Log entry time 17:37:05 on September 16, 2009

Entry number 289981

Run Plan

1. When beam comes back tonight, do our beam diagnostics to make sure that everything is good (the optimal values for the raster, beam position, beam current, lumi RMS, and detector asymmetry RMS are on the whiteboard).
• With an empty target, do harp scans, which are done by MCC on request.
• Still with an empty target, do spot++ at 40 muA. Change the prescale factor PS8 to 1 and PS1 and 2 to 99999 to do spot++.
• Make sure that the raster is on!! Check that it is at the correct size.
• After ensuring that the raster is on, put in the hydrogen target and start taking production data.


2. Take production data! Watch the lumi widths to see if anything changes. Please check the histograms on the online data monitor with the reference ones on the shift how-to page (http://hallaweb.jlab.org/experiment/HAPPEX/opmanual/opmanual.html#HPXStartingonlineanalysis).


3. Take Compton data! You will need to start a new Compton run every two hours. The CODA screen to start and stop the Compton runs is in the back room.
• If the background rates get too high, the Compton HV will trip off and you won't be able to take data. If you cannot keep it going, page Megan Friend (584-0038), and if you cannot get her, page Alexandre Camsonne (584-5064).


4. Change the half-wave plate state when we get to 1M good pairs. Follow the instructions for doing this and running the flipper script here: http://hallaweb.jlab.org/experiment/HAPPEX/opmanual/opmanual.html#ChangingHalfWavePlate


5. Run spot++ every couple of hours and log it. Change the prescale factor PS8 to 1 and PS1 and 2 to 99999.


6. When we go back to production and things are somewhat stable, if our lumi widths are up into the 1300-1500 range, go down to 95 or 90 muA and take data for at least 30 minutes so that we can study the target boiling. Don't go below 100 muA unless you see the lumi widths go up to this range at 100 muA.


7. We are planning to have a Moller measurement tomorrow (the time is still to be determined).


8. Q2 quenched earlier today, and Ed came in and asked that we keep an eye on it.


9. We are really behind in our data goals at this point. Please do not be shy about calling in the expert on something if it is holding things up.

Concerns

• Ed reminded us that the tech on-call tonight is Todd Ewing.
• Scot Spiegel would like to make an access if we are going to be down for a while at a time when we can go to controlled access (in the daytime, 8am-5pm) to get some poly for shielding. If such a time presents itself, his extension is x5900, his cell is 757-536-5900, and his pager is 757-584-5900.
• If anyone must reset a magnet, they must make a halog entry stating which magnet on which arm, and what was wrong with it to require a reset. The word "tech" must appear in the subject line.
• Be sure that the prompt analysis is done for every run!
• The BTA program doesn't subtract any time to speak of for beam trips. Please manually subtract a full minute for each beam trip in the beam time accounting.
• Please write a detailed shift summary (including runs taken and any activities) and submit the BTA for each shift.
• Please make sure that the shift checklist is done once each shift.
• If you have to page or call someone for support, please do so from a counting house phone or it will be ignored!
• Keep a close eye on the lumi widths (RMS) as we take data.
• Please continue to take runs even if there is no beam. These data can be used to determine pedestals. Please label these runs as having no beam.