Paper  Title  Page 

WEPPR039  Nonlinear Lattice for SpaceCharge Dominated Beam Transport with Suppressed Emittance Growth  3021 


We present a feasible design for the implementation of a beam emittance growth suppressing lattice for spacecharge dominated beams. Our analysis is based on original derivations developed in *. We present a FODO focusing channel with quadrupole and duodecapole components which on average create the ﬁeld required to match the highbrightness beam with the structure. Matched beam exhibits smaller emittance growth than that in regular quadrupole focusing channel. Numerical results demonstrate the lattice’s performance in preventing halo formation of a nonuniform space charge dominated beam.
* Y. Batygin, Phys. Rev. E, 57, 5, p. 6020 (1998). 

THPPC090  Robust Control of a TwoInput TwoOutput (TITO) Multistate Cavity RF System ith Mismatched Uncertainty  3494 


A RF cavity is well modeled as a linear two input two output (TITO) system in the Inphase/Quadrature (IQ) coordinates and is both controllable and observable. Whether it is due to the beam loading or Lorentz force detuning of a superconducting cavity, a cavity frequency detuning can be modeled as a matched uncertainty. The cavity field of a TITO cavity system with a matched uncertainty is controlled by output feedback or state feedback, whose error bound is made arbitrary small. Because of the building cost of the RF system, the single RF source (single klystron)multicavity structure is sometimes used. This structure is described as a twoinput multipleoutput (TIMO) system. The control problem is not a simple extension of the single TITO system. Though the controllability and observability are preserved, the matched uncertainty of the TITO cavity system caused by cavity detuning becomes a mismatched uncertainty. The error bound of outputs is made arbitrary small by a control, only boundedness of the cavity fields of each TITO subsystem is guaranteed. In this paper, the properties of the TITO and the TIMO cavity RF systems are investigated.  