CAT Chat Minutes

March 12, 2001


Information and Follow-up Items

1. Who requested low emittance and what exactly will it do?

Reduction of the horizontal emittance by 50% will improve the overall beam brilliance by at least a factor of two. The increased brilliance will be of direct benefit to those groups using coherence and/or microfocused beams as it will result in a smaller horizontal source size and divergence. It will, in general, make life easier for anyone trying to horizontally focus the ID beam since the divergence will be reduced. If the coupling remains the same, the (good) match between the vertical opening angle of the undulator radiation and the monochromator Darwin width will be extended to higher energies than is currently available.

2.Is dry ice available here at the laboratory?

Dry ice is available in building 205, Chemical Technology. Contact your floor coordinator and he/she will obtain more information for you or arrange for delivery.


User Information

During the past week, a couple of faults occurred related to the real-time feedback system and storage ring power supplies. Overall, availability is 96.7% and mean time between failures has increased to 26.2 hours.

A 48-hour machine studies period will begin Monday, March 12 at 0800 hours followed by two weeks of top-up.

The FY2001 Long Range Operations Schedule has been updated, adding the months of August and September. The SOM periods for the month of September are as follows:

  Beginning September 12 for ~ one week - low emittance (~ 4 nm-rad and coupling of ~1%) using 21 triplets replacing the 21 singlets

  Beginning September 18 through the end of the run - hybrid fill with top-up

During the upcoming runs, machine studies will be scheduled for the users to preview the low emittance operation.