Measurement and simulation of space-charge dependent tune separation in fnal booster

In recent years, a number of space-charge studies have been performed in the FNAL Booster. The Booster is the lowest energy circular accelerator in the Fermilab chain of machines, with an injection energy of 400 MeV. Measurement and simulation of space charge coupling in the Booster will be presented. The coupling measurement was performed using a standard technique, albeit repeated for different injected beam intensities. The initial transverse tune separation was minimized (Qx=Qy=6.7), followed by a systematic skew quadrupole strength variation. Transverse beam oscillation frequencies were recorded while exciting the beam. These frequencies were recorded for a range of 1.0times10¹² to 3.5times10¹² particles. A linear increase in the measured tune separation with beam intensity was observed. For comparison, beam coupling was also simulated with the space-charge code Synergia. This code has successfully modeled the space-charge tune shift in the Booster, and compares favorably to other space charge codes and analytic results.