IPAC2018 - List of Authors (Maxwell, T.J.)

Paper	Title	Page
TUZGBD1	Beam Instrumentation and Controls for High Repitition-rate Superconducting Linacs
	T.J. Maxwell SLAC, Menlo Park, California, USA
	The high beam rate and flexible pulse structure of the LCLS-II combined with the high brightness requirements necessitates the development of new diagnostics and a new accelerator control system. This talk summarizes the requirements, implementation challenges, and current development status of this system for LCLS-II.
	Slides TUZGBD1 [3.621 MB]
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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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THPAK153	Linac Optics Correction With Trajectory Scan Data	3606
	X. Huang, Y.-C. Chao, T.J. Maxwell SLAC, Menlo Park, California, USA T. Zhang USTC/NSRL, Hefei, Anhui, People's Republic of China
	We proposed and tested a scheme to measure and correct linac optics by scanning the beam trajectory in the horizontal and vertical phase spaces. The trajectory data are compared to tracking data in a fitting scheme, from which we can derive the quadrupole strength errors. Simulation is carried out to evaluate the requirements and the performance of the method. The method is experimentally applied to FEL linacs.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPAK153
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THPMK043	Timing Stability at LCLS	4381
	F.-J. Decker, R.N. Coffee, W.S. Colocho, J.M. Glownia, K. Gumerlock, B.L. Hill, T.J. Maxwell, J. May SLAC, Menlo Park, California, USA
	The beam stability of the LCLS (Linac Coherent Light Source) has increased substantially over the years. Transversely it is a fraction of the beam size. The energy jitter was reduced from five times the energy spread to a fraction of it. Only the timing jitter is left. It got improved during the energy jitter reduction, but typically left alone. So we have five dimensions of the six-dimensional phase space covered with feedbacks and special 60-Hz jitter setups which eliminate the difference between every other pulse, but not for the general timing setup. We describe a scheme with the RF of the XTCAV, which could be used for other setups like lasers.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPMK043
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THPMK046	Advanced Fresh-Slice Beam Manipulations for FEL X-Ray Applications	4387
	A.A. Lutman, Y. Ding, M.W. Guetg, Z. Huang, J. Krzywinski, J.P. MacArthur, A. Marinelli, T.J. Maxwell SLAC, Menlo Park, California, USA C. Emma UCLA, Los Angeles, USA
	The recent development of the Fresh-slice technique granted control on which temporal slice lases in each undulator section in an X-ray Free-electron laser. Fresh-slice has been used for several experiments at the Linac Coherent Light Source for the generation of customizable high power two-color beams, and increased the performance of self-seeding schemes. As a novel development of the technique we present the demonstration of multistage self-amplified spontaneous-emission amplification schemes for the production of high-power ultra short pulses and improved control of the temporal duration of each pulse in multi-pulse schemes.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPMK046
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Paper

Title

Page

TUZGBD1

Beam Instrumentation and Controls for High Repitition-rate Superconducting Linacs

T.J. Maxwell
SLAC, Menlo Park, California, USA

The high beam rate and flexible pulse structure of the LCLS-II combined with the high brightness requirements necessitates the development of new diagnostics and a new accelerator control system. This talk summarizes the requirements, implementation challenges, and current development status of this system for LCLS-II.

Slides TUZGBD1 [3.621 MB]

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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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THPAK153

Linac Optics Correction With Trajectory Scan Data

3606

X. Huang, Y.-C. Chao, T.J. Maxwell
SLAC, Menlo Park, California, USA
T. Zhang
USTC/NSRL, Hefei, Anhui, People's Republic of China

We proposed and tested a scheme to measure and correct linac optics by scanning the beam trajectory in the horizontal and vertical phase spaces. The trajectory data are compared to tracking data in a fitting scheme, from which we can derive the quadrupole strength errors. Simulation is carried out to evaluate the requirements and the performance of the method. The method is experimentally applied to FEL linacs.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPAK153

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

THPMK043

Timing Stability at LCLS

4381

F.-J. Decker, R.N. Coffee, W.S. Colocho, J.M. Glownia, K. Gumerlock, B.L. Hill, T.J. Maxwell, J. May
SLAC, Menlo Park, California, USA

The beam stability of the LCLS (Linac Coherent Light Source) has increased substantially over the years. Transversely it is a fraction of the beam size. The energy jitter was reduced from five times the energy spread to a fraction of it. Only the timing jitter is left. It got improved during the energy jitter reduction, but typically left alone. So we have five dimensions of the six-dimensional phase space covered with feedbacks and special 60-Hz jitter setups which eliminate the difference between every other pulse, but not for the general timing setup. We describe a scheme with the RF of the XTCAV, which could be used for other setups like lasers.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPMK043

Export •

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

THPMK046

Advanced Fresh-Slice Beam Manipulations for FEL X-Ray Applications

4387

A.A. Lutman, Y. Ding, M.W. Guetg, Z. Huang, J. Krzywinski, J.P. MacArthur, A. Marinelli, T.J. Maxwell
SLAC, Menlo Park, California, USA
C. Emma
UCLA, Los Angeles, USA

The recent development of the Fresh-slice technique granted control on which temporal slice lases in each undulator section in an X-ray Free-electron laser. Fresh-slice has been used for several experiments at the Linac Coherent Light Source for the generation of customizable high power two-color beams, and increased the performance of self-seeding schemes. As a novel development of the technique we present the demonstration of multistage self-amplified spontaneous-emission amplification schemes for the production of high-power ultra short pulses and improved control of the temporal duration of each pulse in multi-pulse schemes.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPMK046

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