Notes from Main Injector/Recycler Group Meeting Monday 21 October 2002 Bruce C. Brown Gerry Jackson - Booster Longitudinal Emittance Studies Gerry's slides are available at http://www-ap.fnal.gov/~bcbrown/MtgNotes/GPJ_booster_02_10_21.pdf or http://beamdocs.fnal.gov/DocDB/0003/000385/001/GPJ_booster_02_10_21.pdf Data was presented which was taken with the Resistive Wall Monitor (RWM) of the Booster using a LeCroy digital scope with sampling at 4 G-samples/sec. Comparing bunch shapes near but before transition, the base width in nanoseconds is the same for beam with 2 turn injection and 12 turn injection (the bunch shape is different in a non-trivial way, however). This is big news since it eliminates many issues when considering the problems with poor longitudinal emittance at high intensities. After transition, there is a mode 0 (all bunches together) bunch length oscillation which has the same amplitude for 2 turn and 12 turn operation. The phase jump is done with an inverting amplifier so its magnitude is 'right' (acceleration before and after work and the phase is set by feedback so the jump is 'correct' if you don't want to have a deliberate offset to counter space-charge or other transition-specific problems. By the time you get to the turn before the beam is extracted, there are big problems with the phase of the bunches, showing both single bunch and perhaps coupled bunch effects. Studies will continue. Krish Gounder - RR Study Plans Ralph Pasquinelli will be doing further cooling studies. Then there will be an attempt to re-bunch the PBars and transfer them to the MI where we will try to accelerate them. After an 8-hour access on Tuesday, there will be an emphasis on proton studies. Effects of the MI on the RR will be a priority. Ming-Jen Yang reported that the RR TBT data acquisition from the new DDC (Digital Down Converter) BPM modules is now working. RMS ~ 0.07 mm. However, the system takes more than 5 seconds to get the data back so extraordinary measures are required to make the programs acquire the data. Shekhar Mishra - Plans Expect to make changes in the RR operation so that the MiniDip Ramp on Recycler $2D events is not required. We would like to make transfers this week in that mode.