FEL2017 - List of Authors (Marinelli, A.)

Paper	Title	Page
MOBB02	Temporal and Spatial Shaping of X-Ray Free-Electron Lasers
	A. Marinelli SLAC, Menlo Park, California, USA
	The x-ray free-electron laser is the brightest source of x-rays, with a peak brightness ten orders of magnitude higher than conventional synchrotron radiation sources. Much like conventional lasers, XFELs are extremely flexible machines and the properties of the x-rays can be controlled by accurately manipulating the lasing medium, i.e. the electron beam. In my talk I will discuss past and present research on shaping the temporal properties of the x-rays at the Linac Coherent Light Source (LCLS). I will discuss the two-color FEL modes and their applications in user experiments. Finally I will present our results on laser-shaping of x-ray pulses and our plans for attosecond operation in the soft x-ray regime.
	Slides MOBB02 [1.289 MB]
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TUA05	Generating Subfemtosecond Hard X-Ray Pulses with Optimized Nonlinear Bunch Compression
	S. Huang PKU, Beijing, People's Republic of China Y. Ding, Y. Feng, E. Hemsing, Z. Huang, J. Krzywinski, A.A. Lutman, A. Marinelli, T.J. Maxwell, D. Zhu SLAC, Menlo Park, California, USA
	Funding: This work is supported by the U.S. Department of Energy Contract No. DE-AC02-76SF00515 and the National Key Research and Development Program of China (Grant No. 2016YFA0401904). A simple method for generating single-spike hard x-ray pulses in free-electron lasers (FELs) has been developed at the Linac Coherent Light Source (LCLS). By optimizing the electron bunch compression in experiments, we have obtained half of the hard x-ray FEL shots containing single-spike spectrum. At 5.6-keV photon energy, the single-spike shots have a mean pulse energy of about 10 J with 70% intensity fluctuation and the pulse width (full width at half maximum) is evaluated to be at 200-attosecond level.
	Slides TUA05 [3.854 MB]
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TUP058	Slippage-Enhanced SASE FEL	348
	J. Wu, A. Brachmann, K. Fang, A. Marinelli, C. Pellegrini, T.O. Raubenheimer, C.-Y. Tsai, C. Yang, M. Yoon, G. Zhou SLAC, Menlo Park, California, USA H.-S. Kang, G. Kim, I.H. Nam PAL, Pohang, Republic of Korea B. Yang University of Texas at Arlington, Arlington, USA
	Funding: The work was supported by the US Department of Energy (DOE) under contract DE-AC02-76SF00515 and the US DOE Office of Science Early Career Research Program grant FWP-2013-SLAC-100164. High-brightness XFEL is demanding for many users, in particular for certain types of imaging applications. Seeded FELs including self-seeding XFELs were successfully demonstrated. Alternative approaches by enhancing slippage between the x-ray pulse and the electron bunch were also demonstrated. This class of Slippage-enhanced SASE (SeSASE) schemes can be unique for FEL spectral range between 1.5 keV to 4 keV where neither grating-based soft x-ray self-seeding nor crystal-based hard x-ray self-seeding can easily access. SeSASE can provide high-brightness XFEL for high repetition rate machines not suffering from heat load on the crystal monochromator. We report start-to-end simulation results for LCLS-II project and PAL-XFEL project with study on tolerance. Performance comparison between SaSASE FEL and self-seeding FEL in the overlapping frequency range is also presented.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2017-TUP058
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WEP060	Characterizing Sub-Femtosecond X-ray Pulses from the Linac Coherent Light Source	535
	S. Li, R.N. Coffee, J. Cryan, K.H. Hegazy, Z. Huang, A. Marinelli, A. Natan, T. Osipov, D. Ray SLAC, Menlo Park, California, USA G. Guo Stanford University, Stanford, California, USA
	The development of sub-femtosecond x-ray capabilities at the Linac Coherent Light Source requires the implementation of time-domain diagnostics with attosecond (as) time resolution. Photoelectrons created by attosecond duration x-ray pulses in the presence of a strong-laser field are known to suffer an energy spread which depends on the relative phase of the strong-laser field at the time of ionization. This phenomenon can be exploited to measure the duration of these ultrashort x-ray pulses. We present an implementation which employs a circularly polarized infrared laser pulse and novel velocity map imaging design which maps the phase dependent momentum of the photoelectron onto a 2-D detector. In this paper, we present the novel co-linear VMI design, simulation of the photoelectron momentum distribution, and the reconstruction algorithm.
	Poster WEP060 [1.260 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2017-WEP060
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FRA01	Fresh-Slice X-Ray Free Electron Laser Schemes for Advanced X-Ray Applications
	A.A. Lutman, R.N. Coffee, Y. Ding, J.P. Duris, M.W. Guetg, Z. Huang, J. Krzywinski, J.P. MacArthur, A. Marinelli, T.J. Maxwell, S.P. Moeller, J. Zemella SLAC, Menlo Park, California, USA N. Berrah University of Connecticut, Storrs, Connecticut, USA C. Emma UCLA, Los Angeles, USA
	Funding: This work was supported by Department of Energy contract nos DE-AC02-76SF00515 and DE-SC0012376 The novel fresh-slice XFEL scheme grants control on the temporal slice of the electron bunch lasing in each undulator section. The technique relies on a time-dependent electron bunch trajectory impressed by the transverse wakefield of a corrugated structure and subsequent orbit manipulation in the undulator section. Fully saturated double pulses are produced in two different undulator sections. The wavelength of each pulse is controlled by the undulator magnetic strength and the delay between the pulses can be scanned from a few femtosecond advance of the pulse generated on the bunch head in the second section to a picosecond delay provided by the magnetic chicane. Three-color saturated pulses are demonstrated by using three undulator sections and the polarization of the pulse generated in the last section can be controlled by the variable polarization Delta undulator. In this work we also show the early results for the first multi-stage amplification scheme, producing ultra-short single-pulses with a 100-GW power level in the soft X-rays. The multi-stage amplification is also demonstrated to improve the performance in power and pulse duration control for the two-color FEL scheme.
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FRB01	Time-Domain Analysis of Attosecond Pulse Generation in an X-Ray Free-Electron Laser	569
	P. Baxevanis, Z. Huang, A. Marinelli SLAC, Menlo Park, California, USA
	The method of enhanced self-amplified spontaneous emission (eSASE) is one of the strongest candidates for the generation of sub-femtosecond X-ray pulses in a free-electron laser. The optimization of an eSASE experiment involves many independent parameters, which makes the exploration of the parameter space with 3-D simulations computationally intensive. Therefore, a robust theoretical analysis of this problem is extremely desirable. We provide a self-consistent, analytical treatment of such a configuration using a one-dimensional, time-dependent FEL model that includes the key effects of linear e-beam chirp and linear undulator taper. Verified via comparison with numerical simulation, our formalism is also utilized in parameter studies that seek to determine the optimum setup of the FEL.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2017-FRB01
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Paper

Title

Page

MOBB02

Temporal and Spatial Shaping of X-Ray Free-Electron Lasers

A. Marinelli
SLAC, Menlo Park, California, USA

The x-ray free-electron laser is the brightest source of x-rays, with a peak brightness ten orders of magnitude higher than conventional synchrotron radiation sources. Much like conventional lasers, XFELs are extremely flexible machines and the properties of the x-rays can be controlled by accurately manipulating the lasing medium, i.e. the electron beam. In my talk I will discuss past and present research on shaping the temporal properties of the x-rays at the Linac Coherent Light Source (LCLS). I will discuss the two-color FEL modes and their applications in user experiments. Finally I will present our results on laser-shaping of x-ray pulses and our plans for attosecond operation in the soft x-ray regime.

Slides MOBB02 [1.289 MB]

Export •

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

TUA05

Generating Subfemtosecond Hard X-Ray Pulses with Optimized Nonlinear Bunch Compression

S. Huang
PKU, Beijing, People's Republic of China
Y. Ding, Y. Feng, E. Hemsing, Z. Huang, J. Krzywinski, A.A. Lutman, A. Marinelli, T.J. Maxwell, D. Zhu
SLAC, Menlo Park, California, USA

Funding: This work is supported by the U.S. Department of Energy Contract No. DE-AC02-76SF00515 and the National Key Research and Development Program of China (Grant No. 2016YFA0401904).
A simple method for generating single-spike hard x-ray pulses in free-electron lasers (FELs) has been developed at the Linac Coherent Light Source (LCLS). By optimizing the electron bunch compression in experiments, we have obtained half of the hard x-ray FEL shots containing single-spike spectrum. At 5.6-keV photon energy, the single-spike shots have a mean pulse energy of about 10 J with 70% intensity fluctuation and the pulse width (full width at half maximum) is evaluated to be at 200-attosecond level.

Slides TUA05 [3.854 MB]

Export •

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

TUP058

Slippage-Enhanced SASE FEL

348

J. Wu, A. Brachmann, K. Fang, A. Marinelli, C. Pellegrini, T.O. Raubenheimer, C.-Y. Tsai, C. Yang, M. Yoon, G. Zhou
SLAC, Menlo Park, California, USA
H.-S. Kang, G. Kim, I.H. Nam
PAL, Pohang, Republic of Korea
B. Yang
University of Texas at Arlington, Arlington, USA

Funding: The work was supported by the US Department of Energy (DOE) under contract DE-AC02-76SF00515 and the US DOE Office of Science Early Career Research Program grant FWP-2013-SLAC-100164.
High-brightness XFEL is demanding for many users, in particular for certain types of imaging applications. Seeded FELs including self-seeding XFELs were successfully demonstrated. Alternative approaches by enhancing slippage between the x-ray pulse and the electron bunch were also demonstrated. This class of Slippage-enhanced SASE (SeSASE) schemes can be unique for FEL spectral range between 1.5 keV to 4 keV where neither grating-based soft x-ray self-seeding nor crystal-based hard x-ray self-seeding can easily access. SeSASE can provide high-brightness XFEL for high repetition rate machines not suffering from heat load on the crystal monochromator. We report start-to-end simulation results for LCLS-II project and PAL-XFEL project with study on tolerance. Performance comparison between SaSASE FEL and self-seeding FEL in the overlapping frequency range is also presented.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2017-TUP058

Export •

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

WEP060

Characterizing Sub-Femtosecond X-ray Pulses from the Linac Coherent Light Source

535

S. Li, R.N. Coffee, J. Cryan, K.H. Hegazy, Z. Huang, A. Marinelli, A. Natan, T. Osipov, D. Ray
SLAC, Menlo Park, California, USA
G. Guo
Stanford University, Stanford, California, USA

The development of sub-femtosecond x-ray capabilities at the Linac Coherent Light Source requires the implementation of time-domain diagnostics with attosecond (as) time resolution. Photoelectrons created by attosecond duration x-ray pulses in the presence of a strong-laser field are known to suffer an energy spread which depends on the relative phase of the strong-laser field at the time of ionization. This phenomenon can be exploited to measure the duration of these ultrashort x-ray pulses. We present an implementation which employs a circularly polarized infrared laser pulse and novel velocity map imaging design which maps the phase dependent momentum of the photoelectron onto a 2-D detector. In this paper, we present the novel co-linear VMI design, simulation of the photoelectron momentum distribution, and the reconstruction algorithm.

Poster WEP060 [1.260 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2017-WEP060

Export •

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

FRA01

Fresh-Slice X-Ray Free Electron Laser Schemes for Advanced X-Ray Applications

A.A. Lutman, R.N. Coffee, Y. Ding, J.P. Duris, M.W. Guetg, Z. Huang, J. Krzywinski, J.P. MacArthur, A. Marinelli, T.J. Maxwell, S.P. Moeller, J. Zemella
SLAC, Menlo Park, California, USA
N. Berrah
University of Connecticut, Storrs, Connecticut, USA
C. Emma
UCLA, Los Angeles, USA

Funding: This work was supported by Department of Energy contract nos DE-AC02-76SF00515 and DE-SC0012376
The novel fresh-slice XFEL scheme grants control on the temporal slice of the electron bunch lasing in each undulator section. The technique relies on a time-dependent electron bunch trajectory impressed by the transverse wakefield of a corrugated structure and subsequent orbit manipulation in the undulator section. Fully saturated double pulses are produced in two different undulator sections. The wavelength of each pulse is controlled by the undulator magnetic strength and the delay between the pulses can be scanned from a few femtosecond advance of the pulse generated on the bunch head in the second section to a picosecond delay provided by the magnetic chicane. Three-color saturated pulses are demonstrated by using three undulator sections and the polarization of the pulse generated in the last section can be controlled by the variable polarization Delta undulator. In this work we also show the early results for the first multi-stage amplification scheme, producing ultra-short single-pulses with a 100-GW power level in the soft X-rays. The multi-stage amplification is also demonstrated to improve the performance in power and pulse duration control for the two-color FEL scheme.

Export •

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

FRB01

Time-Domain Analysis of Attosecond Pulse Generation in an X-Ray Free-Electron Laser

569

P. Baxevanis, Z. Huang, A. Marinelli
SLAC, Menlo Park, California, USA

The method of enhanced self-amplified spontaneous emission (eSASE) is one of the strongest candidates for the generation of sub-femtosecond X-ray pulses in a free-electron laser. The optimization of an eSASE experiment involves many independent parameters, which makes the exploration of the parameter space with 3-D simulations computationally intensive. Therefore, a robust theoretical analysis of this problem is extremely desirable. We provide a self-consistent, analytical treatment of such a configuration using a one-dimensional, time-dependent FEL model that includes the key effects of linear e-beam chirp and linear undulator taper. Verified via comparison with numerical simulation, our formalism is also utilized in parameter studies that seek to determine the optimum setup of the FEL.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2017-FRB01

Export •

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