ILC Target Vault Fluka Calculations

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ILC Target Vault Fluka Calculations

• Vinod Bharadwaj
• SLAC

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Questions

• Incoming energy is 280 kW for a conventional
  source and 220 kW for a undulator-based source
• Where does this energy go
• How much into the L-band, vault air, vault ..
• Can we use a superconducting Adiabatic Matching
  Device

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Copper cavity
Iron dump
Drive Beam
Aluminium solenoid
Boron shield
Tungsten shield
Tungsten or titanium target
50 cm
2.5 cm
50 cm
90 cm
Iron pre-beam dump 50cmX50cmX90cm
50 cm
200 cm
Iron inner Outer beam dumps CYLINDRICAL GEOMETRY
Beam pipe surrounded by 1 cm copper pipe (4
sections) 9cm W, 5 cm B, 5 cmW, 5cm B, 5cm W, 5cm
B, 5cm W, 5cm B CYLINDRICAL GEOMETRY
Target disk 1.2cm W or 1.42cm Ti
TARGET STATION (surrounded by 3 m thick concrete
vault at /- 7 m in x,y,z)
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Target Station Layout

• Target disk 1 m in diameter, 1.2 cm of W (4 rl)
  or 1.42 cm of Ti (.4rl)
• Prebeam dump is an iron box 50 cm x 50 cm x 90cm
  (along beam axis)
• Inner dump 5 cm iron cylinder, 50 cm long, 2
  meters from target
• Outer dump 1 m iron cylinder, 50 cm long, 2
  meters from target (minus the inner dump)
• Cavity is 1 cm thick copper pipe 2 meters long
  in between the target and inner/outer dumps
• Shield is alternating pipes of W and B, 5 cm
  thick except the first W layer which is 9 cm
  thick. Shield goes from 3.5 to 47.5 cm in radius
  and is 2 m long
• Solenoid is 2.5 cm thick Al pipe 2 meters long

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FLUKA RUNS

• Conventional 6.2 GeV electrons, 280kW beam
  power, 4 rl W target
• Conventional 6.2 GeV electrons, 280kW beam
  power, 4 rl W target, 2.5 tesla magnetic field
  between target and beam dump and inside solenoid
• Conventional 6.2 GeV electrons, 280kW beam
  power, 4 rl W target, 2.5 tesla magnetic field
  between target and beam dump and inside solenoid
  and 5 cm thick L-band pipe
• Undulator 2-10 MeV photons, flat distribution,
  220 kW beam power, 0.4 rl Ti target
• Undulator 50 MeV photons, 220 kW beam power,
  0.4 rl Ti target
• Undulator 2-10 MeV photons, flat distribution,
  220 kW beam power, 0.4 rl Ti target, solid
  tungsten shield

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Conventional 6.2 GeV electrons, 280kW beam
power, 4 rl W target
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Conventional 6.2 GeV electrons, 280kW beam
power, 4 rl W target, 2.5 tesla magnetic field
between target and beam dump and inside solenoid
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Conventional 6.2 GeV electrons, 280kW beam
power, 4 rl W target, 2.5 tesla magnetic field
between target and beam dump and inside solenoid
and 5 cm thick L-band pipe
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Undulator 2-10 MeV photons, flat distribution,
220 kW beam power, 0.4 rl Ti target
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Undulator 50 MeV photons, 220 kW beam power,
0.4 rl Ti target
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Undulator 2-10 MeV photons, flat distribution,
220 kW beam power, 0.4 rl Ti target, solid
tungsten shield
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Undulator 2-10 MeV photons, flat distribution,
220 kW beam power, 0.4 rl Ti target, closer
pre-beam shield
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COMMENTS

• At the gross level calculations make sense
• Undulator based positron production is more
  forward peaked and does not produce neutrons
• Solenoid can be shielded energy depositions
  are a fraction of a watt (use of an SC device may
  be feasible)
• Lot of energy deposited in the l-band, in the
  case of electrons this energy deposition is
  equivalent to the dump
• About 100-200 watts of energy makes it to the
  vault/vault air. Photons seem to deposit more at
  the vault than electrons. I think that it is
  because more energy flows backwards from the
  target and the pre-beam shield is not optimal.
  This needs to be understood.

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Follow-on Studies

• Fluka Calculations
• Better shield, cheaper shield, better layout,
  more realistic layout
• When can on transition to SC L-band
• Radiation damage
• What does deposited EM energy do
• Is deposited neutron energy different/worse
• Solenoid
• What field/field profile can be made with an SC
  device
• Field/field profile vs. positron capture
• L-band
• Reasonable gradient vs. duty factor vs. MWs
• Gradient vs. positron capture