BaBar drift chamber aging study

نویسندگان

  • Changguo Lu
  • Joseph Henry
چکیده

In order to obtain a reliable estimate of the lifetime of the BaBar drift chamber, a dedicated aging test chamber has been constructed. The working gas mixture is Helium/Isobutane (80/20). After accumulating up to 0.11C/cm charge dose the anode wire showed no appreciable signs of aging, but the field wires showed a small Malter effect. At 0.2C/cm the gas gain dropped B6–9% and the Malter effect reaches a more serious level. By adding B4000ppm of water vapor into the gas mixture the Malter effect was virtually eliminated. Thereafter up to 0.31C/cm the anode wire aging showed no further degradation. r 2003 Elsevier B.V. All rights reserved.

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تاریخ انتشار 2004