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