Observation of Instabilities of Coherent Transverse Ocillations in the Fermilab Booster

The Fermilab Booster - built more than 40 years ago - operates well above the design proton beam intensity of 4 · 1012 ppp. Still, the Fermilab neutrino experiments call for even higher intensity exceeding 5.5 · 1012 ppp. A multitude of intensity related effects must be overcome in order to meet this goal including suppression of coherent dipole instabilities of transverse oscillations which manifest themselves as a sudden drop in the beam current. In this report we present the results of observation of these instabilities at different tune, coupling and chromaticity settings and discuss possible cures.