2011 Particle Accelerator Conference - List of Authors (Qiang, J.)

Paper

Title

Page

Simulations of Space Charge in the Fermilab Main Injector

1654

E.G. Stern, J.F. Amundson, P. Spentzouris
Fermilab, Batavia, USA
J. Qiang, R.D. Ryne
LBNL, Berkeley, California, USA

The Fermilab Project X plan for future high intensity running relies on the Main Injector as the engine for delivering protons in the 60-120 GeV energy range. Project X plans call for increasing the number of protons per Main Injector bunch from the current value of 1.0× 10¹¹ to 3.0× 10¹¹. Space charge effects at the injection energy of 8 GeV have the potential to seriously disrupt operations. We report on ongoing simulations with Synergia, our multi-physics process accelerator modeling framework, to model space charge effects in the Main Injector combined with the effects of magnet fringe fields and apertures.

WEP152

Parallel Optimization of Beam-Beam Effects in High Energy Colliders

1770

J. Qiang, R.D. Ryne
LBNL, Berkeley, California, USA

Funding: Work supported by the Director of the Office of Science of the US Department of Energy under Contract no. DEAC02-05CH11231.
Beam-beam effects limit luminosity in high energy colliders. Parallel beam-beam simulation codes were developed to study those beam-beam effects and to help the collider design. In this paper, we will present a parallel optimization algorithm integrating together with the parallel beam-beam simulation to optimize the luminosity of the colliding beams. This algorithm is based on a differential evolutionary global optimization method and takes advantage of the two-level parallelization in both parallel search and parallel objective function evaluation. This significantly increases the scalability of the simulation on peta-scale supercomputers and reduces the time for finding the optimal working point.

THP180

Studies of a Linac Driver for a High Repetition Rate X-ray FEL

2450

M. Venturini, J.N. Corlett, L.R. Doolittle, D. Filippetto, C. F. Papadopoulos, G. Penn, D. Prosnitz, J. Qiang, M.W. Reinsch, R.D. Ryne, F. Sannibale, J.W. Staples, R.P. Wells, J.S. Wurtele, M.S. Zolotorev
LBNL, Berkeley, California, USA
A. Zholents
ANL, Argonne, USA

Funding: Work carried out under Department of Energy contract No. DE-AC02-0SCK11231
We report on on-going studies of a superconducting CW linac driver intended to support a high repetition rate FEL operating in the soft x-rays spectrum. We present a point-design for a 1.8 GeV machine tuned for 300~pC bunches and delivering low-emittance, low-energy spread beams as needed for the SASE and seeded beamlines.

THP200

Photoinjector Beam Dynamics for a Next Generation X-Ray FEL

2495

C. F. Papadopoulos, J.N. Corlett, D. Filippetto, G. Penn, J. Qiang, F. Sannibale, J.W. Staples, M. Venturini, R.P. Wells, M.S. Zolotorev
LBNL, Berkeley, California, USA

Funding: This work was supported by the Director of the Office of Science of the US Department of Energy under Contract no. DEAC02-05CH11231.
In this paper, we will present the status of the beam dynamics simulations for a Next Generation Light Source (NGLS) injector, based on a high repetition rate (1 MHz), high brightness design. A multi-stage beam compression scheme is proposed, based on the concepts of velocity bunching and emittance compensation. For the optimization of the design parameters we use a genetic algorithm approach, and we focus on a mode providing charges of 300 pC, with normalized transverse emittance less than 0.6 microns, suitable to operate a next generation light source based on an X-ray FEL. In addition, we discuss the effects of bunch compression and linearity of the transverse and longitudinal phase space of the beam.

TUOCS5

A Next Generation Light Source Facility at LBNL

775

J.N. Corlett, B. Austin, K.M. Baptiste, J.M. Byrd, P. Denes, R.J. Donahue, L.R. Doolittle, R.W. Falcone, D. Filippetto, D.S. Fournier, J. Kirz, D. Li, H.A. Padmore, C. F. Papadopoulos, G.C. Pappas, G. Penn, M. Placidi, S. Prestemon, D. Prosnitz, J. Qiang, A. Ratti, M.W. Reinsch, F. Sannibale, D. Schlueter, R.W. Schoenlein, J.W. Staples, T. Vecchione, M. Venturini, R.P. Wells, R.B. Wilcox, J.S. Wurtele
LBNL, Berkeley, California, USA
A.E. Charman, E. Kur
UCB, Berkeley, California, USA
A. Zholents
ANL, Argonne, USA

Funding: Work supported by the Director, Office of Science, of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231
The Next Generation Light Source (NGLS) is a design concept, under development at LBNL, for a multi‐beamline soft x‐ray FEL array powered by a 2 GeV superconducting linear accelerator, operating with a 1 MHz bunch repetition rate. The CW superconducting linear accelerator is supplied by a high-brightness, high-repetition-rate photocathode electron gun. Electron bunches are distributed from the linac to the array of independently configurable FEL beamlines with nominal bunch rates up to 100 kHz in each FEL, and with even pulse spacing. Individual FELs may be configured for EEHG, HGHG, SASE, or oscillator mode of operation, and will produce high peak and average brightness x-rays with a flexible pulse format, and with pulse durations ranging from sub-femtoseconds to hundreds of femtoseconds.

Slides TUOCS5 [4.758 MB]

Paper	Title	Page
WEP096	Simulations of Space Charge in the Fermilab Main Injector	1654
	E.G. Stern, J.F. Amundson, P. Spentzouris Fermilab, Batavia, USA J. Qiang, R.D. Ryne LBNL, Berkeley, California, USA
	The Fermilab Project X plan for future high intensity running relies on the Main Injector as the engine for delivering protons in the 60-120 GeV energy range. Project X plans call for increasing the number of protons per Main Injector bunch from the current value of 1.0× 10¹¹ to 3.0× 10¹¹. Space charge effects at the injection energy of 8 GeV have the potential to seriously disrupt operations. We report on ongoing simulations with Synergia, our multi-physics process accelerator modeling framework, to model space charge effects in the Main Injector combined with the effects of magnet fringe fields and apertures.

WEP152	Parallel Optimization of Beam-Beam Effects in High Energy Colliders	1770
	J. Qiang, R.D. Ryne LBNL, Berkeley, California, USA
	Funding: Work supported by the Director of the Office of Science of the US Department of Energy under Contract no. DEAC02-05CH11231. Beam-beam effects limit luminosity in high energy colliders. Parallel beam-beam simulation codes were developed to study those beam-beam effects and to help the collider design. In this paper, we will present a parallel optimization algorithm integrating together with the parallel beam-beam simulation to optimize the luminosity of the colliding beams. This algorithm is based on a differential evolutionary global optimization method and takes advantage of the two-level parallelization in both parallel search and parallel objective function evaluation. This significantly increases the scalability of the simulation on peta-scale supercomputers and reduces the time for finding the optimal working point.

THP180	Studies of a Linac Driver for a High Repetition Rate X-ray FEL	2450
	M. Venturini, J.N. Corlett, L.R. Doolittle, D. Filippetto, C. F. Papadopoulos, G. Penn, D. Prosnitz, J. Qiang, M.W. Reinsch, R.D. Ryne, F. Sannibale, J.W. Staples, R.P. Wells, J.S. Wurtele, M.S. Zolotorev LBNL, Berkeley, California, USA A. Zholents ANL, Argonne, USA
	Funding: Work carried out under Department of Energy contract No. DE-AC02-0SCK11231 We report on on-going studies of a superconducting CW linac driver intended to support a high repetition rate FEL operating in the soft x-rays spectrum. We present a point-design for a 1.8 GeV machine tuned for 300~pC bunches and delivering low-emittance, low-energy spread beams as needed for the SASE and seeded beamlines.

THP200	Photoinjector Beam Dynamics for a Next Generation X-Ray FEL	2495
	C. F. Papadopoulos, J.N. Corlett, D. Filippetto, G. Penn, J. Qiang, F. Sannibale, J.W. Staples, M. Venturini, R.P. Wells, M.S. Zolotorev LBNL, Berkeley, California, USA
	Funding: This work was supported by the Director of the Office of Science of the US Department of Energy under Contract no. DEAC02-05CH11231. In this paper, we will present the status of the beam dynamics simulations for a Next Generation Light Source (NGLS) injector, based on a high repetition rate (1 MHz), high brightness design. A multi-stage beam compression scheme is proposed, based on the concepts of velocity bunching and emittance compensation. For the optimization of the design parameters we use a genetic algorithm approach, and we focus on a mode providing charges of 300 pC, with normalized transverse emittance less than 0.6 microns, suitable to operate a next generation light source based on an X-ray FEL. In addition, we discuss the effects of bunch compression and linearity of the transverse and longitudinal phase space of the beam.

TUOCS5	A Next Generation Light Source Facility at LBNL	775
	J.N. Corlett, B. Austin, K.M. Baptiste, J.M. Byrd, P. Denes, R.J. Donahue, L.R. Doolittle, R.W. Falcone, D. Filippetto, D.S. Fournier, J. Kirz, D. Li, H.A. Padmore, C. F. Papadopoulos, G.C. Pappas, G. Penn, M. Placidi, S. Prestemon, D. Prosnitz, J. Qiang, A. Ratti, M.W. Reinsch, F. Sannibale, D. Schlueter, R.W. Schoenlein, J.W. Staples, T. Vecchione, M. Venturini, R.P. Wells, R.B. Wilcox, J.S. Wurtele LBNL, Berkeley, California, USA A.E. Charman, E. Kur UCB, Berkeley, California, USA A. Zholents ANL, Argonne, USA
	Funding: Work supported by the Director, Office of Science, of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231 The Next Generation Light Source (NGLS) is a design concept, under development at LBNL, for a multi‐beamline soft x‐ray FEL array powered by a 2 GeV superconducting linear accelerator, operating with a 1 MHz bunch repetition rate. The CW superconducting linear accelerator is supplied by a high-brightness, high-repetition-rate photocathode electron gun. Electron bunches are distributed from the linac to the array of independently configurable FEL beamlines with nominal bunch rates up to 100 kHz in each FEL, and with even pulse spacing. Individual FELs may be configured for EEHG, HGHG, SASE, or oscillator mode of operation, and will produce high peak and average brightness x-rays with a flexible pulse format, and with pulse durations ranging from sub-femtoseconds to hundreds of femtoseconds.
	Slides TUOCS5 [4.758 MB]