• P. Thieberger, R. Bonati, G.F. Corbin, J.P. Cozzolino, A.K. Jain, G.T. McIntyre, M.G. Minty, C. Montag, J.F. Muratore, C. Schultheiss, S. Seberg, J.E. Tuozzolo
  BNL, Upton, Long Island, New York

We re­port on re­cent de­vel­op­ments for mit­i­gat­ing vi­bra­tions of the quadrupole mag­nets near the in­ter­ac­tion re­gions of the Rel­a­tivis­tic Heavy Ion Col­lid­er (RHIC). High pre­ci­sion ac­celerom­e­ters, geo­phones, and a laser vi­brom­e­ter were in­stalled around one of the two in­ter­ac­tion points to char­ac­ter­ize the fre­quen­cies of the me­chan­i­cal mo­tion. In ad­di­tion ac­tu­a­tors were mount­ed di­rect­ly on the quadrupole cryostats. Using as input the lo­cal­ly mea­sured mo­tion, dy­nam­ic damp­ing of the me­chan­i­cal vi­bra­tions has been demon­strat­ed. In this re­port we pre­sent these mea­sure­ments and mea­sure­ments of the beam re­sponse. Fu­ture op­tions for com­pen­sat­ing the vi­bra­tions are dis­cussed.