CAT Chat Minutes

November 5, 2001


Information and Follow-up Items

Are xbpm's incorporated in orbit correction?

The vertical XBPMs in the bending magnet front-ends are being utilized for orbit correction. It is important that the first photon shutter, PS1, remain open for both XBPMs to be available. If it closes, an error can be introduced due to the missing signals. The floor coordinators are aware of this situation and will continue to correct it.

User noticed on the schedule we now have periods with 16 hours of studies. Why was this done?

The higher amount of top-up operation has an increased impact in critical areas such as injector system maintenance and studies, as well as control room operator training. We felt the additional time was needed to provide this time during the longer periods of top-up. We will continue to evaluate the needs as we gain experience with top-up operation.

We have had trouble handling the increased heat load on our monochromator during low emittance operation. Our LN2 pump failed and was replaced by a spare from APS. This may have been the reason in our heat handling capability. Thank you for your support. If that is not the reason, how will we be able to run with the higher heat load?

If you still experience problems, even with the new LN2 pump, please call us and we will investigate the situation further. The low emittance operation should have minimal impact on your optics.

Some users, who were not current in their training, were able to access the facility. What is the policy of deactivating badges when training lapses?

We will check on this situation. Normally, badges remain activated up to two years or until GERT expires at which time the badges are deactivated. A user training history database is now accessible to all CATs and will provide the capability to check on non-resident users training before beamtime begins. Jeff Alicz (2-9252) will be meeting with CAT personnel for software training in the near future.


User Operations

CY Yao reviewed the operational start-up for run 2001-4. The statistics are: beam availability was 97.5% and the MTBF was 30.8 hours. Four faults had occurred leading to a total downtime of 3.13 hours. The trips were mostly rf related. We are still investigating the reasons for the lower than normal lifetime. In addition, vertical rms beam motion has doubled and the cause is unknown. Increased horizontal motion is also present and the causes have been isolated to construction activities in the LOM 436 parking lot and a noisy real-time feedback corrector, which has been replaced.

An 8-hour machine studies period will occur on Tuesday, November 6 beginning at 1600 hours. Operations will begin at 0800 with low emittance lattice in top up mode.