Status of the AMS02 Superconducting Magnet

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Status of the AMS-02 Superconducting Magnet

• Steve Harrison
• Space Cryomagnetics

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• The magnet is complete and ready to prepare for
  testing.

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• The test facility for the magnet has been
  designed. Manufacture is being discussed with
  two firms in China.

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Why is it important to test the magnet?

• By testing the magnet before assembly into the
  flight cryostat we can
• Correct any faults without affecting the project
  schedule
• Complete much of the testing and training in
  parallel with other parts of the project.
• In this way we will save large amounts of time
  and money, and greatly reduce the technical risk.

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• The helium fill port is required to allow the
  helium vessel to be filled at pressures below
  atmospheric without air ingress.

The fill port is anchored to the vacuum vessel.
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• The bayonet can be inserted and withdrawn under
  vacuum.

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• All that flies is a small section of pipework
  outside the vacuum vessel, sealed with a vacuum
  valve.

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• The fill port mounted on the side of the helium
  vessel leak tester with an alignment jig.

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• Transfer line insertion device.

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• The long bellows allows the cryogenic bayonet to
  be withdrawn without letting air into the helium.

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• AMS requires a persistent switch for stable,
  long-endurance operation.

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• At the AMS TIM in July 2005 we described the
  development of a new class of persistent switch
  for operation at 1.8 K.

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• After successful testing of an engineering model
  switch, a qualification model has been
  constructed.

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• This was mounted in a vibration-proof cryostat

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• and vibrated to the levels required in the
  Structural Verification Plan.

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• The QM switch was tested in background fields up
  to 0.8 T at 1.8 K and 500 A. All specifications
  were met before and after vibration, and there
  was no degradation in the performance.

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• With Russian funding, about one half of the
  components of the straps have been ordered.

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• Testing of the prototype current leads and the EM
  thermo-mechanical pump has been completed.

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• We have been lent a glass cryostat by CERN which
  will allow us to carry out the required
  development of liquid acquisition devices.

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• Successful testing of the persistent switch and
  current leads is a great success.
• With the glass cryostat from CERN, the final
  stage of cryogenic component testing can begin.
• With the funding from Russia, procurement of the
  last major pieces of hardware can be undertaken.

• With the assistance of the Chinese, we hope to
  start magnet testing soon.