Paper  Title  Page 

MOPPD016  Status of Proofofprinciple Experiment for Coherent Electron Cooling  400 


Funding: US DOE Office of Science, DEFC0207ER41499, DEFG0208ER85182; NERSC DOE contract No. DEAC0205CH11231. Coherent electron cooling (CEC) has a potential to significantly boost luminosity of highenergy, highintensity hadron colliders. To verify the concept we conduct proofoftheprinciple experiment at RHIC. In this paper, we describe the current experimental setup to be installed into 2 o’clock RHIC interaction regions. We present current design, status of equipment acquisition and estimates for the expected beam parameters. 

MOPPC090  Coupling Modulator Simulations into an FEL Amplifier for Coherent Electron Cooling  346 


Funding: Work supported by the US DOE Office of Science, Office of Nuclear Physics under grant numbers DEFG0208ER85182 and DESC0000835. Nextgeneration ion colliders will require effective cooling of highenergy hadron beams. Coherent electron cooling (CeC) can in principle cool relativistic hadron beams on ordersofmagnitude shorter time scales than other techniques*. Particleincell (PIC) simulations of a CeC modulator with the parallel VORPAL framework generate macroparticle distributions with subtle but important phase space correlations. To couple these macroparticles into a 3D simulation code for the freeelectron laser (FEL) amplifier, while retaining all details of the 6D phase space coordinates, we implemented an alternative approach based on particleclone pairs**. Our approach allows for selfconsistent treatment of shot noise and spontaneous radiation, with no need for quietstart initialization of the FEL macroparticles' ponderomotive phase. We present results of comparing fully 3D amplifier modeling based on the particleclone approach vs GENESIS simulations where distribution of bunching parameter was used as input. We also discuss enabling direct coupling of the VORPAL deltaf simulation output into 3D distributions of particleclone pairs. * V.N. Litvinenko and Y.S. Derbenev, Phys. Rev. Lett. 102, 114801 (2009). ** V.N. Litvinenko, "Macroparticle FEL model with selfconsistent spontaneous radiation," unpublished (2002). 

TUPPP093  General Results on the Nature of FEL Amplification  1804 


Freeelectron lasers are increasingly important tools for the material and biological sciences, and although numerical and analytical theory is extensive, a fundamental question about the nature of the FEL growing modes has remained unanswered. In this proceeding, we present results of a topological nature concerning the number of amplifying solutions to the 1dimensional FEL equations as related to the energy distribution of the electron bunches.  
WEPPR012  Simulating HighIntensity Proton Beams in Nonlinear Lattices with PyORBIT  2961 


Highintensity proton linacs and storage rings are essential for a) stateoftheart neutron source user facilities, b) extending the highenergy physics intensity frontier, c) as a driver to generate pions for a future neutrino factory or muon collider, and d) for transmutation of radioactive waste and associated energy production. For example, Project X at Fermilab will deliver MW proton beams at energies ranging from 3 to 120 GeV. Nonlinear magnetic lattices with large tune spreads and with integrable*, nearly integrable** and chaotic* dynamics have been proposed to maximize dynamic aperture and minimize particle loss. We present PyORBIT*** simulations of proton dynamics in such lattices, including the effects of transverse space charge.
* V. Danilov and S. Nagaitsev, PR STAB 13 084002 (2010) ** K. Sonnad and J. Cary, Phys. Rev. E 69 056501 (2004) *** A. Shishlo, J. Holmes and T. Gorlov, From Proceedings of IPAC '09 351354 

THYB02  Influence of Electron Beam Parameters on Coherent Electron Cooling  3213 


Coherent electron cooling (CeC) is promising to revolutionize the cooling of high energy hadron beams. The intricate dynamics of the CeC depends both on the local density and energy distribution of the beam. This talk should present a rigorous analytical model of the 3D processes (including diffraction) in the modulator and the FEL and describe how the theory is applied to electron beams with inhomogeneous longitudinal density and energy distributions in the process of CeC. The SPC would like you to describe the influence of electron beam energy and current variations along the bunch length.  
Slides THYB02 [0.878 MB]  