| Paper | Title | Page |
|---|---|---|
| THPLT095 | Nuclotron Extracted Beam Spill Control | 2715 |
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| The first experiments with the Nuclotron Beam Slow Extraction System (BES) were carried out in December 1999. After the BES commissioning, the development of the system was continued together with experiments on relativistic nuclear physics. To realize the constant-current-beam or the constant-time-length spill and to suppress the low frequency spill structure in the range up to several hundred hertz, a spill control subsystem was designed and put into operation. It consists of a feedback loop in parallel with a feed-forward control. In the feedback loop the extracted particle flux is measured with beam current monitor and is compared with the request flux. The resulting error signal is fed into a feedback controller. The controller is an analog unit in which integration, differentiation and gain can be adjusted separately. The output control signal is added to the extraction quadrupoles power supply pattern generated by the corresponding function generator. The beam spill control subsystem has been improved in stages since its commissioning in 2000. The beam spill duration of more than 10s and the beam spill uniformity of about 0.9 were achieved in recent Nuclotron runs. |