Speaker
Maria Kuhn
Description
In 2012 emittance calculations from luminosity indicated that about 30 % potential peak performance was lost due to transverse emittance blow-up through the LHC cycle. The origin of the blow-up was only partially understood. The available emittance measurement systems gave inconsistent results. During Long Shutdown 1 the LHC transverse profile monitors underwent important upgrades to improve availability and measurement accuracy. Emittance measurements through the 2015 LHC cycle will be presented. Significant emittance blow-up is still apparent. The majority of the blow-up occurs during the injection plateau and beginning of the energy ramp. IBS is one of the main sources. IBS simulation results will be shown and compared to measurements. In addition strong vertical emittance growth was observed at 450 GeV. The status of the investigations to identify the source of the vertical growth will be given. A first estimate of transverse emittance blow-up of BCMS beams will also be presented.
