3rd European Advanced Accelerator Concepts Workshop

Session

WG3_Parallel

25 Sept 2017, 16:00

La Biodola, Isola d'Elba

Conveners

WG3_Parallel

• Alexej Grudiev (CERN)
• Franz Kaertner (DESY, Center for Free-Electron Laser Science, and Universität Hamburg)

WG3_Parallel

• Franz Kaertner (DESY, Center for Free-Electron Laser Science, and Universität Hamburg)
• Alexej Grudiev (CERN)

WG3_Parallel

• Alexej Grudiev (CERN)
• Franz Kaertner (DESY, Center for Free-Electron Laser Science, and Universität Hamburg)

WG3_Parallel

• Alexej Grudiev (CERN)
• Franz Kaertner (DESY, Center for Free-Electron Laser Science, and Universität Hamburg)

WG3_Parallel

• Franz Kaertner (DESY, Center for Free-Electron Laser Science, and Universität Hamburg)
• Alexej Grudiev (CERN)

WG3_Parallel

• Alexej Grudiev (CERN)
• Franz Kaertner (DESY, Center for Free-Electron Laser Science, and Universität Hamburg)

219. Wakefield Acceleration and Phase Space Manipulation at the Argonne Wakefield Accelerator Facility (AWA)

Dr Manoel Conde (Argonne National Laboratory)

25/09/2017, 16:00

WG3 - Electron Beams from Electromagnetic Structures, Including Dielectric and Laser-driven Structures

talk

The AWA facility is dedicated to the study of beam physics and the development of technology for future accelerators. Two independent electron linacs are used to study wakefield acceleration: 70MeV high charge electron bunches of up to 100nC are used to drive wakefields, which can be probed by bunches originating from the same linac or from the 15MeV linac. Recent Two-Beam-Acceleration (TBA)...

24. Dielectric wakefield R&D programme at Daresbury Laboratory

Dr Yuri Saveliev (STFC, Daresbury Lab., ASTeC)

25/09/2017, 16:30

WG3 - Electron Beams from Electromagnetic Structures, Including Dielectric and Laser-driven Structures

talk

Construction of CLARA Phase I at Daresbury Laboratory is now completed and the machine is being currently commissioned. Combined with already existing VELA beamline and recently upgraded experimental beam area, this new facility is now capable of conducting a variety of experiments including advanced accelerator concepts R&D. The beam area is further enhanced by the availability of high power...

75. Status and Objectives of the Dedicated Accelerator R&D Facility "SINBAD" at DESY

Mr Ulrich Dorda (DESY)

25/09/2017, 16:50

WG3 - Electron Beams from Electromagnetic Structures, Including Dielectric and Laser-driven Structures

talk

We present an status update on the dedicated R&D facility SINBAD which is currently under construction at DESY. The facility will host multiple independent experiments on the acceleration of ultra-short electron bunches and novel, high gradient acceleration methods. The first experiment is the ARES-experiment with a normal conducting 100MeV S-band linac at its core. We present the objectives...

220. RF injector design studies for the witness beam for a plasma-based user facility

Anna Giribono (ROMA1)

25/09/2017, 17:10

WG3 - Electron Beams from Electromagnetic Structures, Including Dielectric and Laser-driven Structures

talk

The interest in plasma-based accelerators as pilot of user facilities is growing worldwide thanks to its compactness and reduced costs. The most demanding user application, as the operation of an X-ray FEL, requires ultra-high brightness electron beams in the GeV energy range. Intense beam dynamics studies have been performed to provide a reliable working point for the EuPRAXIA injector aiming...

113. High Gradients in Dielectric Wakefield Accelerators

Dr Brendan O'Shea (SLAC National Accelerator Laboratory)

25/09/2017, 18:00

WG3 - Electron Beams from Electromagnetic Structures, Including Dielectric and Laser-driven Structures

talk

Significant advancements in Dielectric Wakefield Accelerators (DWA) have been made since the first experiments 30 years ago. For example, the accelerating gradients observed have improved beyond the GV/m level at frequencies in the terahertz regime. Such strong fields generate a change in the dielectric field, similar to a metallization, that have implications for the operation of DWA as...

205. Experimental demonstration of Ballistic Bunching with Dielectric Lined Waveguides at PITZ

Dr Francois Lemery (DESY)

25/09/2017, 18:30

WG3 - Electron Beams from Electromagnetic Structures, Including Dielectric and Laser-driven Structures

talk

We discuss a recent experiment at the PITZ facility in DESY, Zeuthen. Here an electron bunch was energy modulated from its self wake in a dielectric-lined waveguide at ~6 MeV. The relatively low energy of the beam resulted in ballistic bunching and formation of enhanced peak currents at the DLW frequency (300 GHz). We discuss the theory and experimental realization.

40. High frequency laminated metallic structures for particles radiation and acceleration

Prof. Vasili Tsakanov (CANDLE Synchrotron Research Institute)

25/09/2017, 19:10

WG3 - Electron Beams from Electromagnetic Structures, Including Dielectric and Laser-driven Structures

talk

The results of theoretical, numerical and experimental studies of two-layer metallic structures electro-dynamical properties are presented. For the low conductivity inner layer the longitudinal impedance has a narrow band resonance at high frequency when the inner layer thickness is smaller than the skin depth. The resonant frequency is determined by the tube radius and the inner layer...

237. Ultra-High Brightness Electron Beams From Very-High Field Cryogenic Radiofrequency Photocathode Sources

Prof. James Rosenzweig (UCLA)

27/09/2017, 16:00

WG3 - Electron Beams from Electromagnetic Structures, Including Dielectric and Laser-driven Structures

talk

Recent investigations of RF copper structures operated at cryogenic temperatures performed by a SLAC-UCLA collaboration have shown a dramatic increase in the maximum surface electric field, to 500 MV/m. We examine use of these fields to enable very high field cryogenic photoinjectors that can attain over an order of magnitude increase in peak electron beam brightness. We present beam dynamics...

57. n-machining, surface analysis and characterization measurements of a copper photocathode at SPARC_LAB

Jessica Scifo (LNF)

27/09/2017, 16:30

WG3 - Electron Beams from Electromagnetic Structures, Including Dielectric and Laser-driven Structures

talk

An R&D activity on Cu photocathodes is under development at the SPARC_LAB test facility in order to fully know and characterize each stage of the photocathode life and to have a complete overview of the photoemission properties of the cathodes for high brightness electron beam photoinjectors. The n-machining process presented here consists in diamond milling, afterwards blown with clean air....

192. extreme high brightness electron beam generation in a space charge regime

Luca Serafini (MI)

27/09/2017, 16:50

WG3 - Electron Beams from Electromagnetic Structures, Including Dielectric and Laser-driven Structures

talk

The generation of ultra-short, low emittance and low energy spread electron bunches is nowadays a critical requirement for accelerators in plasma wave or for femtosecond light sources. These are applications were the scientific community is strongly investing in terms of study, and money, with projects and test facility around the word. This paper describes a new longitudinal compression...

133. Performance of the prototype THz-driven electron gun for the AXSIS project.

Dr Grygorii Vashchenko (DESY)

27/09/2017, 18:00

WG3 - Electron Beams from Electromagnetic Structures, Including Dielectric and Laser-driven Structures

talk

The AXSIS project (Attosecond X-ray Science: Imaging and Spectroscopy) is aiming to develop a THz driven compact X-ray source for applications e.g. in chemistry and biology by using the ultrafast coherent diffraction imaging and spectroscopy. The key components of AXSIS are the THz driven electron gun and THz-driven dielectric loaded linear accelerator as well as an inverse Compton scattering...

169. Simulations of an hybrid and compact attosecond X-ray source based on RF and THz technologies

Dr thomas vinatier (DESY)

27/09/2017, 18:30

WG3 - Electron Beams from Electromagnetic Structures, Including Dielectric and Laser-driven Structures

talk

In this paper, we present beam dynamics simulations for a proposal of hybrid and compact attosecond X-ray source based on Inverse Compton Scattering (ICS). The layout consists of an S-band gun as electron source and a dielectric-loaded waveguide driven by a multicycle THz pulse to accelerate and longitudinally compress the bunch, which will then be used to produce attosecond X-ray pulses...

89. Simulation studies for dielectric wakefield programme on CLARA facility

Mr Thomas Pacey (Cockcroft Institute/University of Manchester)

27/09/2017, 18:50

WG3 - Electron Beams from Electromagnetic Structures, Including Dielectric and Laser-driven Structures

talk

The dielectric wakefield acceleration R&D programme has been initiated on a recently constructed CLARA (Phase I) facility at Daresbury Laboratory. The machine is capable of generating sub-ps electron bunches with up to 250pC bunch charges and ~50MeV beam energy. We present simulation results for upcoming experiments that will utilise a planar variable gap dielectric lined waveguide as a...

183. High Energy Narrowband Terahertz Generation with Broadband Chirped Pulse Trains in Periodically Poled Lithium Niobate

Spencer Jolly (Center for Free-Electron Laser Science & Department of Physics, Hamburg University, Hamburg, Germany)

27/09/2017, 19:10

WG3 - Electron Beams from Electromagnetic Structures, Including Dielectric and Laser-driven Structures

talk

We generate narrowband terahertz (THz) radiation in periodically poled lithium niobate (PPLN) crystals using chirped-and-delayed driver pulse trains from a broadband high-energy Ti:Sapphire laser. We achieve higher conversion efficiencies via cryogenic cooling, and produce multicycle THz pulses with record energies of 40 μJ at 0.544 THz and above 100 μJ at 0.361 THz using crystals with...

231. Staging, focusing and microbunching in dielectric laser accelerators

Dr Joshua McNeur (Friedrich-Alexander-University of Erlangen Nürnberg)

28/09/2017, 16:00

WG3 - Electron Beams from Electromagnetic Structures, Including Dielectric and Laser-driven Structures

talk

Dielectric laser accelerators (DLAs) form a class of novel accelerators that potentially enables a variety of exciting applications, ranging from MeV handheld electron sources to table-top coherent x-ray sources. Recently, DLAs have demonstrated acceleration gradients approaching 1 GeV/m with a variety of dielectric materials, laser wavelengths, and nanostructure geometries. Realizing the...

238. Laser-driven Dielectric Wakefield Accelerator

Prof. James Rosenzweig (UCLA)

28/09/2017, 16:20

WG3 - Electron Beams from Electromagnetic Structures, Including Dielectric and Laser-driven Structures

talk

A new concept in laser-driven high field acceleration is proposed in which a laser is used to excite, by optical rectification in a nonlinear medium, a series of resonant THz cavities. This second order process entails a mode conversion from optical-IR to THz radiation that is analogous to ponderomotive excitation of plasma waves in the laser wakefield accelerator. With a laser pulse train, it...

218. Demonstration of increased interaction length in a high gradient dielectric laser accelerator

David Cesar (UCLA-PBPL)

28/09/2017, 16:40

WG3 - Electron Beams from Electromagnetic Structures, Including Dielectric and Laser-driven Structures

talk

We will present recent observations in which a pulse front tilted laser is used to accelerate electrons along a 0.5mm dual-grating dielectric laser accelerator (DLA). The tilted pulse front provides group velocity matching of the laser to the electron beam, allowing us to take advantage of the high accelerating gradient provided by an ultrafast laser; while free space optics are used to...

2. Energy efficiency studies for dual-grating dielectric laser-driven accelerators

Mr Yelong Wei (University of Liverpool/Cockcroft Institute)

28/09/2017, 17:00

WG3 - Electron Beams from Electromagnetic Structures, Including Dielectric and Laser-driven Structures

talk

Dielectric laser-driven accelerators (DLAs) utilizing large electric field from commercial laser system to accelerate particles with high gradients in the range of GV/m have the potential to realize a first particle accelerator ‘on a chip’. Dual-grating structures are one of the candidates for DLAs. They can be mass-produced using available nanofabrication techniques due to their simpler...

59. Transfer matrix and transfer function analysis for grating-type dielectric laser accelerators

Dr Andrzej Szczepkowicz (University of Wroclaw, Institute of Experimental Physics)

28/09/2017, 17:15

WG3 - Electron Beams from Electromagnetic Structures, Including Dielectric and Laser-driven Structures

talk

The question of suitability of transfer matrix description of electrons traversing grating-type dielectric laser acceleration (DLA) structures is addressed. It is shown that although matrix considerations lead to interesting insights, the basic transfer properties of DLA cells cannot be described by a matrix. A more general notion of a transfer function is shown to be a simple and useful tool...

212. Demonstration of cascaded pre-bunching for enhanced particle trapping in an Inverse Free Electron Laser accelerator

Mr Nicholas Sudar (University of California, Los Angeles)

28/09/2017, 18:00

WG3 - Electron Beams from Electromagnetic Structures, Including Dielectric and Laser-driven Structures

talk

We present results of an experiment performed at Brookhaven National Lab's Accelerator Test Facility showing the first successful demonstration of a cascaded pre-bunching scheme. Two modulator-chicane pre-bunchers arranged in series and a high power CO2 laser seed tailor the longitudinal phase space of a 52 MeV electron beam creating a series of dense micro-bunches. Injecting this bunched beam...

115. Group and phase velocity matching in THz IFEL interaction

Emma Curry (UCLA)

28/09/2017, 18:30

WG3 - Electron Beams from Electromagnetic Structures, Including Dielectric and Laser-driven Structures

talk

We review results from the recent guided-THz IFEL experiment at the UCLA PEGASUS facility. Using a parallel plate waveguide, the group velocity of a near-single cycle THz pulse was reduced to match electron beam propagation in an undulator, resulting in a ponderomotive interaction sustained for 30 cm. With a 1 uJ THz pulse obtained by optical rectification in a LN source, the projected beam...

217. Resonnant excitation of surface plasma waves in the relativistic regime: electron bunches and high order harmonic generation

Dr Tiberio Ceccotti (CEA Saclay)

28/09/2017, 18:50

WG3 - Electron Beams from Electromagnetic Structures, Including Dielectric and Laser-driven Structures

talk

Exploiting the ultra-high contrast laser facility UHI100 in Saclay we observed the acceleration of an electron beam driven by surface plasma waves (SPW) and the generation of high order harmonic along the surface of opportunely structured targets. Our experimental results clearly show a strong enhancement of both the energy and the number of electrons emitted from such targets irradiated at an...

251. Toward a proof-of-principle experiment of Optical Stochastic Cooling

Mr Matthew Andorf (Northern Illinois University)

28/09/2017, 19:10

WG3 - Electron Beams from Electromagnetic Structures, Including Dielectric and Laser-driven Structures

talk

Owing to the superior bandwidth of amplifiers at optical wavelengths the Optical Stochastic Cooling (OSC) technique was first proposed more than 20 years ago as a radical improvement of the widely used Stochastic Cooling operating in the microwave regime. Fermilab is currently developing a proof-of-principle experiment of the OSC method using a 100-MeV electron beam circulating in the compact...