Why the Present Shielding Plan was Abandoned.

1
Why the Present Shielding Plan was Abandoned.

• Radiation levels in the area of the collimators
  meant that it would require several crews to
  complete the shielding job.
• The awkwardness of location made it likely that
  the beam pipe or bellows would be damaged
  particularly if we had multiple crews trying to
  work quickly.
• The existing design did not allow for servicing
  of the motors, LVDTs, or vacuum flanges without
  unacceptable radiation exposure.
• There was no provision for the eventual removal
  of the system.
• Conclusion Remove collimators and do it right.

2
Conceptual Design of Collimator

• Integrate collimator and enough shielding for at
  least twice present Booster flux at 1 high field
  scraping into a movable system which can be
  assembled externally and installed quickly ( 1
  day)
• Design must include a clear plan to scale up to
  the full shielding (MiniBooNENuMI _at_ 2
  scraping).
• After extended operation at full flux
• There must be a reasonable method for servicing
  the motors and LVDTs.
• There must be a reasonable plan to remove the
  central collimation system (coffin) in the
  event of a catastrophic failure (e.g. vacuum
  leak).
• There must be a reasonable plan to remove the
  entire system in the event Santa brings us a new
  Booster.

3
Some Ground Rules

• No quick and dirty temporary solutions. What
  goes in, stays in.
• No partial designs. Nothing goes in until we have
  a clear plan for the whole system.

4
Some Desirable Features

• Use existing mover system, if reasonable.
• Use as much of the steel as reasonable.

5
Basic Design Choices

• Movable collimator inside a central coffin, all
  on rolling cart, around which full shielding
  could later be placed (Larrys 11th hour
  solution).
• Bed of steel placed down first, central
  collimation system placed on top ( how ?)
• Collimator fixed inside central shielding steel.
  Entire assembly is moved.

6
Goal

• Settle on broad features of design, and move
  ahead.
• Peter Kasper will be in charge of the project (I
  will cover for him until he gets back).
• Summer is soon than you think.