IPAC2018 - List of Authors (Roensch-Schulenburg, J.)

Paper	Title	Page
TUPMF076	Temporal X-ray Reconstruction Using Temporal and Spectral Measurements	1440
SUSPF010	use link to see paper's listing under its alternate paper code
	F. Christie, J. Rönsch-Schulenburg, M. Vogt DESY, Hamburg, Germany Y. Ding, Z. Huang, J. Krzywinski, A.A. Lutman, T.J. Maxwell, D.F. Ratner SLAC, Menlo Park, California, USA V. A. Jhalani CALTECH, Pasadena, California, USA
	Transverse deflecting structures (TDS) are widely used in accelerator physics to measure the longitudinal density of particle bunches. When used in combination with a dispersive section, the whole longitudinal phase space density can be imaged. At the Linac Coherent Light Source (LCLS), the installation of such a device downstream of the undulators enables the reconstruction of the X-ray temporal intensity profile by comparing longitudinal phase space distributions with lasing on and lasing off. However, the resolution of this TDS is limited to around 1 fs rms (root mean square), and therefore, in most cases, it is not possible to resolve single self-amplified spontaneous emission (SASE) spikes within one photon pulse. By combining the intensity spectrum from a high resolution photon spectrometer* and the temporal structure from the TDS, the overall resolution is enhanced, thus allowing the observation of temporal, single SASE spikes. The combined data from the spectrometer and the TDS is analyzed using an iterative algorithm to obtain the actual intensity profile. In this paper, we present the reconstruction algorithm as well as analyzed data obtained from simulations which shows the reliability of this method. Real data will be published at a later stage. Y. Ding et al., Phys. Rev. ST AB, 14, 120701, 2011. *D. Zhu et al., Appl. Phys. Lett., 101, 034103, 2012.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-TUPMF076
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TUPMF089	Possible Upgrades of FLASH –- A View from the Accelerator-Perspective	1477
	M. Vogt, B. Faatz, K. Honkavaara, J. Rönsch-Schulenburg, S. Schreiber, J. Zemella DESY, Hamburg, Germany
	Recently FLASH (Free electron LASer in Hamburg) at DESY has been granted funding for a refurbishment project covering among others the replacement of two old SRF modules, an upgrade of the injector lasers and an upgrade of parts of the electron beam diagnostics. In addition we are proposing several possible upgrades and new features for the injector and the drive linac as well as in the undulator beamlines. Here we present options which are in our opinion technically feasible and at the same time operationally manageable.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-TUPMF089
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TUPMF090	Status of the Superconducting Soft X-Ray Free-Electron Laser FLASH at DESY	1481
	M. Vogt, K. Honkavaara, M. Kuhlmann, J. Rönsch-Schulenburg, S. Schreiber, R. Treusch DESY, Hamburg, Germany
	FLASH, the free-electron laser (FEL) user facility at DESY, has delivered high brilliance VUV and soft x-ray FEL radiation for photon experiments since summer 2005. In 2014 and 2015 a second beamline, FLASH2, has been commissioned in parallel to user operation at FLASH1. FLASH's superconducting linac can produce bunch trains of up to 800 bunches within a 0.8 ms RF flat top at a repetition rate of 10 Hz. In standard operation during 2017 FLASH supplied up to 500 bunches in two bunch trains with independent fill patterns and compression schemes. Since mid 2017 initial commissioning of a third experimental beamline, accommodating the FLASHForward plasma wakefield acceleration experiment, has started. We report on the highlights of the FLASH operation in 2017/2018.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-TUPMF090
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Paper

Title

Page

TUPMF076

Temporal X-ray Reconstruction Using Temporal and Spectral Measurements

1440

SUSPF010

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

F. Christie, J. Rönsch-Schulenburg, M. Vogt
DESY, Hamburg, Germany
Y. Ding, Z. Huang, J. Krzywinski, A.A. Lutman, T.J. Maxwell, D.F. Ratner
SLAC, Menlo Park, California, USA
V. A. Jhalani
CALTECH, Pasadena, California, USA

Transverse deflecting structures (TDS) are widely used in accelerator physics to measure the longitudinal density of particle bunches. When used in combination with a dispersive section, the whole longitudinal phase space density can be imaged. At the Linac Coherent Light Source (LCLS), the installation of such a device downstream of the undulators enables the reconstruction of the X-ray temporal intensity profile by comparing longitudinal phase space distributions with lasing on and lasing off*. However, the resolution of this TDS is limited to around 1 fs rms (root mean square), and therefore, in most cases, it is not possible to resolve single self-amplified spontaneous emission (SASE) spikes within one photon pulse. By combining the intensity spectrum from a high resolution photon spectrometer** and the temporal structure from the TDS, the overall resolution is enhanced, thus allowing the observation of temporal, single SASE spikes. The combined data from the spectrometer and the TDS is analyzed using an iterative algorithm to obtain the actual intensity profile. In this paper, we present the reconstruction algorithm as well as analyzed data obtained from simulations which shows the reliability of this method. Real data will be published at a later stage.
*Y. Ding et al., Phys. Rev. ST AB, 14, 120701, 2011.
**D. Zhu et al., Appl. Phys. Lett., 101, 034103, 2012.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-TUPMF076

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

TUPMF089

Possible Upgrades of FLASH –- A View from the Accelerator-Perspective

1477

M. Vogt, B. Faatz, K. Honkavaara, J. Rönsch-Schulenburg, S. Schreiber, J. Zemella
DESY, Hamburg, Germany

Recently FLASH (Free electron LASer in Hamburg) at DESY has been granted funding for a refurbishment project covering among others the replacement of two old SRF modules, an upgrade of the injector lasers and an upgrade of parts of the electron beam diagnostics. In addition we are proposing several possible upgrades and new features for the injector and the drive linac as well as in the undulator beamlines. Here we present options which are in our opinion technically feasible and at the same time operationally manageable.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-TUPMF089

Export •

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

TUPMF090

Status of the Superconducting Soft X-Ray Free-Electron Laser FLASH at DESY

1481

M. Vogt, K. Honkavaara, M. Kuhlmann, J. Rönsch-Schulenburg, S. Schreiber, R. Treusch
DESY, Hamburg, Germany

FLASH, the free-electron laser (FEL) user facility at DESY, has delivered high brilliance VUV and soft x-ray FEL radiation for photon experiments since summer 2005. In 2014 and 2015 a second beamline, FLASH2, has been commissioned in parallel to user operation at FLASH1. FLASH's superconducting linac can produce bunch trains of up to 800 bunches within a 0.8 ms RF flat top at a repetition rate of 10 Hz. In standard operation during 2017 FLASH supplied up to 500 bunches in two bunch trains with independent fill patterns and compression schemes. Since mid 2017 initial commissioning of a third experimental beamline, accommodating the FLASHForward plasma wakefield acceleration experiment, has started. We report on the highlights of the FLASH operation in 2017/2018.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-TUPMF090

Export •

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