Studies of Cold Protection Diodes

  • Ruben Carcagno
  • John Zeigler

Abstract

The feasibility of a passive quench protection system for the Superconducting Supercollider (SSC) main ring magnets depends on the radiation resistance and reliability of the diodes used as current bypass elements. These diodes would be located inside the magnet cryostat, subjecting them to liquid helium temperature and a relatively high radiation flux. Experimental and theoretical efforts have identified a commercially available diode which appears to be capable of surviving the cryogenic temperature and radiation environment of the accelerator. High current IV measurements indicate that the usable lifetime of this diode, based on an estimate of the peak junction temperature during a quench pulse, is an order of magnitude greater then than the expected lifetime of the SSC itself. However, an unexpected relationship was discovered between the diode turn-on voltage at 5 K and the most recent reverse voltage or temperature excursion. This turn-on voltage as a function of radiation exposure appears to be erratic and indicates a need for further investigation.

Keywords

Carrier Lifetime Cryogenic Temperature Liquid Helium Temperature Junction Temperature Reverse Voltage 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer Science+Business Media New York 1990

Authors and Affiliations

  • Ruben Carcagno
    • 1
  • John Zeigler
    • 2
  1. 1.Superconducting Super Collider LaboratoryDallasUSA
  2. 2.Texas Accelerator CenterThe WoodlandsUSA

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