• D.L. Bruhwiler, G.I. Bell, A.V. Sobol
  Tech-X, Boulder, Colorado
• I. Ben-Zvi, V. Litvinenko
  BNL, Upton, Long Island, New York
• Y.S. Derbenev
  Jefferson Lab, Newport News, Virginia

Novel electron-hadron collider concepts are a long-term priority for the international nuclear physics community. Effective beam cooling for intense, relativistic hadron beams will be necessary to obtain the orders-of-magnitude higher luminosities being proposed. Coherent electron cooling (CEC) [1] combines the best features of electron cooling and stochastic cooling, via free-electron laser technology [2], to offer the possibility of cooling high-energy hadron beams much faster. Many technical difficulties must be resolved via full-scale 3D simulations, before the CEC concept can be validated experimentally. The parallel VORPAL framework [3] is the ideal code for simulating the modulator and kicker regions, where the electron and hadron beams will co-propagate as in a conventional electron cooling section. We present initial VORPAL simulations of the electron density wake driven by single ions in the modulator section. Also, we present a plan for simulating the full modulator-amplifier-kicker dynamics, by through use of a loosely-coupled code suite including VORPAL, an FEL code and a beam dynamics code.

[1] Y.S. Derbenev, Proc. COOL07, 149 (2007).
[2] V.N. Litvinenko & Y.S. Derbenev, Proc. FEL07, 268 (2007).
[3] G.I. Bell et. al., J. Comp. Phys. (2008), in press.

• Y. Zhang, S.A. Bogacz, P. Chevtsov, J.R. Delayen, Y.S. Derbenev, M. Hutton, G.A. Krafft, R. Li, B.C. Yunn
  Jefferson Lab, Newport News, Virginia
• L. Merminga
  TRIUMF, Vancouver

A conceptual design of a ring-ring electron-ion collider based on CEBAF with a center-of-mass energy up to 90 GeV at luminosity up to 10³⁵ cm^-2s^-1 has been proposed at JLab to fulfil science requirements. Four interaction points on two crossing straight sections of Figure-8 shape rings are planed for collisions of both highly polarized electron and light ion beams. The Green field design of the ion complex including electron cooling and new way of organizing interacting regions are directly aimed at full exploitation of science program. Here, we summarize design progress including collider ring and interaction region optics with chromatic aberration compensation. Stacking of ion beams in an accumulator-cooler ring, beam-beam simulations and a faster kicker for the circulator electron cooler ring are also discussed.

Slides