User name paschke
Log entry time 22:05:18 on April19,2004
Entry number 118615
keyword=Energy spread acceptable (3e-5)
Energy spread now about 3e-5. 1C12 OTR screenshot is shown below.
(The OTR causes frequent beam trips but can, and should, be
inserted for a few minutes often to check the energy width.)
Changing the laser phase improved the energy spread, but it is clear
that another improvement was made in simply going to higher current
(above OTR reading was made around 70 uA). Apparently, the energy
spread was smallest near 70 uA, with a slight increase up near 90 uA
(the OTR width, in that current, went to 225 um. 240um is about
So no "deconvoluted" energy measurement was done here; the upper limit
established by the OTR was good enough. Arne hopes to revisit the
energy spread tomorrow during beam studies.
Also, work on SLI cross-calibration with the OTR has been delayed, at
least until beam studies tomorrow.