IPAC2012 - List of Authors (Hao, Y.)

Paper

Title

Page

Coupling Modulator Simulations into an FEL Amplifier for Coherent Electron Cooling

346

I.V. Pogorelov, G.I. Bell, D.L. Bruhwiler, B.T. Schwartz, S.D. Webb
Tech-X, Boulder, Colorado, USA
Y. Hao, V. Litvinenko, G. Wang
BNL, Upton, Long Island, New York, USA

Funding: Work supported by the US DOE Office of Science, Office of Nuclear Physics under grant numbers DE-FG02-08ER85182 and DE-SC0000835.
Next-generation ion colliders will require effective cooling of high-energy hadron beams. Coherent electron cooling (CeC) can in principle cool relativistic hadron beams on orders-of-magnitude shorter time scales than other techniques*. Particle-in-cell (PIC) simulations of a CeC modulator with the parallel VORPAL framework generate macro-particle distributions with subtle but important phase space correlations. To couple these macro-particles into a 3D simulation code for the free-electron laser (FEL) amplifier, while retaining all details of the 6D phase space coordinates, we implemented an alternative approach based on particle-clone pairs**. Our approach allows for self-consistent treatment of shot noise and spontaneous radiation, with no need for quiet-start initialization of the FEL macro-particles' ponderomotive phase. We present results of comparing fully 3D amplifier modeling based on the particle-clone approach vs GENESIS simulations where distribution of bunching parameter was used as input. We also discuss enabling direct coupling of the VORPAL delta-f simulation output into 3D distributions of particle-clone pairs.
* V.N. Litvinenko and Y.S. Derbenev, Phys. Rev. Lett. 102, 114801 (2009).
** V.N. Litvinenko, "Macro-particle FEL model with self-consistent spontaneous radiation," unpublished (2002).

MOPPD016

Status of Proof-of-principle Experiment for Coherent Electron Cooling

400

I. Pinayev, S.A. Belomestnykh, I. Ben-Zvi, J. Bengtsson, A. Elizarov, A.V. Fedotov, D.M. Gassner, Y. Hao, D. Kayran, V. Litvinenko, G.J. Mahler, W. Meng, T. Roser, B. Sheehy, R. Than, J.E. Tuozzolo, G. Wang, S.D. Webb, V. Yakimenko
BNL, Upton, Long Island, New York, USA
G.I. Bell, D.L. Bruhwiler, V.H. Ranjbar, B.T. Schwartz
Tech-X, Boulder, Colorado, USA
A. Hutton, G.A. Krafft, M. Poelker, R.A. Rimmer
JLAB, Newport News, Virginia, USA
M.A. Kholopov, P. Vobly
BINP SB RAS, Novosibirsk, Russia

Funding: US DOE Office of Science, DE-FC02-07ER41499, DE-FG02-08ER85182; NERSC DOE contract No. DE-AC02-05CH11231.
Coherent electron cooling (CEC) has a potential to significantly boost luminosity of high-energy, high-intensity hadron colliders. To verify the concept we conduct proof-of-the-principle 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.

MOPPD038

Simulation Study of Electron Response Amplification in Coherent Electron Cooling

448

Y. Hao, V. Litvinenko
BNL, Upton, Long Island, New York, USA

Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
In Coherent Electron Cooling (CEC), it is essential to study the amplification of electron response to a single ion in the FEL process, in order to proper align the electron beam and the ion beam in the kicker to maximize the cooling effect. In this paper, we use Genesis to simulate the amplified electron beam response of single ion in FEL amplification process, which acts as 'Green function' of the FEL amplifier.

TUPPP088

Bunch Compressor Design for Potential FEL Operation at eRHIC

1795

Y.C. Jing, Y. Hao, V. Litvinenko
BNL, Upton, Long Island, New York, USA

Electron-Relativistic Heavy Ion Collider (eRHIC) is an upgrade project for the current operation of RHIC. It will provide a high quality electron beam with energy recovery scheme to collide with ion beams. One may think of taking advantage of using this electron beam for FEL operation. Bunch compressor is a crucial component to compress the beam to high peak current for undulators and CSR effect needs to be taken care of to preserve the beam quality. In this paper, authors present a novel bunch compressor design with CSR suppression scheme for the potential FEL operation at eRHIC.

TUPPR083

Kink Instability Suppression with Stochastic Cooling Pickup and Kicker

2017

Y. Hao, M. Blaskiewicz, V. Litvinenko, V. Ptitsyn
BNL, Upton, Long Island, New York, USA

Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
The kink instability is one of the major beam dynamics issues of the linac-ring based electron ion collider. This head-tail type instability arises from the oscillation of the electron beam inside the opposing ion beam. It must be suppressed to achieve the desired luminosity. There are various ways to suppress the instability, such as tuning the chromaticity in the ion ring or by a dedicated feedback system of the electron beam position at IP, etc. However, each method has its own limitation. In this paper, we will discuss an alternative opportunity of suppressing the kink instability of the proposed eRHIC at BNL using the existing pickup-kicker system of the stochastic cooling system in RHIC.

THYB02

Influence of Electron Beam Parameters on Coherent Electron Cooling

3213

G. Wang, Y. Hao
BNL, Upton, Long Island, New York, USA
V. Litvinenko
Stony Brook University, Stony Brook, USA
S.D. Webb
Tech-X, Boulder, Colorado, USA

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]

THEPPB002

High-Fidelity 3D Modulator Simulations of Coherent Electron Cooling Systems

3231

G.I. Bell, D.L. Bruhwiler, I.V. Pogorelov, B.T. Schwartz
Tech-X, Boulder, Colorado, USA
Y. Hao, V. Litvinenko, G. Wang
BNL, Upton, Long Island, New York, USA

Funding: This work is supported by the US DOE Office of Science, Office of Nuclear Physics, grant numbers DE-SC0000835 and DE-FC02-07ER41499. Resources of NERSC were used under contract No. DE-AC02-05CH11231.
Next generation electron-hadron colliders will require effective cooling of high-energy, high-intensity hadron beams. Coherent electron cooling (CeC) can in principle cool relativistic hadron beams on orders-of-magnitude shorter time scales than other techniques*. The parallel VORPAL framework is used for 3D delta-f PIC simulations of anisotropic Debye shielding in a full longitudinal slice of the co-propagating electron beam, choosing parameters relevant to the proof-of-principle experiment under development at BNL. The transverse density conforms to an exponential Vlasov equilibrium for Gaussian velocities, with no longitudinal density variation. Comparison with 1D1V Vlasov/Poisson simulations shows good agreement in 1D. Parallel 3D simulations at NERSC show 3D effects for ions moving longitudinally and transversely. Simulation results are compared with the constant-density theory of Wang and Blaskiewicz**.
* V.N. Litvinenko and Y.S. Derbenev, Phys. Rev. Lett. 10², 114801 (2009).
** Wang and Blaskiewicz, Phys Rev E 78, 026413 (2008).

Paper	Title	Page
MOPPC090	Coupling Modulator Simulations into an FEL Amplifier for Coherent Electron Cooling	346
	I.V. Pogorelov, G.I. Bell, D.L. Bruhwiler, B.T. Schwartz, S.D. Webb Tech-X, Boulder, Colorado, USA Y. Hao, V. Litvinenko, G. Wang BNL, Upton, Long Island, New York, USA
	Funding: Work supported by the US DOE Office of Science, Office of Nuclear Physics under grant numbers DE-FG02-08ER85182 and DE-SC0000835. Next-generation ion colliders will require effective cooling of high-energy hadron beams. Coherent electron cooling (CeC) can in principle cool relativistic hadron beams on orders-of-magnitude shorter time scales than other techniques. Particle-in-cell (PIC) simulations of a CeC modulator with the parallel VORPAL framework generate macro-particle distributions with subtle but important phase space correlations. To couple these macro-particles into a 3D simulation code for the free-electron laser (FEL) amplifier, while retaining all details of the 6D phase space coordinates, we implemented an alternative approach based on particle-clone pairs. Our approach allows for self-consistent treatment of shot noise and spontaneous radiation, with no need for quiet-start initialization of the FEL macro-particles' ponderomotive phase. We present results of comparing fully 3D amplifier modeling based on the particle-clone approach vs GENESIS simulations where distribution of bunching parameter was used as input. We also discuss enabling direct coupling of the VORPAL delta-f simulation output into 3D distributions of particle-clone pairs. V.N. Litvinenko and Y.S. Derbenev, Phys. Rev. Lett. 102, 114801 (2009). ** V.N. Litvinenko, "Macro-particle FEL model with self-consistent spontaneous radiation," unpublished (2002).

MOPPD016	Status of Proof-of-principle Experiment for Coherent Electron Cooling	400
	I. Pinayev, S.A. Belomestnykh, I. Ben-Zvi, J. Bengtsson, A. Elizarov, A.V. Fedotov, D.M. Gassner, Y. Hao, D. Kayran, V. Litvinenko, G.J. Mahler, W. Meng, T. Roser, B. Sheehy, R. Than, J.E. Tuozzolo, G. Wang, S.D. Webb, V. Yakimenko BNL, Upton, Long Island, New York, USA G.I. Bell, D.L. Bruhwiler, V.H. Ranjbar, B.T. Schwartz Tech-X, Boulder, Colorado, USA A. Hutton, G.A. Krafft, M. Poelker, R.A. Rimmer JLAB, Newport News, Virginia, USA M.A. Kholopov, P. Vobly BINP SB RAS, Novosibirsk, Russia
	Funding: US DOE Office of Science, DE-FC02-07ER41499, DE-FG02-08ER85182; NERSC DOE contract No. DE-AC02-05CH11231. Coherent electron cooling (CEC) has a potential to significantly boost luminosity of high-energy, high-intensity hadron colliders. To verify the concept we conduct proof-of-the-principle 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.

MOPPD038	Simulation Study of Electron Response Amplification in Coherent Electron Cooling	448
	Y. Hao, V. Litvinenko BNL, Upton, Long Island, New York, USA
	Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy. In Coherent Electron Cooling (CEC), it is essential to study the amplification of electron response to a single ion in the FEL process, in order to proper align the electron beam and the ion beam in the kicker to maximize the cooling effect. In this paper, we use Genesis to simulate the amplified electron beam response of single ion in FEL amplification process, which acts as 'Green function' of the FEL amplifier.

TUPPP088	Bunch Compressor Design for Potential FEL Operation at eRHIC	1795
	Y.C. Jing, Y. Hao, V. Litvinenko BNL, Upton, Long Island, New York, USA
	Electron-Relativistic Heavy Ion Collider (eRHIC) is an upgrade project for the current operation of RHIC. It will provide a high quality electron beam with energy recovery scheme to collide with ion beams. One may think of taking advantage of using this electron beam for FEL operation. Bunch compressor is a crucial component to compress the beam to high peak current for undulators and CSR effect needs to be taken care of to preserve the beam quality. In this paper, authors present a novel bunch compressor design with CSR suppression scheme for the potential FEL operation at eRHIC.

TUPPR083	Kink Instability Suppression with Stochastic Cooling Pickup and Kicker	2017
	Y. Hao, M. Blaskiewicz, V. Litvinenko, V. Ptitsyn BNL, Upton, Long Island, New York, USA
	Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy. The kink instability is one of the major beam dynamics issues of the linac-ring based electron ion collider. This head-tail type instability arises from the oscillation of the electron beam inside the opposing ion beam. It must be suppressed to achieve the desired luminosity. There are various ways to suppress the instability, such as tuning the chromaticity in the ion ring or by a dedicated feedback system of the electron beam position at IP, etc. However, each method has its own limitation. In this paper, we will discuss an alternative opportunity of suppressing the kink instability of the proposed eRHIC at BNL using the existing pickup-kicker system of the stochastic cooling system in RHIC.

THYB02	Influence of Electron Beam Parameters on Coherent Electron Cooling	3213
	G. Wang, Y. Hao BNL, Upton, Long Island, New York, USA V. Litvinenko Stony Brook University, Stony Brook, USA S.D. Webb Tech-X, Boulder, Colorado, USA
	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]

THEPPB002	High-Fidelity 3D Modulator Simulations of Coherent Electron Cooling Systems	3231
	G.I. Bell, D.L. Bruhwiler, I.V. Pogorelov, B.T. Schwartz Tech-X, Boulder, Colorado, USA Y. Hao, V. Litvinenko, G. Wang BNL, Upton, Long Island, New York, USA
	Funding: This work is supported by the US DOE Office of Science, Office of Nuclear Physics, grant numbers DE-SC0000835 and DE-FC02-07ER41499. Resources of NERSC were used under contract No. DE-AC02-05CH11231. Next generation electron-hadron colliders will require effective cooling of high-energy, high-intensity hadron beams. Coherent electron cooling (CeC) can in principle cool relativistic hadron beams on orders-of-magnitude shorter time scales than other techniques. The parallel VORPAL framework is used for 3D delta-f PIC simulations of anisotropic Debye shielding in a full longitudinal slice of the co-propagating electron beam, choosing parameters relevant to the proof-of-principle experiment under development at BNL. The transverse density conforms to an exponential Vlasov equilibrium for Gaussian velocities, with no longitudinal density variation. Comparison with 1D1V Vlasov/Poisson simulations shows good agreement in 1D. Parallel 3D simulations at NERSC show 3D effects for ions moving longitudinally and transversely. Simulation results are compared with the constant-density theory of Wang and Blaskiewicz. V.N. Litvinenko and Y.S. Derbenev, Phys. Rev. Lett. 10², 114801 (2009). ** Wang and Blaskiewicz, Phys Rev E 78, 026413 (2008).