Vertical Emittance Reduction and Preservation at the Esrf Electron Storage Ring

In 2010 a campaign for the reduction and preservation of low vertical emittance at the ESRF electron storage ring was undertaken: values between 20 and 30 pm have been dramatically reduced to 3.5 pm, even during beam delivery. This improvement is the result of an increased measurement precision provided by the recently upgraded beam position monitoring system, a new correction algorithm, a larger number of correctors and two independent schemes for the automatic compensation of coupling induced by a few insertion devices whenever their gaps are moved by users during beam delivery. This paper summarizes the campaign’s milestones and the results updated to the first half of 2011.