2011 Particle Accelerator Conference - Classification: Instrumentation and Controls / Tech 23: Timing and Synchronization

Paper

Title

Page

Ultra Precision Timing System for the Laser Megajoule

633

V. Drouet, M. Luttmann, M. Prat
CEA, Arpajon, France

This article presents a specific timing system designed for the Laser Megajoule project. This accuracy timing system has to deliver 64 electrical trigger signals with a very low jitter (< 5 ps rms) in order to synchronize the 240 laser pulses on the same target, in single shot mode and over 100 meter distances. After a dimensioning phase leading to the architecture of the system and the selection of components, a prototype was developed providing 8 electrical trigger signals. We expose the architecture and the excellent results achieved on this prototype regarding jitter, thermal drift and delay linearity.

MOP279

Synchronize Lasers to LCLS e^- Beam

636

G. Huang
TUB, Beijing, People's Republic of China
J.M. Byrd, L.R. Doolittle, R.B. Wilcox
LBNL, Berkeley, California, USA

Fiber based synchronization system is used in LCLS to synchronize the laser for pump probe experiment to average electron beam arrival time. Electron bunch arrival time measured by phase cavity is one of the best measurement for FEL X pulse until now. The average bunch arrival time is transmitted through electronic length stabilized fiber link to AMO and other experiment hall. The laser oscillator is phase locked to this reference signal to maintain low jitter and drift between pump and probe. The in loop error shows the jitter is less then 100 fs and meets the experiment requirement.

MOP281

ADC Clocking Formats and Matching Networks

639

A.J. Della Penna
BNL, Upton, Long Island, New York, USA

Clocking an ADC is the most critical point when resolution is a major concern. Any fluctuations on the input clock performance correlates to jitter. The many different formats used to clock ADCs on the market makes choosing the appropriate one no easy task. LVDS, PECL, LVPECL, CMOS and CML are just some of the different types. With each type a certain matching network will be required. This paper will discuss the advantages of each format as well as its associated matching network.

MOP282

A Deterministic, Gigabit Serial Timing, Synchronization and Data Link for the RHIC LLRF

642

T. Hayes, F. Severino, K.S. Smith
BNL, Upton, Long Island, New York, USA

Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
A critical capability of the new RHIC low level rf system is the ability to synchronize signals across multiple locations. The Update Link provides this functionality. The Update Link is a deterministic serial data link based on the Xilinx Aurora protocol that is broadcast over fiber optic cable at 1 gigabit per second. The link provides timing events and data packets as well as time stamp information for synchronizing diagnostic data from multiple sources.

MOP285

Synchronization and Jitter Studies of a Titanium-sapphire Laser at the A0 Photoinjector

651

T.J. Maxwell, P. Piot
Northern Illinois University, DeKalb, Illinois, USA
M.J. Kucera, J. Ruan
Fermilab, Batavia, USA

Funding: Supported by Fermi Research Alliance, LLC under U.S. Dept. of Energy Contract No. DE-AC02-07CH11359, and Northern Illinois Univ. under US Dept. of Defense DURIP program Contract N00014-08-1-1064.
A new titanium-sapphire laser has recently been installed at the A0 photoinjector for use in ongoing beam generation and ultra-fast beam diagnostics experiments. Where the system is used as the photoinjector drive laser, jitter and drift in the laser pulse time of arrival with respect to the low-level RF master oscillator and other beam components are known to degrade beam performance. These same fluctuations can also impact the temporal resolution of laser-based diagnostics. To resolve this, we present the results of some beam-based timing experiments as well as current progress on a synchronization feedback loop being adapted to the new laser system.

MOP287

Femtosecond RF Timing in Low Charge Photoinjectors

654

C.M. Scoby, R.K. Li, J.T. Moody, P. Musumeci
UCLA, Los Angeles, California, USA

Funding: Office of Naval Research Grant No. N000140711174 and US Department of Energy Grant No. DE-FG02-92ER40693.
Photoelectron gun rf parameter mapping is explored as an extension to electro-optic sampling to monitor bunch vs. laser relative time-of-arrival. The method is evaluated for timestamping sub-picocoulomb femtosecond laser-pumped dynamics in graphite via electron diffraction where the required timing resolution is < 10 fs.
*AL Cavalieri, et al. Phys. Rev. Lett. 94, 114801 (2005)
**A Azima, et al. Appl. Phys. Lett. 94, 144102 (2009)
***CM Scoby, et al. PRST-AB 13, 022801 (2010)
****KJ Kim, Rev. Nucl. Inst. Meth. A 275, 2 (1989)

WEOAN1

Accelerator Timing Systems Overview

1376

J. Serrano, P. Alvarez, M.M. Lipinski, T. Włostowski
CERN, Geneva, Switzerland

Timing systems are crucial ingredients for the successful operation of any particle accelerator complex. They are used not only to synchronize different processes but also to time-stamp and ensure overall coherency of acquired data. We describe fundamental time and frequency figures of merit and methods to measure them, and continue with a description of current synchronization solutions for different applications, precisions and geographical coverage, and some examples. Finally, we describe new trends in timing technology and applications.

Slides WEOAN1 [1.122 MB]

WEOAN2

Linac Timing, Synchronization, and Active Stabilization

1381

F. Löhl
CLASSE, Ithaca, New York, USA

Femtosecond stability is required in an increasing number of linear accelerators, especially in free-electron laser facilities, but also in future light sources based on energy-recovery linear accelerators, as well as in future linear collider projects. This paper discusses schemes to synchronize and stabilize the most critical accelerator components in order to obtain such a stability.

Slides WEOAN2 [4.441 MB]

WEOCN6

Femtosecond Resolved Determination of Electron Beam and XUV Seed Pulse Temporal Overlap in sFLASH

1452

R. Tarkeshian, A. Azima, J. Bödewadt, F. Curbis, M. Drescher, Th. Maltezopoulos, V. Miltchev, M. Mittenzwey, J. Rönsch-Schulenburg, J. Roßbach
Uni HH, Hamburg, Germany
H. Delsim-Hashemi, K. Honkavaara, H. Schlarb, S. Schreiber
DESY, Hamburg, Germany
R. Ischebeck
PSI, Villigen, Switzerland

sFLASH is a seeded experiment at the Free-Electron Laser FLASH in Hamburg. It uses a 38nm High-Harmonic-Generation (HHG) scheme to seed the FEL-process in a 10 m long variable-gap undulator. The temporal overlap between the electron and HHG pulses is critical to the seeding process. The use of a 3rd harmonic accelerating module provides a high current electron beam with ~400 fs bunch duration. The duration of the HHG laser pulse is ∼20 fs. The desired overlap is achieved in two steps. Firstly, the HHG drive laser is synchronized to the incoherent spontaneous radiation from an upstream undulator with picosecond resolution. Next, the coherent radiation from an undulator is used to determine the exact overlap of the electron beam in a modulator-radiator set-up.

Slides WEOCN6 [1.758 MB]

Paper	Title	Page
MOP278	Ultra Precision Timing System for the Laser Megajoule	633
	V. Drouet, M. Luttmann, M. Prat CEA, Arpajon, France
	This article presents a specific timing system designed for the Laser Megajoule project. This accuracy timing system has to deliver 64 electrical trigger signals with a very low jitter (< 5 ps rms) in order to synchronize the 240 laser pulses on the same target, in single shot mode and over 100 meter distances. After a dimensioning phase leading to the architecture of the system and the selection of components, a prototype was developed providing 8 electrical trigger signals. We expose the architecture and the excellent results achieved on this prototype regarding jitter, thermal drift and delay linearity.

MOP279	Synchronize Lasers to LCLS e^- Beam	636
	G. Huang TUB, Beijing, People's Republic of China J.M. Byrd, L.R. Doolittle, R.B. Wilcox LBNL, Berkeley, California, USA
	Fiber based synchronization system is used in LCLS to synchronize the laser for pump probe experiment to average electron beam arrival time. Electron bunch arrival time measured by phase cavity is one of the best measurement for FEL X pulse until now. The average bunch arrival time is transmitted through electronic length stabilized fiber link to AMO and other experiment hall. The laser oscillator is phase locked to this reference signal to maintain low jitter and drift between pump and probe. The in loop error shows the jitter is less then 100 fs and meets the experiment requirement.

MOP281	ADC Clocking Formats and Matching Networks	639
	A.J. Della Penna BNL, Upton, Long Island, New York, USA
	Clocking an ADC is the most critical point when resolution is a major concern. Any fluctuations on the input clock performance correlates to jitter. The many different formats used to clock ADCs on the market makes choosing the appropriate one no easy task. LVDS, PECL, LVPECL, CMOS and CML are just some of the different types. With each type a certain matching network will be required. This paper will discuss the advantages of each format as well as its associated matching network.

MOP282	A Deterministic, Gigabit Serial Timing, Synchronization and Data Link for the RHIC LLRF	642
	T. Hayes, F. Severino, K.S. Smith BNL, Upton, Long Island, New York, USA
	Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy. A critical capability of the new RHIC low level rf system is the ability to synchronize signals across multiple locations. The Update Link provides this functionality. The Update Link is a deterministic serial data link based on the Xilinx Aurora protocol that is broadcast over fiber optic cable at 1 gigabit per second. The link provides timing events and data packets as well as time stamp information for synchronizing diagnostic data from multiple sources.

MOP285	Synchronization and Jitter Studies of a Titanium-sapphire Laser at the A0 Photoinjector	651
	T.J. Maxwell, P. Piot Northern Illinois University, DeKalb, Illinois, USA M.J. Kucera, J. Ruan Fermilab, Batavia, USA
	Funding: Supported by Fermi Research Alliance, LLC under U.S. Dept. of Energy Contract No. DE-AC02-07CH11359, and Northern Illinois Univ. under US Dept. of Defense DURIP program Contract N00014-08-1-1064. A new titanium-sapphire laser has recently been installed at the A0 photoinjector for use in ongoing beam generation and ultra-fast beam diagnostics experiments. Where the system is used as the photoinjector drive laser, jitter and drift in the laser pulse time of arrival with respect to the low-level RF master oscillator and other beam components are known to degrade beam performance. These same fluctuations can also impact the temporal resolution of laser-based diagnostics. To resolve this, we present the results of some beam-based timing experiments as well as current progress on a synchronization feedback loop being adapted to the new laser system.

MOP287	Femtosecond RF Timing in Low Charge Photoinjectors	654
	C.M. Scoby, R.K. Li, J.T. Moody, P. Musumeci UCLA, Los Angeles, California, USA
	Funding: Office of Naval Research Grant No. N000140711174 and US Department of Energy Grant No. DE-FG02-92ER40693. Photoelectron gun rf parameter mapping is explored as an extension to electro-optic sampling to monitor bunch vs. laser relative time-of-arrival. The method is evaluated for timestamping sub-picocoulomb femtosecond laser-pumped dynamics in graphite via electron diffraction where the required timing resolution is < 10 fs. AL Cavalieri, et al. Phys. Rev. Lett. 94, 114801 (2005) A Azima, et al. Appl. Phys. Lett. 94, 144102 (2009) CM Scoby, et al. PRST-AB 13, 022801 (2010) **KJ Kim, Rev. Nucl. Inst. Meth. A 275, 2 (1989)

WEOAN1	Accelerator Timing Systems Overview	1376
	J. Serrano, P. Alvarez, M.M. Lipinski, T. Włostowski CERN, Geneva, Switzerland
	Timing systems are crucial ingredients for the successful operation of any particle accelerator complex. They are used not only to synchronize different processes but also to time-stamp and ensure overall coherency of acquired data. We describe fundamental time and frequency figures of merit and methods to measure them, and continue with a description of current synchronization solutions for different applications, precisions and geographical coverage, and some examples. Finally, we describe new trends in timing technology and applications.
	Slides WEOAN1 [1.122 MB]

WEOAN2	Linac Timing, Synchronization, and Active Stabilization	1381
	F. Löhl CLASSE, Ithaca, New York, USA
	Femtosecond stability is required in an increasing number of linear accelerators, especially in free-electron laser facilities, but also in future light sources based on energy-recovery linear accelerators, as well as in future linear collider projects. This paper discusses schemes to synchronize and stabilize the most critical accelerator components in order to obtain such a stability.
	Slides WEOAN2 [4.441 MB]

WEOCN6	Femtosecond Resolved Determination of Electron Beam and XUV Seed Pulse Temporal Overlap in sFLASH	1452
	R. Tarkeshian, A. Azima, J. Bödewadt, F. Curbis, M. Drescher, Th. Maltezopoulos, V. Miltchev, M. Mittenzwey, J. Rönsch-Schulenburg, J. Roßbach Uni HH, Hamburg, Germany H. Delsim-Hashemi, K. Honkavaara, H. Schlarb, S. Schreiber DESY, Hamburg, Germany R. Ischebeck PSI, Villigen, Switzerland
	sFLASH is a seeded experiment at the Free-Electron Laser FLASH in Hamburg. It uses a 38nm High-Harmonic-Generation (HHG) scheme to seed the FEL-process in a 10 m long variable-gap undulator. The temporal overlap between the electron and HHG pulses is critical to the seeding process. The use of a 3rd harmonic accelerating module provides a high current electron beam with ~400 fs bunch duration. The duration of the HHG laser pulse is ∼20 fs. The desired overlap is achieved in two steps. Firstly, the HHG drive laser is synchronized to the incoherent spontaneous radiation from an upstream undulator with picosecond resolution. Next, the coherent radiation from an undulator is used to determine the exact overlap of the electron beam in a modulator-radiator set-up.
	Slides WEOCN6 [1.758 MB]