11/29/03 Beam Studies

Day (8:00 - 16:00)

- HallA Energy measurements. No beam to HallC.

Swing (16:00 - 24:00)

- Beam to Hall C at around 5pm.
- The first study done was to take a look at the analyzing power of the cathode. This seemed to show an analyzing power of ~10%.
- The shift crew began a test of the IA feedback code. This did not go as well as expected. The settings on the IOC channels that the ACC maintains cannot be changed from the HallC machines. Thus, the IA/PZT/RHWP voltages cannot be changed through the command line inputs "caput" and "caget". This seems to be due to the fact that the IOC gateway distinguished between machines on the ACC domain and those that are outside the ACC domain. The above commands do work from an ACC account. Thus, the feedback code was not able to talk to the appropriate IOC channels to control the IA/PZT voltages. This needs to be fixed, I believe, on the ACC side. Junho will be in contact with Joe Grames.
- This continued until around midnight.

Owl (00:00 - 08:00)

- The coil/Energy modulation checkout was done by Gary. First indications show that the above devices are working. A more complete analysis of the data he took is pending.
- The parity beam studies was done. Effectively the same program as yesterday (looking at damping/orthogonality change with beam transmission). Chao has taken some 30Hz FOPT data with the same conditions that I took the HallC PZT data, so we can compare the results. Analysis pending on the results.

Future studies

- The ACC group would like to know which fields on the beam spec. sheet they can check off. At the moment, it seems the specs on the maximum allowed noise at the helicity reversal frequency for the charge asymmetry and position differences are within spec. Tonight's study is to confirm the above statement by taking more data.
- The other spec that I may address is the maximum allowed average helicity correlation. Tonight, we will try a "slow feedback" to see if we can set the IA/PZT voltages by hand to see if the charge asymmetry and position differences can be reduced by those devices. Once we see a reduction, we will need to do a longer run demonstrate that it is stable over time (and make sure injector setup does not change over time).