Notes - instrumentation/beam physics meeting - Nov 10, 2004

Topic: Proposal for damping low frequency orbit motions in the Tev
         - Wahid Ranjbar

 Notes:
        Vahid presented his proposal for a system to damp low
        frequency orbit motions in the Tevatron.  His talk is
        document 1447.

Comments/questioons from the people at the meeting:
            1) Is the system still needed given the new supports
               for the low beta quads at CDF?
            2) Does rapid cycling of the dipole correctors excite
               the other windings in the spool piece?
            3) what is the effect of slewing due to the band width
               of the current regulators for the power supply
               controllers?  This  might explain the phase differences
               that Vahid saw.
            4) The scheme assumes point sources of the disturbances
               (B0 and/or D0) and perfect knowledge lattices,
               hence perfect cancelation of the disturbance, and
               a perfect feed forward system. Since life isn't
               perfect, the system could easily be unstable.
            5) Special BPM electronics has been developed for a NUMI
               application that might be applicable here.  This would
               be particularly useful if it means not using legacy
               Tev BPM electronics.