IPAC2019 - List of Authors (Pop, M.A.)

Paper	Title	Page
TUPRB070	A Peak Finding Algorithm for FEL Spectra Characterization	1827
	M.A. Pop MAX IV Laboratory, Lund University, Lund, Sweden E. Allaria Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Italy
	We present a software tool aimed at investigating the spectra of photon sources in order to detect any instabilities in the electron beam that have a clear effect on the spectrum. The method has been developed for FERMI@Elettra but with a general approach on the particularities of FEL machines such as a high repetition frequency and significant shot to shot fluctuations. The software has two operating options: a mode, aimed at online usage, which only detects peaks and their corresponding valleys, offering no information about the peaks themselves; and a more comprehensive mode that fits peak functions (Gaussian, Lorentzian etc…) to the spectrum based on initial guesses of the fitting parameters. The algorithm can provide a collection of simple but valuable variables such as number of peaks, peak separation and ratio between peak heights, as well as more specialized variables like peak width statistics and decomposition of the raw spectrum in basic components. Project done in collaboration with FERMI@Elettra
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-TUPRB070
About •	paper received ※ 15 May 2019 paper accepted ※ 23 May 2019 issue date ※ 21 June 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPRB071	Considerations on Implementing EEHG with a Strong Linear Chirp	1830
SUSPFO093	use link to see paper's listing under its alternate paper code
	M.A. Pop, S. Werin MAX IV Laboratory, Lund University, Lund, Sweden
	As the ECHO enabled harmonic generation (EEHG) scheme draws such intense focus from the FEL community, we conduct simulations to evaluate the challenges of implementing said scheme in different FEL layouts. Nonlinear processes such as this require extensive simulations to harmonize all system specific properties like seed lasers and electron beam properties. Along with optimizing the original EEHG scheme* one can consider, for example, altering the seed laser pulse to optimize the bunching for a machine specific chirp. We study the EEHG as a possible seeding method aimed at increasing coherence of the photon beam for the prospective SXL FEL beamline at MAXIV. The particular chirp of the electron beam through the MAXIV LINAC generates some specific requirements in implementing EEHG but may also offer an opportunity for exotic operation modes of this FEL. * Xiang D. and Stupakov G. Echo-enabled harmonic generation free electron laser 10.1103/PhysRevSTAB.12.030702
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-TUPRB071
About •	paper received ※ 15 May 2019 paper accepted ※ 23 May 2019 issue date ※ 21 June 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEXXPLM1	Amplified Emission of a Soft-X Ray Free-Electron Laser Based on Echo-Enabled Harmonic Generation	2230
	E. Allaria, L. Badano, G. De Ninno, S. Di Mitri, B. Diviacco, W.M. Fawley, N.S. Mirian, G. Penco, P. Rebernik Ribič, S. Spampinati, C. Spezzani, M. Trovò Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Italy G. De Ninno University of Nova Gorica, Nova Gorica, Slovenia E. Ferrari, E. Prat PSI, Villigen PSI, Switzerland D. Garzella CEA, Gif-sur-Yvette, France V. Grattoni DESY, Hamburg, Germany E. Hemsing SLAC, Menlo Park, California, USA M.A. Pop MAX IV Laboratory, Lund University, Lund, Sweden E. Roussel PhLAM/CERLA, Villeneuve d’Ascq, France D. Xiang Shanghai Jiao Tong University, Shanghai, People’s Republic of China
	We report the first evidence of substantial gain in a soft-X ray Free Electron Laser (FEL) based on Echo-Enabled Harmonic Generation (EEHG). The experiment was focused on harmonics 36 (~7.3nm) and 45 (5.8 nm) and clearly demonstrated the expected EEHG capability of generating powerful and coherent FEL pulses, with strongly reduced sensitivity to electron-beam fluctuations. The experiment was carried out at FERMI, the seeded FEL user facility at Elettra-Sincrotrone Trieste.
	Slides WEXXPLM1 [11.410 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-WEXXPLM1
About •	paper received ※ 17 May 2019 paper accepted ※ 23 May 2019 issue date ※ 21 June 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

A Peak Finding Algorithm for FEL Spectra Characterization

1827

M.A. Pop
MAX IV Laboratory, Lund University, Lund, Sweden
E. Allaria
Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Italy

We present a software tool aimed at investigating the spectra of photon sources in order to detect any instabilities in the electron beam that have a clear effect on the spectrum. The method has been developed for FERMI@Elettra but with a general approach on the particularities of FEL machines such as a high repetition frequency and significant shot to shot fluctuations. The software has two operating options: a mode, aimed at online usage, which only detects peaks and their corresponding valleys, offering no information about the peaks themselves; and a more comprehensive mode that fits peak functions (Gaussian, Lorentzian etc…) to the spectrum based on initial guesses of the fitting parameters. The algorithm can provide a collection of simple but valuable variables such as number of peaks, peak separation and ratio between peak heights, as well as more specialized variables like peak width statistics and decomposition of the raw spectrum in basic components.
Project done in collaboration with FERMI@Elettra

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-TUPRB070

About •

paper received ※ 15 May 2019 paper accepted ※ 23 May 2019 issue date ※ 21 June 2019

Export •

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

TUPRB071

Considerations on Implementing EEHG with a Strong Linear Chirp

1830

SUSPFO093

use link to see paper's listing under its alternate paper code

M.A. Pop, S. Werin
MAX IV Laboratory, Lund University, Lund, Sweden

As the ECHO enabled harmonic generation (EEHG) scheme draws such intense focus from the FEL community, we conduct simulations to evaluate the challenges of implementing said scheme in different FEL layouts. Nonlinear processes such as this require extensive simulations to harmonize all system specific properties like seed lasers and electron beam properties. Along with optimizing the original EEHG scheme* one can consider, for example, altering the seed laser pulse to optimize the bunching for a machine specific chirp. We study the EEHG as a possible seeding method aimed at increasing coherence of the photon beam for the prospective SXL FEL beamline at MAXIV. The particular chirp of the electron beam through the MAXIV LINAC generates some specific requirements in implementing EEHG but may also offer an opportunity for exotic operation modes of this FEL.
* Xiang D. and Stupakov G. Echo-enabled harmonic generation free electron laser 10.1103/PhysRevSTAB.12.030702

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-TUPRB071

About •

paper received ※ 15 May 2019 paper accepted ※ 23 May 2019 issue date ※ 21 June 2019

Export •

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

WEXXPLM1

Amplified Emission of a Soft-X Ray Free-Electron Laser Based on Echo-Enabled Harmonic Generation

2230

E. Allaria, L. Badano, G. De Ninno, S. Di Mitri, B. Diviacco, W.M. Fawley, N.S. Mirian, G. Penco, P. Rebernik Ribič, S. Spampinati, C. Spezzani, M. Trovò
Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Italy
G. De Ninno
University of Nova Gorica, Nova Gorica, Slovenia
E. Ferrari, E. Prat
PSI, Villigen PSI, Switzerland
D. Garzella
CEA, Gif-sur-Yvette, France
V. Grattoni
DESY, Hamburg, Germany
E. Hemsing
SLAC, Menlo Park, California, USA
M.A. Pop
MAX IV Laboratory, Lund University, Lund, Sweden
E. Roussel
PhLAM/CERLA, Villeneuve d’Ascq, France
D. Xiang
Shanghai Jiao Tong University, Shanghai, People’s Republic of China

We report the first evidence of substantial gain in a soft-X ray Free Electron Laser (FEL) based on Echo-Enabled Harmonic Generation (EEHG). The experiment was focused on harmonics 36 (~7.3nm) and 45 (5.8 nm) and clearly demonstrated the expected EEHG capability of generating powerful and coherent FEL pulses, with strongly reduced sensitivity to electron-beam fluctuations. The experiment was carried out at FERMI, the seeded FEL user facility at Elettra-Sincrotrone Trieste.

Slides WEXXPLM1 [11.410 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-WEXXPLM1

About •

paper received ※ 17 May 2019 paper accepted ※ 23 May 2019 issue date ※ 21 June 2019

Export •

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