Notes from MI/RR Meeting - 5 March 2003
by Bruce Brown
Notes on 10 March 2003

Terry Anderson -- Recycler Vacuum Studies

The slides which Terry presented are available in the document database as part of these minutes. You can get the MSWord version if you like. You can pop up the pdf version as RR RGA Scans post 1_03.pdf. I will provide a little commentary. The plots show the uncalibrated (or at least not fully calibrated) output of Residual Gas Analyzers (RGAs) at indicated locations around the Recycler Ring. Many of them include comparisons with ion pumps on or off. Note that the bulk of the pumping for most gases (Hydrogen, Water, C0, C02) comes from the Titanium Sublimation Pumps (TSP's) such that the indications for those gases relate to very local effects. Gases not pumped by the TSP's include Methane, Ethane and Ar. Terry noted that very detailed calibration is required to provide accurate numbers on the ratio of the various gases, but that the general trend of the ratio of Hydrogen: Water: Methane: CO: Ar: CO2 are consistent and believable. The response to Ethane consists of the peak at 30 plus peaks at 29, 28, 27, 26 showing various numbers of detached hydrogens. In addition to the results from March 4, there are plots for some locations from January 2003 and during two shutdown times in 2002. Not included in the file is a beautiful new radial plot from the R56 application page showing the ion pumps (and soon the ion gauges) around the Recycler Ring. Summary plots for 'review season' are being prepared.

Other Discussion

Krish Gounder discussed the Recycler beam lifetime measurements since the January shutdown. Issues concerning the vacuum problems with the Recycler Flying Wire cans were discussed.