• T. Kikuchi, N. Harada, T. Sasaki
  Nagaoka University of Technology, Nagaoka, Niigata
• C. Buttapeng, Namprom. Namprom
  University of the Thai Chamber of Commerce, Bangkok
• K. Horioka
  TIT, Yokohama
• K. Takayama
  KEK, Ibaraki

The KEK digital accelerator (KEKDA), which is an injector-free induction synchrotron capable of accelerating any ions with their possible charge state, is under construction*. This machine is an interesting device as a driver to explore a Warm Dense Matter (WDM) state. The irradiation onto a target at a small focal spot (< a few mm) with a short pulse duration (< 100 nsec) is required to create an interesting WDM state. The target temperature based on an equation-of-state fitted from SESAME table data is estimated as a function of the focal spot size and the ion number per bunch. Final focusing of an ion beam bunch extracted from KEKDA is realized through a half mini-beta system. For this purpose, the beamline has been carefully designed. Beam parameters, such as Twiss parameter, and the guiding magnet parameters will be given together with the drawing of the beamline.

*T. Adachi et al., “Modification of the KEK PS-Booster as a Digital Accelerator”, in this conference.

• T. Kikuchi
  Nagaoka University of Technology, Nagaoka, Niigata
• K. Horioka
  TIT, Yokohama

Possible emittance growth due to a nonuniform particle distribution can be analyzed with a thermal equilibrium state in various space-charge potential beams. The possible emittance growth is given by a function of a space-charge tune depression and a nonlinear field energy factor. The nonlinear field energy factor, which is determined by nonuniformity of a charge distribution, is estimated in the thermal equilibrium distribution on a cross-section in a beam. The nonlinear field energy factor changes with space-charge potential for the thermal equilibrium distribution. It is expected that the possible emittance growth will be decreased effectively to consider in the thermal equilibrium condition.