0 (if alone)
PS SC PS/ for HEP 26 50 GeV Intensity x 2 0 (if alone) 0
PS 5 Hz RCS/ 26 50 GeV 0.1 4 MW (n factory) 0
SPS 1 TeV SC SPS/ 0.45 1 TeV Intensity x 2 ? 0
with brightness x2
need new injector(s)