Minutes from the Feb 13, 2009 Tevatron Dept Meeting http://indico.fnal.gov/conferenceDisplay.py?confId=2393 * Weekly Operations Summary (Bruce Hanna) - The Tevatron delivered 38.7 pb^-1 to the experiments over the past 7 days. The main rason for the lower luminosity was an unplanned power outage in the MCR Tuesday evening (failed transformer) that resulted in damage to 3 Tevatron electrical dump switches. (More on that below.) There have been 6 stores with initial luminosities betwen 217 and 321 ub^-1/s. We may have identified a contributing factor to the mysterious C2 quenches: the pbar sync-light mirror moving into the beam. The mirror starts moving after the Tevatron reaches flat-top, but it may be too close to the beam early in the squeeze thanks to the delay needed for "jacking" the pbars; there is also evidence of a higher gas load in the beam pipe that may be consistent with that hypothesis. The mirror motion has been delayed until after pbar "jacking" is complete. We have been making tune and chromaticity adjustments at flattop and during the squeeze to help improve proton lifetime - it seems lowering the vertical tune has helped the most. * Analysis of Dump Failures (Dan Wolff/Jerry Annala) - Dan gave a thorough description of the chain of events. (I will just report the highlights.) The MCR power outage caused the dump and fast-bypass loop controller to lose power. The dumps kick in as designed after ~60 ms, but noise on the dump loop cause many dumps to switch back off after ~0.1 s. After the QPMs try to switch the dumps back in, the dump switches had to dissipate a lot of power (~800 kW). The DC breakers (slow) start to open as intended. The IGBTs and IGCTs in the 3 solid-state dumps eventually fail and open up, putting their dumps into the circuit. The SCRs in the older dumps are OK. The damaged dumps in B3, C2, F3 are repaired/rebuilt. EE Support will work on modifications (both active and passive) to prevent this scenario again. (The failed transformer for the MCR has been replaced and is now operational.) * Status of BBQ (Chip Edstrom) - Chip showed that the BBQ can give good tune measurements during HEP stores. The proton channel needed an input pad for operation early in stores. The pbar channel suffers from lower pbar intensity later in stores, but additional filtering can help. Overall, the BBQ performs favorably compared to the 1.7 GHz Schottky. Still to be pursued: improving the pbar tune measurements, gating for bunch-by-bunch tune measurements, getting the VSA repaired, additional tweaks to improve operation. We also requested to make measurements at 150 GeV, up the ramp, and in the squeeze. * Plan for Upcoming Week - Get the Tevatron back up and delivering luminosity.