Minutes of the Tevatron Department Meeting Fri 05/24/02 1. Bruce Hanna is scheduled to be the Tevatron coordinator for 1 month starting June 1, 2002. 2. Bruce reported that a) we are leaning toward replacing C0 Lambertson magnets with MI magnets (in series with the Tev bus, some shunt required); b) larger aperture F0 BPM fabrication is in high gear; there are some concerns with the insulator for plate supports; c) the first sample of the "like F11" ferrite has shown no sign of an outgasing rate decrease after baking for 2-3 days. It's quite discouraging as we might be forced to remove the microwave absorbers. The second type of ferrite is under test. 3. Jerry on the Tev luminosity: a) 4 good stores (L around 17-19) and one bad store #1356 when we have blown up proton and (even more) pbar emittances at the ramp - that was a store with record p-intensity (7200e9 in 36 bunches); b) L-lifetime is still bad 9-11 hours (because he stopped to lower p-bar tunes - unclear?); c) bunch length blow-up are now regular at the beginning of the stores (early at 980 GeV). Sigma_s tends to grow from 2 to 2.6 ns rms. 4. Tanaji has analyzed pbar tune spectra measured by Tan and found complete disagreement with model predictions. Possible explanations (to be tested): a) H and V planes are switched; b) we do not understand where pbar tunes are without protons in the Tev; c) tune spread due to dP/P is large; needs to be reduced (either reduce chromaticity or by momentum shaving). Tan states that the spectra are quite reproducible, though the tune measurement error is unknown. 5. Vladimir and XL did get record proton intensity at low-beta (220e9/bunch) during p-only studies with 11 bunch coalescing in MI. Injection into the TEV took place with the TEL on which was cleaning out some 10% of the DC beam from MI. Initial transverse emittances were not that different from 7-bunch coalescing, but the high-intensity proton beam is subject to significant blow-up (+60% in H and V emittance) right after the ramp and few minutes later at 980 GeV. Behavior is very similar to what was observed in store #1356. If that is to be fixed (by increasing chromaticity) then 11 bunch coalescing to be tried for HEP store. 6. Mike Martens reported results of the start of the ramp tune-up: orbits are smoothed up to 200 GeV, chromaticities adjusted. 7. Yuri continued to perfect new-new 150 GeV helix that includes C0 position adjustment, prevention of fast vertical separation increase at the beginning of the ramp, and playing with horizontal separators to get more space at F0. While ramping, he observed crossing the tunes and proposed corresponding adjustment.