NAPAC2016 - List of Keywords (brightness)

Paper	Title	Other Keywords	Page
TUB4CO03	Optimization of Compton Source Performance Through Electron Beam Shaping	ion, electron, radiation, photon	474
	A. Malyzhenkov, N.A. Yampolsky LANL, Los Alamos, New Mexico, USA
	We investigate a novel scheme for significantly increasing the brightness of x-ray light sources based on inverse Compton scattering (ICS) - scattering laser pulses off relativistic electron beams. The brightness of these sources is limited by the electron beam quality since electrons traveling at different angles, and/or having different energies, produce photons with different energies. Therefore, the spectral brightness of the source is defined by the 6d electron phase space shape and size, as well as laser beam parameters. The peak brightness of the ICS source can be maximized then if the electron phase space is transformed in a way so that all electrons scatter off the x-ray photons of same frequency in the same direction. We describe the x-ray photon beam quality through the Wigner function (6d photon phase space distribution) and derive it for the ICS source when the electron and laser rms matrices are arbitrary. We find the optimal uncorrelated electron beam phase space distribution resulting in the highest brightness of the ICS source for the simple on axis case as an example.
	Slides TUB4CO03 [1.673 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-TUB4CO03
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WEPOA44	Accleration System of Beam Brightness Booster	ion, space-charge, proton, electron	796
	V.G. Dudnikov Muons, Inc, Illinois, USA A.V. Dudnikov BINP SB RAS, Novosibirsk, Russia
	The brightness and intensity of a circulating proton beam now can be increased up to space charge limit by means of charge exchange injection or by an electron cooling but cannot be increased above this limit. Significantly higher brightness can be produced by means of the charge exchange injection with the space charge compensation [1]. The brightness of the space charge compensated beam is limited at low level by development of the electron-proton (e-p) instability [2]. Fortunately, e-p instability can be self-stabilized at a high beam density. A beam brightness booster (BBB) for significant increase of accumulated beam brightness is discussed. Accelerating system with a space charge compensation is proposed and described. The superintense beam production can be simplified by developing of nonlinear nearly integrable focusing system with broad spread of betatron tune and the broadband feedback system for e-p instability suppression . [1] V. Dudnikov, in Proceedings of the Particle Accelerator Conference, Chicago, 2001.. [2] G. Budker, et al., Sov. Atomic Energy 22, 384 (1967);
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-WEPOA44
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WEPOA62	The Center for Bright Beams	ion, electron, cavity, cathode	830
	J.R. Patterson, G.H. Hoffstaetter Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA Y.K. Kim University of Chicago, Chicago, Illinois, USA
	Funding: National Science Foundation award PHY-1549132. The Center for Bright Beams (CBB) is a new National Science Foundation-supported Science and Technology Center. CBB's research goal is to increase the brightness of electron beams while reducing the cost and size of key technologies. To achieve this, it will augment the capabilities of accelerator physicists with those of physical chemists, materials scientists, condensed matter physicists, plasma physicists, and mathematicians. This approach has the potential to increase the brightness of electron sources through better photocathodes, the efficiency and gradient of SRF cavities through deeper understanding of superconducting compounds and their surfaces, and better understanding of beam storage and transport and the associated optics by using new mathematical techniques.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-WEPOA62
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WEPOB07	Dielectrically-Loaded Waveguide as a Short Period Superconducting Microwave Undulator	ion, undulator, operation, GUI	897
	R. Kustom, A. Nassiri, K.J. Suthar, G.J. Waldschmidt ANL, Argonne, Illinois, USA
	The HEM12 mode in a cylindrical, dielectrically-loaded waveguide provides E and H fields on the central axis that are significantly higher than the fields on the conducting walls. The waveguide is designed to operate near its cutoff frequency where the wavelength and phase velocity vary significantly to enable tuning of the equivalent undulator wavelength. The operating frequency would range from 18 - 24 GHz. It would be possible to generate coherent, high-energy 45 - 65 KeV x-rays from the fundamental mode which are tunable over a 20% energy range by changing the source frequency while maintaining constant field strengths. The x-ray brilliance of the microwave undulator would be 3 times higher at 56-KeV and 7 times higher at 66 KeV than what is available with the APS 1.8 cm period Superconducting Wire Undulator. Since the loss factor of sapphire is very low at cryogenic temperatures, it is possible to consider a superconducting microwave undulator, although resistive losses of ~200 to 700 W/m may be a bit too high for CW operation.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-WEPOB07
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THA2CO03	New 1.4 Cell RF Photoinjector Design for High Brightness Beam Generation	ion, cathode, laser, electron	1083
	E. Pirez, P. Musumeci UCLA, Los Angeles, California, USA D. Alesini INFN/LNF, Frascati (Roma), Italy J.M. Maxson Cornell University, Ithaca, New York, USA
	Funding: This work was partially funded by NSF grant 145583 The new electromagnetic and mechanical designs of the S-band 1.4 cell photoinjector are discussed. A novel fabrication method is adopted to replace the brazing process with a clamping technique achieving lower breakdown probability. The photoinjector is designed to operate at a 120 MV/m gradient and an optimal injection phase of 70 degrees to improve the extraction field by a factor of 1.9 compared to standard 1.6 cell designs with the same peak field. New geometries and features are implemented to improve beam quality for the demand of high brightness beam applications.
	Slides THA2CO03 [2.444 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-THA2CO03
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THPOA04	Maximum Brightness of Linac-Driven Electron Beams in the Presence of Collective Effects	ion, linac, electron, emittance	1101
	S. Di Mitri Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Italy
	Linear accelerators capable of delivering high brightness electron beams are essential components of a number of research tools, such as free electron lasers (FELs) and elementary particle colliders. In these facilities the charge density is high enough to drive undesirable collective effects (wakefields) that may increase the beam emittance relative to the injection level, eventually degrading the nominal brightness. We formulate a limit on the final electron beam brightness, imposed by the interplay of geometric transverse wakefield in accelerating structures and coherent synchrotron radiation in energy dispersive regions. Numerous experimental data of VUV and X-ray FEL drivers validate our model. This is then used to show that a normalized brightness of 10¹⁶ A/m², promised so far by ultra-low charge beams (1-10 pC), can in fact be reached with a 100 pC charge beam in the Italian FERMI FEL linac, with the existing machine configuration.* Physical Review Special Topics - Accelerators And Beams 17, 110702 (2014) *Physical Review Special Topics - Accelerators And Beams 16, 050701 (2013)
	Poster THPOA04 [0.828 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-THPOA04
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Other Keywords

Page

TUB4CO03

Optimization of Compton Source Performance Through Electron Beam Shaping

ion, electron, radiation, photon

474

A. Malyzhenkov, N.A. Yampolsky
LANL, Los Alamos, New Mexico, USA

We investigate a novel scheme for significantly increasing the brightness of x-ray light sources based on inverse Compton scattering (ICS) - scattering laser pulses off relativistic electron beams. The brightness of these sources is limited by the electron beam quality since electrons traveling at different angles, and/or having different energies, produce photons with different energies. Therefore, the spectral brightness of the source is defined by the 6d electron phase space shape and size, as well as laser beam parameters. The peak brightness of the ICS source can be maximized then if the electron phase space is transformed in a way so that all electrons scatter off the x-ray photons of same frequency in the same direction. We describe the x-ray photon beam quality through the Wigner function (6d photon phase space distribution) and derive it for the ICS source when the electron and laser rms matrices are arbitrary. We find the optimal uncorrelated electron beam phase space distribution resulting in the highest brightness of the ICS source for the simple on axis case as an example.

Slides TUB4CO03 [1.673 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-TUB4CO03

Export •

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

WEPOA44

Accleration System of Beam Brightness Booster

ion, space-charge, proton, electron

796

V.G. Dudnikov
Muons, Inc, Illinois, USA
A.V. Dudnikov
BINP SB RAS, Novosibirsk, Russia

The brightness and intensity of a circulating proton beam now can be increased up to space charge limit by means of charge exchange injection or by an electron cooling but cannot be increased above this limit. Significantly higher brightness can be produced by means of the charge exchange injection with the space charge compensation [1]. The brightness of the space charge compensated beam is limited at low level by development of the electron-proton (e-p) instability [2]. Fortunately, e-p instability can be self-stabilized at a high beam density. A beam brightness booster (BBB) for significant increase of accumulated beam brightness is discussed. Accelerating system with a space charge compensation is proposed and described. The superintense beam production can be simplified by developing of nonlinear nearly integrable focusing system with broad spread of betatron tune and the broadband feedback system for e-p instability suppression .
[1] V. Dudnikov, in Proceedings of the Particle Accelerator Conference, Chicago, 2001..
[2] G. Budker, et al., Sov. Atomic Energy 22, 384 (1967);

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-WEPOA44

Export •

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

WEPOA62

The Center for Bright Beams

ion, electron, cavity, cathode

830

J.R. Patterson, G.H. Hoffstaetter
Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
Y.K. Kim
University of Chicago, Chicago, Illinois, USA

Funding: National Science Foundation award PHY-1549132.
The Center for Bright Beams (CBB) is a new National Science Foundation-supported Science and Technology Center. CBB's research goal is to increase the brightness of electron beams while reducing the cost and size of key technologies. To achieve this, it will augment the capabilities of accelerator physicists with those of physical chemists, materials scientists, condensed matter physicists, plasma physicists, and mathematicians. This approach has the potential to increase the brightness of electron sources through better photocathodes, the efficiency and gradient of SRF cavities through deeper understanding of superconducting compounds and their surfaces, and better understanding of beam storage and transport and the associated optics by using new mathematical techniques.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-WEPOA62

Export •

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

WEPOB07

Dielectrically-Loaded Waveguide as a Short Period Superconducting Microwave Undulator

ion, undulator, operation, GUI

897

R. Kustom, A. Nassiri, K.J. Suthar, G.J. Waldschmidt
ANL, Argonne, Illinois, USA

The HEM12 mode in a cylindrical, dielectrically-loaded waveguide provides E and H fields on the central axis that are significantly higher than the fields on the conducting walls. The waveguide is designed to operate near its cutoff frequency where the wavelength and phase velocity vary significantly to enable tuning of the equivalent undulator wavelength. The operating frequency would range from 18 - 24 GHz. It would be possible to generate coherent, high-energy 45 - 65 KeV x-rays from the fundamental mode which are tunable over a 20% energy range by changing the source frequency while maintaining constant field strengths. The x-ray brilliance of the microwave undulator would be 3 times higher at 56-KeV and 7 times higher at 66 KeV than what is available with the APS 1.8 cm period Superconducting Wire Undulator. Since the loss factor of sapphire is very low at cryogenic temperatures, it is possible to consider a superconducting microwave undulator, although resistive losses of ~200 to 700 W/m may be a bit too high for CW operation.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-WEPOB07

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THA2CO03

New 1.4 Cell RF Photoinjector Design for High Brightness Beam Generation

ion, cathode, laser, electron

1083

E. Pirez, P. Musumeci
UCLA, Los Angeles, California, USA
D. Alesini
INFN/LNF, Frascati (Roma), Italy
J.M. Maxson
Cornell University, Ithaca, New York, USA

Funding: This work was partially funded by NSF grant 145583
The new electromagnetic and mechanical designs of the S-band 1.4 cell photoinjector are discussed. A novel fabrication method is adopted to replace the brazing process with a clamping technique achieving lower breakdown probability. The photoinjector is designed to operate at a 120 MV/m gradient and an optimal injection phase of 70 degrees to improve the extraction field by a factor of 1.9 compared to standard 1.6 cell designs with the same peak field. New geometries and features are implemented to improve beam quality for the demand of high brightness beam applications.

Slides THA2CO03 [2.444 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-THA2CO03

Export •

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

THPOA04

Maximum Brightness of Linac-Driven Electron Beams in the Presence of Collective Effects

ion, linac, electron, emittance

1101

S. Di Mitri
Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Italy

Linear accelerators capable of delivering high brightness electron beams are essential components of a number of research tools, such as free electron lasers (FELs) and elementary particle colliders. In these facilities the charge density is high enough to drive undesirable collective effects (wakefields) that may increase the beam emittance relative to the injection level, eventually degrading the nominal brightness. We formulate a limit on the final electron beam brightness, imposed by the interplay of geometric transverse wakefield in accelerating structures and coherent synchrotron radiation in energy dispersive regions*. Numerous experimental data of VUV and X-ray FEL drivers validate our model. This is then used to show that a normalized brightness of 10¹⁶ A/m², promised so far by ultra-low charge beams (1-10 pC), can in fact be reached with a 100 pC charge beam in the Italian FERMI FEL linac, with the existing machine configuration.**
*Physical Review Special Topics - Accelerators And Beams 17, 110702 (2014)
**Physical Review Special Topics - Accelerators And Beams 16, 050701 (2013)

Poster THPOA04 [0.828 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-NAPAC2016-THPOA04

Export •

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