Minutes of the October 23, 2009 Tevatron Department Meeting http://indico.fnal.gov/conferenceDisplay.py?confId=2865 * Weekly Operations Summary (Andreas Jansson) - The Tevatron delivered 54.3 pb-1 this week in 8 stores. 7 of these stores were ended intentionally, and one ended in a quench caused by a refrigerator failure. One store quenched before reaching low beta due to high losses in the B1 Low Beta Quads. Problems included several stores where the a longitudinal instability blew up either the Protons, the Pbars, or both. The Tevatron is still suffering from higher than normal transverse emittance of the Protons. Some work was done during the week to work on particle loss around D0 in the squeeze, and to move the transverse collision point at D0. It seems that there is some horizontal movement of the D1 Low Beta Quads responsible for this movement. * IPM studies (Andreas Jansson) - Several problems were identified and worked on this week related to getting reliable and consistent data from the IPM. There still seems to be a problem with the horizontal system delivering signals that are too small. The Acnet application now has plotting capabilities that should provide a useful look at the output. Also, the array data logger viewer is useful to look at tbt data from the IPM. There are still some things that need to be done in the near future: -Restore bad channel masks lost during the shutdown. -Redo the vacuum tests -Transverse scans to make sure the beam is in a functioning portion of the instrument. -Systematic timing scans * PBJ and the IPM (CY Tan) - The goals are to 1) use the IPM as a feedback mechanism to regulate the amount of Pbar Jacking used, and 2) monitor the health of the PBJ system. At the present time, only the vertical system is working well enough to use. The IPM has measured the Pbar emittance growth rate to be about .4p-mm-mrad/min where the expected rate would be nearly twice that measured. Some stores had much more noise on the signal than others and the stores with “good” data seemed to have a dual band of values. The error on the slope of the sigmas was between 10% and 35% leading to a 20% to 70% error in the emittance growth rate measurement. As of right now, the instrument is not yet able to be used as feedback for the PBJ, but probably can indicate the health of the PBJ system to some level. * Check of the RF systems (John Reid) - Several things have been looked at in the Tevatron RF system recently as a result of the frequent longitudinal instabilities. A couple minor things that were found and fixed involved cable terminations on the output of the raw resistive wall monitor pickup, and of the longitudinal damper drive. Outputs of the longitudinal damper, and the T:PGPN signal look normal. It was found that some of the RF cavities did have 311 MHz mode lines that line up with other cavities. It had been since about 2002 since these measurements were made. Before store 7286, the temperature of TRF1 cavity was changed by about 1 degree to move its 311 MHz mode lines. The lines for TRF 6 and 7 will probably also be separated in this way. The RF department will be considering development of a hardware damper for this mode that can be installed in the transmission line. * Plan for next week - Deliver Luminosity - Reduce the emittance growth of the Protons - Eliminate the longitudinal instabilities - Tune Mult calibrations - Separation scans - TEL 2 studies (one or two EOS plus Proton only studies) - IPM studies using 150 GeV coasting beam.