Minutes: Kaon Collaboration Meeting, 11/30/00 at JLab

1. Pete Markowitz leads discussion of various electronics, beam, and detector issues:
1. Narrowing the coincidence gate
2. DAQ limits: 20% deadtime or 75 microamps and overall DAQ rate < 2Khz.
3. Gas Čerenkov in Hadron arm: won't need but still leave in the trigger.
4. Beam will be polarized. We will have very little sensitivity. Helicity information will be in the datastream.
5. Will need measurement of absolute beam energy for L/T separations
6. Pete is maintaining the web page (http://www.jlab.org/~markowit/)
7. Have four run coordinators lined up:
1. Nilanga Liyanage
2. Jörge Reinhold
3. Pete
4. Mauro Iodice
5. Need 2 more (Doug Higinbotham maybe)
2. Mauro Iodice make presentation and leads discussion re kinematics for the experiment
1. Goal: need a good data set with a large range in W, Q², and t in order to extract the Kaon form factor.
2. Presently scheduled for:
1. 6.618 GeV: 4 days
2. 3.395 GeV: 18 + 5 days
3. 4.232 GeV: 9 (12) days
3. Expect 75 microamps with 15cm LH2 target (present operational limit at 5.6 is 50 microamps)
4. Kinematical constraints:
1. 12.5° minimum angle
2. ~3.2 GeV/c on electron (right) arm
5. Discusses method(s) of form factor extraction:
1. Chew-Low extrapolation to t = M_K²
2. Presents table of Q² = 1.9, 2.35 (σ_L/σ_T separation kinematics)
3. Shows model dependence plots with assorted models (SLA, Reggae, Saclay-Lyon)
4. Need to measure σ_LT to constrain the models
5. Problem of "Model dependent analysis" discussed
6. Shows table of σ_LT interference kinematics (8 measurements at high energy, 2 at lower energy)
7. Need to coordinate well with Roy Holt and Haiyan Gao re smooth efficient interface between our experiments:
1. Target issues (He vs. D₂ and H₂)
8. Need for 1 extra day and fall back plans highlighted.
1. There are places where we can cut back 50% on statistics
2. At 3.395 GeV need 8.3 days but have 23 days scheduled. Pete will check to see if we can trade some of the 4-pass (3.395 GeV) for 5-pass (4.232 GeV). Would like 14 days at 4-pass and 18 days at 5-pass, instead of 23 and 9.
3. Nilanga Liyanage presents status of the optics data bases
1. Expect that at the start of running will have a full set of databases. Will only need to check offsets.
2. Recommended optics study is a 5 step δ-scan (requires about 1 shift)
3. During the experiment will need:
1. Surveys of both arms
2. BPM-Harp calibration
3. Fast feedback ON
4. Beam energy measurement
5. Run for 5 minutes at each new setting with the optics (multi-foil carbon) target in.
4. Nilanga will write up a plan for the commissioning time.
5. Re angular accuracy needed Pete says 0.6 mrad is plenty.
4. Lingyan Zhu reports on A₁ and A₂ performance studies (see Hall A group meeting minutes of 11/28/00 for details on A₁ and A₂.
1. A₂ analysis software is done but needs to be incorporated in the "official" ESPACE release. Pete will see that Ole gets the input from the right people. (BPM stuff too!)
2. Point of interest: Haiyan doesn't run He at 1 GeV
5. General things:
1. There is work to do in the Hall in early January. Could use about 6 people. Need a list of work to do during January maintenance
2. People:
1. From FIU: Pete and a thesis student + 3 other FIU people.
2. The others were less clear.
3. Discussed the possible need for a 4^th person on shift to analyze data. Early analysis is important. Won't be able to judge the quality of the data without analysis.
4. Need to develop a set of "standard" histograms. Probably should come out of Haiyan's experiment. We need a volunteer.
6. Next meeting will be in early January to review the run plan and status.