IPAC2015 - Table of Session: MOBC (Contributed Orals (MC5))

Paper	Title	Page
MOBC1	Towards Ultra-Low β^* in ATF2	38
	M. Patecki, A.V. Aloev, D.R. Bett, M. Modena, R. Tomás CERN, Geneva, Switzerland K. Kubo, T. Okugi, T. Tauchi, N. Terunuma KEK, Ibaraki, Japan E. Marín, G.R. White SLAC, Menlo Park, California, USA
	The Accelerator Test Facility 2 (ATF2) has already demonstrated the feasibility of Final Focus Systems based on the local chromaticity correction scheme and its focusing capabilities by reaching a vertical beam size at the virtual Interaction Point (IP) of less than 50 nm. The value of the chromaticity in ATF2 is comparable with the expected chromaticity in ILC, but 4 times lower than in a design of CLIC. ATF2 gives the unique possibility to test operation at CLIC chromaticity values by reducing the vertical beta function at the IP by a factor of 4 (the inverse proportionality of chromaticity with beta function value at IP is assumed). The experience collected in this way would be beneficial for both ILC and CLIC projects. Simulations show that the multipolar errors and Final Doublet fringe fields spoil the IP beam sizes at ATF2. Either increasing a value of the horizontal beta function or installing a pair of octupole magnets mitigate the impact of these aberrations. This paper summarizes the studies towards the realization of the ultra-low β^* optics in ATF2 and reports on the progress of the construction of the octupoles.
	Slides MOBC1 [1.566 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-MOBC1
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MOBC2	High-Performance Simulations of Coherent Synchrotron Radiation on Multicore GPU and CPU Platforms	42
	B. Terzić, A.L. Godunov ODU, Norfolk, Virginia, USA A. Arumugam, D. Ranjan, M. Zubair ODU CS, Norfolk, Virginia, USA
	Coherent synchrotron radiation (CSR) is an effect of self-interaction of an electron bunch as it traverses a curved path. It can cause a significant emittance degradation and microbunching. We present a new high-performance 2D, particle-in-cell code which uses massively parallel multicore GPU/GPU platforms to alleviate computational bottlenecks. The code formulates the CSR problem from first principles by using the retarded scalar and vector potentials to compute the self-interaction fields. The speedup due to the parallel implementation on GPU/CPU platforms exceeds three orders of magnitude, thereby bringing a previously intractable problem within reach. The accuracy of the code is verified against analytic 1D solutions (rigid bunch).
	Slides MOBC2 [4.866 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-MOBC2
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOBC3	Electron Lenses for Experiments on Nonlinear Dynamics with Wide Stable Tune Spreads in the Fermilab Integrable Optics Test Accelerator	46
	G. Stancari, K. Carlson, M.W. McGee, L.E. Nobrega, A.L. Romanov, J. Ruan, A. Valishev Fermilab, Batavia, Illinois, USA D. Noll IAP, Frankfurt am Main, Germany
	Funding: Fermilab is operated by Fermi Research Alliance, LLC, under Contract DE-AC02-07CH11359 with the US Department of Energy. Recent developments in the study of integrable Hamiltonian systems have led to nonlinear accelerator lattice designs with two transverse invariants. These lattices may drastically improve the performance of high-power machines, providing wide tune spreads and Landau damping to protect the beam from instabilities, while preserving dynamic aperture. To test the feasibility of these concepts, the Integrable Optics Test Accelerator (IOTA) is being designed and built at Fermilab. One way to obtain a nonlinear integrable lattice is by using the fields generated by a magnetically confined electron beam (electron lens) overlapping with the circulating beam. The parameters of the required device are similar to the ones of existing electron lenses. We present theory, numerical simulations, and first design studies of electron lenses for nonlinear integrable optics.
	Slides MOBC3 [11.870 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-MOBC3
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Towards Ultra-Low β^* in ATF2

38

M. Patecki, A.V. Aloev, D.R. Bett, M. Modena, R. Tomás
CERN, Geneva, Switzerland
K. Kubo, T. Okugi, T. Tauchi, N. Terunuma
KEK, Ibaraki, Japan
E. Marín, G.R. White
SLAC, Menlo Park, California, USA

The Accelerator Test Facility 2 (ATF2) has already demonstrated the feasibility of Final Focus Systems based on the local chromaticity correction scheme and its focusing capabilities by reaching a vertical beam size at the virtual Interaction Point (IP) of less than 50 nm. The value of the chromaticity in ATF2 is comparable with the expected chromaticity in ILC, but 4 times lower than in a design of CLIC. ATF2 gives the unique possibility to test operation at CLIC chromaticity values by reducing the vertical beta function at the IP by a factor of 4 (the inverse proportionality of chromaticity with beta function value at IP is assumed). The experience collected in this way would be beneficial for both ILC and CLIC projects. Simulations show that the multipolar errors and Final Doublet fringe fields spoil the IP beam sizes at ATF2. Either increasing a value of the horizontal beta function or installing a pair of octupole magnets mitigate the impact of these aberrations. This paper summarizes the studies towards the realization of the ultra-low β^* optics in ATF2 and reports on the progress of the construction of the octupoles.

Slides MOBC1 [1.566 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-MOBC1

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOBC2

High-Performance Simulations of Coherent Synchrotron Radiation on Multicore GPU and CPU Platforms

42

B. Terzić, A.L. Godunov
ODU, Norfolk, Virginia, USA
A. Arumugam, D. Ranjan, M. Zubair
ODU CS, Norfolk, Virginia, USA

Coherent synchrotron radiation (CSR) is an effect of self-interaction of an electron bunch as it traverses a curved path. It can cause a significant emittance degradation and microbunching. We present a new high-performance 2D, particle-in-cell code which uses massively parallel multicore GPU/GPU platforms to alleviate computational bottlenecks. The code formulates the CSR problem from first principles by using the retarded scalar and vector potentials to compute the self-interaction fields. The speedup due to the parallel implementation on GPU/CPU platforms exceeds three orders of magnitude, thereby bringing a previously intractable problem within reach. The accuracy of the code is verified against analytic 1D solutions (rigid bunch).

Slides MOBC2 [4.866 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-MOBC2

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOBC3

Electron Lenses for Experiments on Nonlinear Dynamics with Wide Stable Tune Spreads in the Fermilab Integrable Optics Test Accelerator

46

G. Stancari, K. Carlson, M.W. McGee, L.E. Nobrega, A.L. Romanov, J. Ruan, A. Valishev
Fermilab, Batavia, Illinois, USA
D. Noll
IAP, Frankfurt am Main, Germany

Funding: Fermilab is operated by Fermi Research Alliance, LLC, under Contract DE-AC02-07CH11359 with the US Department of Energy.
Recent developments in the study of integrable Hamiltonian systems have led to nonlinear accelerator lattice designs with two transverse invariants. These lattices may drastically improve the performance of high-power machines, providing wide tune spreads and Landau damping to protect the beam from instabilities, while preserving dynamic aperture. To test the feasibility of these concepts, the Integrable Optics Test Accelerator (IOTA) is being designed and built at Fermilab. One way to obtain a nonlinear integrable lattice is by using the fields generated by a magnetically confined electron beam (electron lens) overlapping with the circulating beam. The parameters of the required device are similar to the ones of existing electron lenses. We present theory, numerical simulations, and first design studies of electron lenses for nonlinear integrable optics.

Slides MOBC3 [11.870 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-MOBC3

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)