Isochronous terahertz ring project at LNS, Tohoku University

Theoretical and experimental studies concerning isochronous storage rings, so far, suggest nonlinear effect resulted from higher order dispersion declines the “complete” isochronous system, and thus an ultimate equilibrated bunch length would be limited [1]. In addition, we have recently found that path-length deviation originated from the betatron motion is a much seriouse obstacle for the isochronous system and preservation of the bunch length [2]. However, it has been found out that a careful lattice design for the path-length cancellation seems to be very promissing, at least for a wavelength region of THz. A concept to preserve bunch form-factor by using quasi-dispersion-free arcs and proper phase advances of the betatron oscillation to cancel out the path length deviation is discussed.