BaBar drift chamber aging study

✍ Scribed by Changguo Lu

• Publisher: Elsevier Science
• Year: 2004
• Tongue: English
• Weight: 344 KB
• Volume: 518
• Category: Article
• ISSN: 0168-9002
• DOI: 10.1016/j.nima.2003.10.039

✦ Synopsis

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 0.11 C/cm charge dose the anode wire showed no appreciable signs of aging, but the field wires showed a small Malter effect. At 0.2 C/cm the gas gain dropped B6-9% and the Malter effect reaches a more serious level. By adding B4000 ppm of water vapor into the gas mixture the Malter effect was virtually eliminated. Thereafter up to 0.31 C/cm the anode wire aging showed no further degradation.