Scan Summary 

Step 1 
RGA Background Scan- 
*RGA volume isolated from chamber 
*RGA pumped by dedicated RGA turbo (pump speed < 10L/sec typical)
*Filament energized for minimum of 1 hour 
*Multiplier on 
*Stabilization observed via multiple "unsaved passes" 
*Take Scan

Step 2
Post-Bake Scan- 
*RGA volume valved-in to chamber 
*Chamber turbo (Main Turbo Pump, a.k.a "MTP") valved-out from chamber 
*RGA volume + chamber volume pumped only by RGA turbo 
*Pressure equilibration observed via multiple "unsaved passes" 
*Take Scan

Step3 
Calibration Scan-
*Valve arangement same as Step 2 
*Scanning stopped 
*Cal-Gas opened 
*Scanning resumed 10 mins after opening Cal-Gas 
*Pressure equilibration observed via multiple "unsaved passes" 
*Take Scan 
*Measure/adjust multiplier gain using same amu as used from Cal-Gas
*Close Cal-Gas 
*Isolate RGA volume from Chamber