IPAC2016 - Classification: 03 Alternative Particle Sources and Acceleration Techniques / A15 New Acceleration Techniques

Paper	Title	Page
TUPMY015	Ultrafast Electron Guns for the Efficient Acceleration using Single-Cycle THz Pulses	1578
	A. Fallahi, F.X. Kärtner, A. Yahaghi CFEL, Hamburg, Germany M. Fakhari DESY, Hamburg, Germany
	Funding: European Research Council (ERC) Over the past decades, advances in ultrafast technologies led to the production of intense ultrashort THz to optical pulses reaching single-cycle pulse duration. Using such pulses for electron acceleration offers advantages in terms of higher thresholds for materials breakdown, thus introducing a promising path towards increasing acceleration gradients. Conventional accelerator technology is based on either continuous wave or long pulse operation, where resonant or guiding structures are usually employed. We introduce novel structures for electron acceleration which operate with single-cycle pulses named as single-cycle ultrafast guns. The operating frequencies considered here are at THz wavelengths inspired by the recent progress in the optical generation of intense single-cycle THz pulses. We begin with designing guns for low energy pulses and proceed with structures designed for high energy pulses. More importantly, it is shown that the already achieved THz pulse energies of 20 uJ are enough to realize relativistic fields for electron acceleration. These structures will underpin future devices for fabricating miniaturized electron guns and linear accelerators.
Export •	reference for this paper to ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPMY016	Design of a Collection and Selection System for High Energy Laser-driven Ion Beams	1581
	F. Schillaci, L. Allegra, A. Amato, L. Andò, G.A.P. Cirrone, M. Costa, G. Cuttone, G. De Luca, G. Gallo, J. Pipek, F. Romano INFN/LNS, Catania, Italy G. Korn, D. Margarone, V. Scuderi ELI-BEAMS, Prague, Czech Republic M. Maggiore INFN/LNL, Legnaro (PD), Italy
	Funding: ELI-Beamlines Contract n.S14-187, LaserGen(CZ.1.07/2.3.00/30.0057), Ministry of Education of Czech Rep.(reg. No.CZ.1.05/1.1.00/02.0061), the FZU, AVCR, v.v.i and the project financed by ESF and Czech Rep. Laser-target acceleration represents a very promising alternative to conventional accelerators for several potential applications, from the nuclear physics to the medical ones. However, some extreme features, not suitable for multidisciplinary applications, as the wide energy and angular spreads are typical of optically accelerated ion beams. Therefore, beyond the improvements at the laser-target interaction level, a lot of efforts have been recently devoted to the development of specific beam-transport devices in order to obtain controlled and reproducible output beams. In this framework, a three years contract has been signed between INFN-LNS (IT) and Eli-Beamlines-IoP (CZ) to provide the design and the realization of a complete transport beam-line, named ELIMED, dedicated to the transport, diagnostics and dosimetry of laser-driven ion beams. The transport devices will be composed by a set of super-strong permanent magnet quadrupoles able to collect and focus laser driven ions up to 70MeV/u, and a magnetic chicane made of conventional electromagnetic dipole to select particles within a narrow energy range. Here, the design and development of these magnetic systems is described.
Export •	reference for this paper to ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPMY017	Laser Driven Dielectric Accelerator in the Non-relativistic Energy Region	1585
	K. Koyama, M. Uesaka The University of Tokyo, Nuclear Professional School, Ibaraki-ken, Japan S. Kurimura NIMS, Ibaraki, Japan H. Okamoto, S. Otsuki The University of Tokyo, Tokyo, Japan M. Yoshida KEK, Ibaraki, Japan
	Laser-driven dielectric accelerator (LDA) is suitable for delivering a submicron-size ultra-short electron beam, which is useful for studying basic processes of the radiation effect in a biological cell. Both the oblique incidence and the normal incidence configurations of LDA were studied. The oblique incidence configuration of LDA relaxes the synchronization condition as v_e=¥pm c L_G/¥left(¥λ+ L_G n ¥sin ¥theta ¥right) and is somewhat suitable for accelerating the non-relativistic electrons. The required energy to accelerate electrons in the oblique incidence configuration is smaller than that in the normal incidence configuration by a factor of ¥cos ¥theta, where ¥theta is the incidence angle of the laser beam. Two gratings each were made of different material structure of silica ({¥rm SiO₂}) were fabricated by the electron beam lithography. When a crystal silica was adopted, many large humps of several hundred nm size were observed in grooves of the grating. On the other hand, a glass silica had smoother grooves.
Export •	reference for this paper to ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPMY018	Recent Progress of Proton Acceleration at Peking University	1588
SUPSS027	use link to see paper's listing under its alternate paper code
	Q. Liao, Y.X. Geng, C. Lin, H.Y. Lu, W.J. Ma, X.Q. Yan, Y.Y. Zhao PKU, Beijing, People's Republic of China
	We study the enhanced laser ion acceleration using near critical density plasma lens attached to the front of a solid target. The laser quality is spontaneously improved by the plasma lens and energy density of hot electrons is greatly increased by the direct laser acceleration mechanism. Both factors will induce stronger sheath electric field at the rear surface of the target, which accelerates ions to a higher energy. Particle-in-cell simulations show that proton energy can be increased 2-3 times compared with single solid target. This result provides the opportunities for applications of laser plasma accelerator, such as cancer therapy. Further experiments will soon be carried out on 200 TW laser acceleration system at Peking University.
Export •	reference for this paper to ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPMY019	CLAPA Proton Beam Line in Peking University	1592
SUPSS028	use link to see paper's listing under its alternate paper code
	J.G. Zhu, J.E. Chen, C. Lin, H.Y. Lu, W.J. Ma, L. Tao, X.Q. Yan, K. Zhu PKU, Beijing, People's Republic of China
	Comparing with the conventional accelerator, the laser plasma accelerator can accelerate ions more effectively and greatly reduce the scale and cost. A laser accelerator− Compact Laser Plasma Accelerator (CLAPA) is being built at Institute of Heavy Ion physics of Peking University. According to the beam parameters from proof of principle experiments and theoretical simulations, we design the beam line for ions transport which is being built now and in the near future we will carry out experimental study with it. The beam line is mainly constituted by quadrupole and analyzing magnets . The quadrupole triplet lens collects protons generated from the target, while the analyzing magnet system will choose the protons with proper energy. The transport is simulated by program TRACK. The beam line is designed to deliver proton beam with the energy of 1~ 40MeV, energy spread of ±1% and 106-8 protons per pulse to satisfy the requirement of different experiments. The transmission efficiency is about 94% when the energy spread is ±1%.
Export •	reference for this paper to ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPMY023	Advanced Gabor Lens Lattice for Laser Driven Hadron Therapy and Other Applications	1595
	J.K. Pozimski, M. Aslaninejad, P.A. Posocco Imperial College of Science and Technology, Department of Physics, London, United Kingdom
	Funding: Funding was provided by the Imperial Confidence in Concept scheme. The application of laser accelerated ion beams in hadron therapy requires a beam optics with unique features. Due to the spectral and spatial distribution of laser accelerated protons a compact ion optical system with therapy applications, based on Gabor space charge lenses for collecting, focusing and energy filtering the laser produced proton beam, has significant advantages compared with other setups. While a passive momentum selection could improve already the usability of laser driven hadron, we show that an advanced lattice utilizing additional RF cavities not only will deliver a momentum spread smaller than conventional accelerators, but also will increases the dose delivered. Furthermore, a possible near term application in the field of radio nuclide production is presented.
Export •	reference for this paper to ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPMY024	First Test of The Imperial College Gabor (Plasma) Lens prototype at the Surrey Ion Beam centre	1598
	P.A. Posocco, J.K. Pozimski, Y. Xia Imperial College of Science and Technology, Department of Physics, London, United Kingdom M.J. Merchant UoM ICS, Manchester, United Kingdom M.J. Merchant The Christie NHS Foundation Trust, Manchester, United Kingdom
	Funding: Funding was provided by the Imperial College Confidence in Concepts scheme. The first plasma (Gabor) lens prototype operating at high electron density was built by the Imperial College London in 2015. In November 2015 the lens was tested at the Ion Beam Centre of the University of Surrey with a 1 MeV proton beam. Over 500 snapshots of the beam hitting a scintillator screen installed 0.5 m downstream of the lens were taken for a wide range of settings. Unexpectedly, instead of over- or underfocusing the incoming particles, the lens converted pencil beams into rings. In addition to the dependence of their radius on the lens settings, periodic features appeared along the circumference, suggesting that the electron plasma was exited into a coherent off-axis rotation. The cause of this phenomenon is under investigation.
Export •	reference for this paper to ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPMY025	Proton-Driven Electron Acceleration in Hollow Plasma	1601
	Y. M. Li, K. Hanahoe, O. Mete Apsimon, T.H. Pacey, G.X. Xia UMAN, Manchester, United Kingdom
	Funding: President's Doctoral Scholar Award from The University of Manchester. Proton driven plasma wakefield acceleration has been proposed to accelerate electrons to TeV-scale in a single hundreds of meters plasma section. However, it is difficult to conserve beam quality due to the positively charged driven scheme. In this paper, we demonstrate via simulation that hollow plasma is favourable to maintain the long and stable acceleration and simultaneously be able to achieve low normalized emittance and energy spread of the witness electrons. Moreover, it has much higher beam loading tolerance compared to the uniform case. This will potentially facilitates the acceleration of a large number of particles with high beam quality. * Caldwell A et al.Nature Physics, 2009, 5(5): 363-367 K. Lotov, Phys. Rev. ST Accel. Beams, 2010, 13(4): 041301. * W. Kimura et al., Phys. Rev. ST Accel. Beams, 2011, 14(4): 041301.
Export •	reference for this paper to ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPMY026	Electron Beam Generation and Injection From a Pyroelectric Crystal Array	1604
	R.B. Yoder, Z. Kabilova, B. Saeks Goucher College, Baltimore, Maryland, USA
	Novel acceleration structures (e.g. dielectric laser accelerators [DLAs]) powered by lasers have the potential to greatly reduce the footprint and cost of both industrial linacs and colliders. As these devices have dimensions comparable to optical wavelengths, they require injection of a sub-micron-scale electron bunch to generate high-quality output beams, which are well beyond the capability of conventional rf photocathodes. Photoexcitation and field emission from an array of nanotips, followed by further acceleration and focusing, is a promising approach to achieving the requisite small beam sizes for successful injection. Pyroelectric crystals can provide electrostatic fields of sufficient magnitude and uniformity to enable emission and acceleration. We present an initial design for a low-energy injection module using the accelerating electrostatic fields provided by pyroelectric crystals. The approach is modeled numerically and supported by direct benchtop measurements of pyroelectric fields from a 2-crystal array. R. J. England et al., Rev. Mod. Phys. 86, p. 1337 (2014).
Export •	reference for this paper to ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPMY028	Ultra-high Gradient Acceleration in Nano-crystal Channels	1607
	Y.-M. Shin Northern Illinois University, DeKalb, Illinois, USA D.M. Farinella, P. Taborek, T. Tajima UCI, Irvine, California, USA A.H. Lumpkin, V.D. Shiltsev, R.M. Thurman-Keup Fermilab, Batavia, Illinois, USA X. Zhang Shanghai Institute of Optics and Fine Mechanics, Shanghai, People's Republic of China
	Funding: This work was supported by the DOE contract No.DEAC02-07CH11359 to the Fermi Research Alliance LLC. We also thank the FAST Department team for the helpful discussions and technical support. Crystals behave like a non-equilibrium medium (e.g. plasma), but at a relatively low temperature, if heated by a high-power driving source. The warm dense matter contains many more ions (n0 ~ 10¹⁹ - 10²³ cm^-3) available for plasma acceleration than gaseous plasmas, and can possibly support electric fields of up to 30 TV/m of plasma oscillation,,,. Atomic lattice spaces in solid crystals are known to consist of 10 - 100 V/Å potential barriers capable of guiding and collimating high energy particles with continuously focused acceleration. Nanostructured crystals (e.g. carbon nanotube) with dimensional flexibilities can accept a few orders of magnitude larger phase-space volume of channeled particles than natural crystals. Our PIC simulation results*, **** obtained from two plasma acceleration codes, VORPAL and EPOCH, indicate that in the linear regime the beam-driven and laser-driven electrons channeled in a 100 micro-meter long effective nanotube gain 10 MeV (G = 1 - 10 TeV/m). Experimental tests, including slit-mask beam modulation and pump-probe electron diffraction, are designed in Fermilab and NIU to identify a wakefield effect in a photo-excited crystal. * Phys. Rev.Lett. 43, 267(1979) Phys. Plasmas 15, 103105(2008) * Nature Photonics 9, 274(2015) ** Phys. J. 223, 1037(2014) * Appl. Phys. Lett. 105, 114106(2014) **** Phys. Plasmas 20, 123106(2013)
Export •	reference for this paper to ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOY024	Wave Particle Cherenkov Interactions Mediated via Novel Materials	1960
	A. Hopper IIAA, Huddersfield, United Kingdom R. Seviour University of Huddersfield, Huddersfield, United Kingdom
	Currently there is an increasing interest in dielectric wall accelerators. These work by slowing the speed of an EM wave to match the velocity of a particle beam, allowing wave-beam interactions, accelerating the beam. However conventional dielectric materials have limited interaction regions, so wave-beam energy transfer is minimal. In this paper we consider Artificial Materials (AMs), as slow wave structures, in the presence of charged particle beams to engineer Inverse-Cherenkov acceleration. AMs are periodic constructs whose properties depend on their subwavelength geometry rather than their material composition, and can be engineered to give an arbitrary dispersion relation. We show that Metamaterials, one example of an AM, can mediate an Inverse-Cherenkov interaction, but break down in high power environments due to high absorption. We consider AMs with low constitutive parameters and show they can exhibit low absorption whilst maintaining the ability to have a user defined dispersion relation, and mediate a wavebeam interaction leading to Inverse-Cherenkov acceleration.
Export •	reference for this paper to ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOY027	Beam Dynamics Studies into Grating-based Dielectric Laser-driven Accelerators	1970
	Y. Wei, S.P. Jamison, C.P. Welsch Cockcroft Institute, Warrington, Cheshire, United Kingdom K. Hanahoe, Y. M. Li, G.X. Xia UMAN, Manchester, United Kingdom S.P. Jamison STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom J.D.A. Smith TXUK, Warrington, United Kingdom Y. Wei, C.P. Welsch The University of Liverpool, Liverpool, United Kingdom
	Funding: Work supported by the EU under grant agreement 289191 and the STFC under the Cockcroft Institute core grant ST/G008248/1. Dielectric laser-driven accelerators (DLAs) based on gratings confine an electromagnetic field induced by a drive laser into a narrow vacuum channel where electrons travel and are accelerated. This can provide an alternative acceleration technology compared to conventional rf cavity accelerators. Due to the achievable high acceleration gradient of up to several GV/m this could pave the way for future ultra-short and low costμaccelerators. This contribution presents detailed beam dynamics simulations for multi-period double grating structures. Using the computer code VSim and realistic beam distributions, the achievable acceleration gradient and final beam quality in terms of emittance and energy spread are discussed. The results are then used for an overall optimization of the accelerating structure.
Export •	reference for this paper to ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEXB01	Status, Plans and Potential Applications of the ELIMED Beam Line at ELI-Beamlines	2077
	G.A.P. Cirrone, L. Allegra, A. Amato, A. Amico, G. Candiano, A.C. Caruso, L. Cosentino, M. Costa, G. Cuttone, G. De Luca, G. Gallo, S. Gammino, G. Larosa, R. Leanza, R. Manna, V. Marchese, G. Milluzzo, G. Petringa, J. Pipek, P.S. Pulvirenti, F. Romano, S. Salamone, F. Schillaci, V. Scuderi INFN/LNS, Catania, Italy G. Korn, D. Margarone, V. Scuderi ELI-BEAMS, Prague, Czech Republic
	Charged particle acceleration using ultra-intense and ultra-short laser pulses has gathered a strong interest in the scientific community and it is now one of the most attractive topics in the relativistic laser-plasma interaction research. Indeed, it could represent the future of particle acceleration and open new scenarios in multidisciplinary fields, in particular, medical applications. One of the biggest challenges consists of using, in a future perspective, high intensity laser-target interaction to generate high-energy ions for therapeutic purposes, eventually replacing the old paradigm of acceleration, characterized by huge and complex machines. In this framework, INFN-LNS (Italian Institute of Nuclear Physics, Catania (I)) in collaboration with ELI-Beamline Institute (Dolny Brezany, CZ) will realise, within 2017 the ELIMED (ELI-Beamlines MEDical and multidisciplinary applications) beamline. ELIMED will be the first Users' addressed transport beamline dedicated to the medical and multidisciplinary studies with laser-accelerated ion beams.
	Slides WEXB01 [29.683 MB]
Export •	reference for this paper to ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Ultrafast Electron Guns for the Efficient Acceleration using Single-Cycle THz Pulses

1578

A. Fallahi, F.X. Kärtner, A. Yahaghi
CFEL, Hamburg, Germany
M. Fakhari
DESY, Hamburg, Germany

Funding: European Research Council (ERC)
Over the past decades, advances in ultrafast technologies led to the production of intense ultrashort THz to optical pulses reaching single-cycle pulse duration. Using such pulses for electron acceleration offers advantages in terms of higher thresholds for materials breakdown, thus introducing a promising path towards increasing acceleration gradients. Conventional accelerator technology is based on either continuous wave or long pulse operation, where resonant or guiding structures are usually employed. We introduce novel structures for electron acceleration which operate with single-cycle pulses named as single-cycle ultrafast guns. The operating frequencies considered here are at THz wavelengths inspired by the recent progress in the optical generation of intense single-cycle THz pulses. We begin with designing guns for low energy pulses and proceed with structures designed for high energy pulses. More importantly, it is shown that the already achieved THz pulse energies of 20 uJ are enough to realize relativistic fields for electron acceleration. These structures will underpin future devices for fabricating miniaturized electron guns and linear accelerators.

Export •

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

TUPMY016

Design of a Collection and Selection System for High Energy Laser-driven Ion Beams

1581

F. Schillaci, L. Allegra, A. Amato, L. Andò, G.A.P. Cirrone, M. Costa, G. Cuttone, G. De Luca, G. Gallo, J. Pipek, F. Romano
INFN/LNS, Catania, Italy
G. Korn, D. Margarone, V. Scuderi
ELI-BEAMS, Prague, Czech Republic
M. Maggiore
INFN/LNL, Legnaro (PD), Italy

Funding: ELI-Beamlines Contract n.S14-187, LaserGen(CZ.1.07/2.3.00/30.0057), Ministry of Education of Czech Rep.(reg. No.CZ.1.05/1.1.00/02.0061), the FZU, AVCR, v.v.i and the project financed by ESF and Czech Rep.
Laser-target acceleration represents a very promising alternative to conventional accelerators for several potential applications, from the nuclear physics to the medical ones. However, some extreme features, not suitable for multidisciplinary applications, as the wide energy and angular spreads are typical of optically accelerated ion beams. Therefore, beyond the improvements at the laser-target interaction level, a lot of efforts have been recently devoted to the development of specific beam-transport devices in order to obtain controlled and reproducible output beams. In this framework, a three years contract has been signed between INFN-LNS (IT) and Eli-Beamlines-IoP (CZ) to provide the design and the realization of a complete transport beam-line, named ELIMED, dedicated to the transport, diagnostics and dosimetry of laser-driven ion beams. The transport devices will be composed by a set of super-strong permanent magnet quadrupoles able to collect and focus laser driven ions up to 70MeV/u, and a magnetic chicane made of conventional electromagnetic dipole to select particles within a narrow energy range. Here, the design and development of these magnetic systems is described.

Export •

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

TUPMY017

Laser Driven Dielectric Accelerator in the Non-relativistic Energy Region

1585

K. Koyama, M. Uesaka
The University of Tokyo, Nuclear Professional School, Ibaraki-ken, Japan
S. Kurimura
NIMS, Ibaraki, Japan
H. Okamoto, S. Otsuki
The University of Tokyo, Tokyo, Japan
M. Yoshida
KEK, Ibaraki, Japan

Laser-driven dielectric accelerator (LDA) is suitable for delivering a submicron-size ultra-short electron beam, which is useful for studying basic processes of the radiation effect in a biological cell. Both the oblique incidence and the normal incidence configurations of LDA were studied. The oblique incidence configuration of LDA relaxes the synchronization condition as v_e=¥pm c L_G/¥left(¥λ+ L_G n ¥sin ¥theta ¥right) and is somewhat suitable for accelerating the non-relativistic electrons. The required energy to accelerate electrons in the oblique incidence configuration is smaller than that in the normal incidence configuration by a factor of ¥cos ¥theta, where ¥theta is the incidence angle of the laser beam. Two gratings each were made of different material structure of silica ({¥rm SiO₂}) were fabricated by the electron beam lithography. When a crystal silica was adopted, many large humps of several hundred nm size were observed in grooves of the grating. On the other hand, a glass silica had smoother grooves.

Export •

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

TUPMY018

Recent Progress of Proton Acceleration at Peking University

1588

SUPSS027

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

Q. Liao, Y.X. Geng, C. Lin, H.Y. Lu, W.J. Ma, X.Q. Yan, Y.Y. Zhao
PKU, Beijing, People's Republic of China

We study the enhanced laser ion acceleration using near critical density plasma lens attached to the front of a solid target. The laser quality is spontaneously improved by the plasma lens and energy density of hot electrons is greatly increased by the direct laser acceleration mechanism. Both factors will induce stronger sheath electric field at the rear surface of the target, which accelerates ions to a higher energy. Particle-in-cell simulations show that proton energy can be increased 2-3 times compared with single solid target. This result provides the opportunities for applications of laser plasma accelerator, such as cancer therapy. Further experiments will soon be carried out on 200 TW laser acceleration system at Peking University.

Export •

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

TUPMY019

CLAPA Proton Beam Line in Peking University

1592

SUPSS028

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

J.G. Zhu, J.E. Chen, C. Lin, H.Y. Lu, W.J. Ma, L. Tao, X.Q. Yan, K. Zhu
PKU, Beijing, People's Republic of China

Comparing with the conventional accelerator, the laser plasma accelerator can accelerate ions more effectively and greatly reduce the scale and cost. A laser accelerator− Compact Laser Plasma Accelerator (CLAPA) is being built at Institute of Heavy Ion physics of Peking University. According to the beam parameters from proof of principle experiments and theoretical simulations, we design the beam line for ions transport which is being built now and in the near future we will carry out experimental study with it. The beam line is mainly constituted by quadrupole and analyzing magnets . The quadrupole triplet lens collects protons generated from the target, while the analyzing magnet system will choose the protons with proper energy. The transport is simulated by program TRACK. The beam line is designed to deliver proton beam with the energy of 1~ 40MeV, energy spread of ±1% and 106-8 protons per pulse to satisfy the requirement of different experiments. The transmission efficiency is about 94% when the energy spread is ±1%.

Export •

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

TUPMY023

Advanced Gabor Lens Lattice for Laser Driven Hadron Therapy and Other Applications

1595

J.K. Pozimski, M. Aslaninejad, P.A. Posocco
Imperial College of Science and Technology, Department of Physics, London, United Kingdom

Funding: Funding was provided by the Imperial Confidence in Concept scheme.
The application of laser accelerated ion beams in hadron therapy requires a beam optics with unique features. Due to the spectral and spatial distribution of laser accelerated protons a compact ion optical system with therapy applications, based on Gabor space charge lenses for collecting, focusing and energy filtering the laser produced proton beam, has significant advantages compared with other setups. While a passive momentum selection could improve already the usability of laser driven hadron, we show that an advanced lattice utilizing additional RF cavities not only will deliver a momentum spread smaller than conventional accelerators, but also will increases the dose delivered. Furthermore, a possible near term application in the field of radio nuclide production is presented.

Export •

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

TUPMY024

First Test of The Imperial College Gabor (Plasma) Lens prototype at the Surrey Ion Beam centre

1598

P.A. Posocco, J.K. Pozimski, Y. Xia
Imperial College of Science and Technology, Department of Physics, London, United Kingdom
M.J. Merchant
UoM ICS, Manchester, United Kingdom
M.J. Merchant
The Christie NHS Foundation Trust, Manchester, United Kingdom

Funding: Funding was provided by the Imperial College Confidence in Concepts scheme.
The first plasma (Gabor) lens prototype operating at high electron density was built by the Imperial College London in 2015. In November 2015 the lens was tested at the Ion Beam Centre of the University of Surrey with a 1 MeV proton beam. Over 500 snapshots of the beam hitting a scintillator screen installed 0.5 m downstream of the lens were taken for a wide range of settings. Unexpectedly, instead of over- or underfocusing the incoming particles, the lens converted pencil beams into rings. In addition to the dependence of their radius on the lens settings, periodic features appeared along the circumference, suggesting that the electron plasma was exited into a coherent off-axis rotation. The cause of this phenomenon is under investigation.

Export •

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

TUPMY025

Proton-Driven Electron Acceleration in Hollow Plasma

1601

Y. M. Li, K. Hanahoe, O. Mete Apsimon, T.H. Pacey, G.X. Xia
UMAN, Manchester, United Kingdom

Funding: President's Doctoral Scholar Award from The University of Manchester.
Proton driven plasma wakefield acceleration has been proposed to accelerate electrons to TeV-scale in a single hundreds of meters plasma section. However, it is difficult to conserve beam quality due to the positively charged driven scheme. In this paper, we demonstrate via simulation that hollow plasma is favourable to maintain the long and stable acceleration and simultaneously be able to achieve low normalized emittance and energy spread of the witness electrons. Moreover, it has much higher beam loading tolerance compared to the uniform case. This will potentially facilitates the acceleration of a large number of particles with high beam quality.
* Caldwell A et al.Nature Physics, 2009, 5(5): 363-367
** K. Lotov, Phys. Rev. ST Accel. Beams, 2010, 13(4): 041301.
*** W. Kimura et al., Phys. Rev. ST Accel. Beams, 2011, 14(4): 041301.

Export •

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

TUPMY026

Electron Beam Generation and Injection From a Pyroelectric Crystal Array

1604

R.B. Yoder, Z. Kabilova, B. Saeks
Goucher College, Baltimore, Maryland, USA

Novel acceleration structures (e.g. dielectric laser accelerators [DLAs]*) powered by lasers have the potential to greatly reduce the footprint and cost of both industrial linacs and colliders. As these devices have dimensions comparable to optical wavelengths, they require injection of a sub-micron-scale electron bunch to generate high-quality output beams, which are well beyond the capability of conventional rf photocathodes. Photoexcitation and field emission from an array of nanotips, followed by further acceleration and focusing, is a promising approach to achieving the requisite small beam sizes for successful injection. Pyroelectric crystals can provide electrostatic fields of sufficient magnitude and uniformity to enable emission and acceleration. We present an initial design for a low-energy injection module using the accelerating electrostatic fields provided by pyroelectric crystals. The approach is modeled numerically and supported by direct benchtop measurements of pyroelectric fields from a 2-crystal array.
*R. J. England et al., Rev. Mod. Phys. 86, p. 1337 (2014).

Export •

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

TUPMY028

Ultra-high Gradient Acceleration in Nano-crystal Channels

1607

Y.-M. Shin
Northern Illinois University, DeKalb, Illinois, USA
D.M. Farinella, P. Taborek, T. Tajima
UCI, Irvine, California, USA
A.H. Lumpkin, V.D. Shiltsev, R.M. Thurman-Keup
Fermilab, Batavia, Illinois, USA
X. Zhang
Shanghai Institute of Optics and Fine Mechanics, Shanghai, People's Republic of China

Funding: This work was supported by the DOE contract No.DEAC02-07CH11359 to the Fermi Research Alliance LLC. We also thank the FAST Department team for the helpful discussions and technical support.
Crystals behave like a non-equilibrium medium (e.g. plasma), but at a relatively low temperature, if heated by a high-power driving source. The warm dense matter contains many more ions (n0 ~ 10¹⁹ - 10²³ cm^-3) available for plasma acceleration than gaseous plasmas, and can possibly support electric fields of up to 30 TV/m of plasma oscillation*,**,***,****. Atomic lattice spaces in solid crystals are known to consist of 10 - 100 V/Å potential barriers capable of guiding and collimating high energy particles with continuously focused acceleration. Nanostructured crystals (e.g. carbon nanotube) with dimensional flexibilities can accept a few orders of magnitude larger phase-space volume of channeled particles than natural crystals. Our PIC simulation results*****, ****** obtained from two plasma acceleration codes, VORPAL and EPOCH, indicate that in the linear regime the beam-driven and laser-driven electrons channeled in a 100 micro-meter long effective nanotube gain 10 MeV (G = 1 - 10 TeV/m). Experimental tests, including slit-mask beam modulation and pump-probe electron diffraction, are designed in Fermilab and NIU to identify a wakefield effect in a photo-excited crystal.
* Phys. Rev.Lett. 43, 267(1979)
** Phys. Plasmas 15, 103105(2008)
*** Nature Photonics 9, 274(2015)
**** Phys. J. 223, 1037(2014)
***** Appl. Phys. Lett. 105, 114106(2014)
****** Phys. Plasmas 20, 123106(2013)

Export •

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

TUPOY024

Wave Particle Cherenkov Interactions Mediated via Novel Materials

1960

A. Hopper
IIAA, Huddersfield, United Kingdom
R. Seviour
University of Huddersfield, Huddersfield, United Kingdom

Currently there is an increasing interest in dielectric wall accelerators. These work by slowing the speed of an EM wave to match the velocity of a particle beam, allowing wave-beam interactions, accelerating the beam. However conventional dielectric materials have limited interaction regions, so wave-beam energy transfer is minimal. In this paper we consider Artificial Materials (AMs), as slow wave structures, in the presence of charged particle beams to engineer Inverse-Cherenkov acceleration. AMs are periodic constructs whose properties depend on their subwavelength geometry rather than their material composition, and can be engineered to give an arbitrary dispersion relation. We show that Metamaterials, one example of an AM, can mediate an Inverse-Cherenkov interaction, but break down in high power environments due to high absorption. We consider AMs with low constitutive parameters and show they can exhibit low absorption whilst maintaining the ability to have a user defined dispersion relation, and mediate a wavebeam interaction leading to Inverse-Cherenkov acceleration.

Export •

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

TUPOY027

Beam Dynamics Studies into Grating-based Dielectric Laser-driven Accelerators

1970

Y. Wei, S.P. Jamison, C.P. Welsch
Cockcroft Institute, Warrington, Cheshire, United Kingdom
K. Hanahoe, Y. M. Li, G.X. Xia
UMAN, Manchester, United Kingdom
S.P. Jamison
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
J.D.A. Smith
TXUK, Warrington, United Kingdom
Y. Wei, C.P. Welsch
The University of Liverpool, Liverpool, United Kingdom

Funding: Work supported by the EU under grant agreement 289191 and the STFC under the Cockcroft Institute core grant ST/G008248/1.
Dielectric laser-driven accelerators (DLAs) based on gratings confine an electromagnetic field induced by a drive laser into a narrow vacuum channel where electrons travel and are accelerated. This can provide an alternative acceleration technology compared to conventional rf cavity accelerators. Due to the achievable high acceleration gradient of up to several GV/m this could pave the way for future ultra-short and low costμaccelerators. This contribution presents detailed beam dynamics simulations for multi-period double grating structures. Using the computer code VSim and realistic beam distributions, the achievable acceleration gradient and final beam quality in terms of emittance and energy spread are discussed. The results are then used for an overall optimization of the accelerating structure.

Export •

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

WEXB01

Status, Plans and Potential Applications of the ELIMED Beam Line at ELI-Beamlines

2077

G.A.P. Cirrone, L. Allegra, A. Amato, A. Amico, G. Candiano, A.C. Caruso, L. Cosentino, M. Costa, G. Cuttone, G. De Luca, G. Gallo, S. Gammino, G. Larosa, R. Leanza, R. Manna, V. Marchese, G. Milluzzo, G. Petringa, J. Pipek, P.S. Pulvirenti, F. Romano, S. Salamone, F. Schillaci, V. Scuderi
INFN/LNS, Catania, Italy
G. Korn, D. Margarone, V. Scuderi
ELI-BEAMS, Prague, Czech Republic

Charged particle acceleration using ultra-intense and ultra-short laser pulses has gathered a strong interest in the scientific community and it is now one of the most attractive topics in the relativistic laser-plasma interaction research. Indeed, it could represent the future of particle acceleration and open new scenarios in multidisciplinary fields, in particular, medical applications. One of the biggest challenges consists of using, in a future perspective, high intensity laser-target interaction to generate high-energy ions for therapeutic purposes, eventually replacing the old paradigm of acceleration, characterized by huge and complex machines. In this framework, INFN-LNS (Italian Institute of Nuclear Physics, Catania (I)) in collaboration with ELI-Beamline Institute (Dolny Brezany, CZ) will realise, within 2017 the ELIMED (ELI-Beamlines MEDical and multidisciplinary applications) beamline. ELIMED will be the first Users' addressed transport beamline dedicated to the medical and multidisciplinary studies with laser-accelerated ion beams.

Slides WEXB01 [29.683 MB]

Export •

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