Minutes of the June 15, 2007 Tevatron Department Meeting * Weekly Operations Summary (Dan Bollinger) - The Tevatron delivered 36 pb^-1 to the experiments this week. There were 8 HEP stores with initial luminosities between 132 and 245 ub^-1/sec. All were terminated intentionally except for store 5485 (aborted after only 2.5 hours due to the A0 yard breaker tripping off) and store 5492 (quench at E1 due to C:BQ9 low-beta quad current jumping around). The 2nd order chromaticity corrections have been implemented for HEP stores; evaluation of the benefit is ongoing. Making vertical angle bumps across B0 early in the squeeze has reduced losses their considerably. We have noticed peculiar shot-to-shot variation in the pbar injection closure that is contributing to larger pbar emittances; perhaps there is a misbehaving component in the transfer line? There have been several more pbar longitudinal instabilities soon after collisions; investigation continues. * Evaluating the Proton Tune Adjustment Script (Jerry Annala) - Jerry implemented an ACL script that adjusts the HEP (low-beta) proton tunes based on the Recycler pbar intensity after injecting protons. The goal is to reduce the shot-to-shot tune differences due to differing head-on beam-beam tune shift from the differing pbar intensities. The script takes the place of our manual changes usually made before the previous store ends. The script changes the low-beta slot using Ron's HEP tune mult spreadsheet entries. The script has maintained the initial proton tunes to within 0.001 over a range of ~1500E9 pbars and the lifetimes are more consistent. It's doing a decent job now. Possible improvements include using the pbar intensity actually reaching low-beta in the Tev, account for different emittances, and implement pbar tune changes based on the injected proton intensity. * P1/A1 Transfer Line Matching with IPM - Andreas was home sleeping since he got more study time over the owl shift, so there are no slides. He was able to eliminate the vertical proton beam size oscillations at injection by changing the Q701 and Q711 quads in the P1 line. The changes were implemented for the subsequent HEP shot, but no significant emittance reduction was observed. More time is needed to look at the horizontal plane. * Pbar Helix Measurements (Alex Valishev) - Alex reported on measurements he made on the "simulated" pbar collision helix using dipoles. The coupling is rather large ~0.01; improvements could be made with the SQD0 circuit at the expense of the coupling on the proton helix. He will investigate using the S7 coupling feeddown circuits instead. The chromaticities on both helices are now nearly identical: ~8 horz and ~10 vert; we can probably reduce the vertical chromaticity by 2-3 units. * New BLM Status Electronics (Dean Still) - Dean reported that there had been progress on the new BLM electronics being tested in A1. The electrical noise is still present, but software filtering in the front-end reduces it somewhat. There has been good progress on testing the software and correcting bugs. However, the system is not ready for operations. Work will continue on both hardware and software; we'll reevaluate in 1 month. We will pursue implementing the new electronics in the A4 house as an additional real-life commissioning. * Plan for Next Week - Deliver plenty of luminosity to CDF and D0 - IPM studies (Andreas, shot-setup and/or proton-only) - Complete implementation of second order chromaticity sextupoles. (Including proton-only and pbar-only (!) for collision helix closure) - TEL-1 studies (Seva, during HEP stores) - Try E48 bumper as abort gap cleaner (Steimel, Bruce, Elmie, proton-only)