Beam Diagnostics

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Beam Diagnostics

• P.N. Ostroumov
• May 25, 2006

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What we need, minimum set on-line

• Current transformers (CT)
• RFQ exit, MEBT exit, RT exit , between the
  cryostats, end of the linac
• Beam phase pick-up necessary to control energy
  stability during the operation
• Can be combined with BPM (inter-cryo space)
• After RT section, between the cryostats and at
  the end of linac
• LLRF can extract info about the beam phase during
  the linac operation
• Initial tune-up of the cavity field and phase
• 360 deg slow phase shifter in the transmission
  line of every cavity, electronically controllable
• Use RT and SC cavities as a phase pick-up
• Requires 2 low power amplifiers that can be
  switched to all SC cavities for phase lock of the
  cavity and phase modulation
• LLRF capabilities to do it
• Beam profile wire scanners (or/and laser
  scanners)
• MEBT at least 1 scanner
• 4 scanners after RT cavities
• At least 2 scanners at the end of linac (can be
  part of the diagnostic station)
• Beam loss monitors about 20 distribute along
  the linac
• Inter-cryostat space should include
• CT
• BPM, includes phase pick-up

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Off-line (temporary installation)

• The temporary diagnostics station is desirable to
  use at the end of the following linac sections
• RFQMEBT
• RT section
• SSR1
• SSR2 - will be permanent place
• Diagnostics station includes (minimum set)
• 1 solenoid (or 3 quads, triplet)
• 2 steering magnets
• 2 BPMs, includes phase pick-up
• 3 profile monitors
• 2 current transformers
• Beam dump water cooled
• Energy degrader
• Faraday cup
• Fast Faraday cup
• CCD camera with the quartz foil
• Maximum set, extend for
• Emittance station slit-collector copy from
  SNS
• Bunch length custom design

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Mebt
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Beam box
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SSC MEBT
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SNS Diagnostics plate
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BPM (SNS)
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Bunch profile along the pulse (INR linac)
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Baseline - 05/15/06 long. envelope
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Modified, 05/25, long. envelope
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Baseline - 05/15/06 Trans. envelopes
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Modified, 05/25, Trans. envelopes
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No long. matching
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Lattice changes

• Add additional solenoid
• The first SSR-1 works as a buncher
• The second SSR1 is off
• Increase the filed level in all SSR1 by 10, the
  surface field is 31 MV/m
• Minimal impact on beam quality, more studies are
  required to insure that no additional emittance
  growth or beam lossses