Static pressure in VD

Consider outgassing by: assuming outgassing rates of:

(mbar • l • s-1 • cm-2)

? 11 m2 Kapton (signal wires, pumped 40 hours) 10-7 H2O

? 2.3 m2 Al housing (per half) 10-10 H2

? 1.5 m2 bellows (per half) 10-9 H2

? 8 m2 SS vessel 10-10 H2

Pumps in detector volume: ? 140 l/s (per half) H2O

Pumps in tank: ? 4000 l/s H2

Bypass tube: 200 mm ? 4 mm pumped in the middle.

Calculate using a static flow model.

Result: 1•10-4 mbar in detector volume

1•10-8 mbar in VD tank

2•10-8 mbar • l • s-1 from det. vol. to VD tank