Bulletin of the American Physical Society
64th Annual Meeting of the APS Division of Plasma Physics
Volume 67, Number 15
Monday–Friday, October 17–21, 2022; Spokane, Washington
Session JO08: Laser-Plasma Ion AcceleratorsLive Streamed
|
Hide Abstracts |
Chair: Robbie Scott, STFC Rutherford Appleton Laboratory Room: 402 ABC |
Tuesday, October 18, 2022 2:00PM - 2:12PM |
JO08.00001: Tumor irradiation in mice with a laser-accelerated proton beam Florian-Emanuel Brack, Florian Kroll, Josefine Metzkes-Ng, Jörg Pawelke, Marvin Reimold, Ulrich Schramm, Tim Ziegler, Karl Zeil, Elke Beyreuther Recent oncological studies identified beneficial properties of radiation applied at ultra-high dose rates several orders of magnitude higher than the clinical standard of ~1 Gy/min. Sources capable of providing these ultra-high dose rates are under investigation. |
Tuesday, October 18, 2022 2:12PM - 2:24PM |
JO08.00002: Proton acceleration in an overdense hydrogen plasma by intense CO2 laser pulses with nonlinear focusing effects in the underdense preplasma Yu-hsin Chen, Antonio C Ting, Bahman Hafizi, Michael H Helle, Mikhail Polyanskiy, Igor Pogorelsky, Marcus Babzien, Nicholas P Dover, Oliver Ettlinger, George Hicks, Emma-Jane Ditter, Zulfikar Najmudin, Daniel F Gordon We report on proton acceleration from intense CO2 laser-irradiated hydrogen plasmas at near-critical densities, with the density gradient steepened by Nd:YAG ablation-driven hydrodynamic shocks. While the experimental results, including quasi-monoenergetic proton spectra and their scaling law with respect to the laser energy, generally agree with simulations, with some laser shots we observed much higher proton energies than expected. The increased proton energy may be linked to nonlinear propagation effects in the steepened plasma density ramp before the critical surface, including relativistic self-focusing and, for the case of temporally-structured laser pulses observed in the experiment, focusing of the trailing pulse through the plasma channel formed by the leading pulse 25 ps ahead. Formation of plasma ion channels by CO2 laser pulses was observed in a supplemental experiment. |
Tuesday, October 18, 2022 2:24PM - 2:36PM |
JO08.00003: A hybrid laser-RF compact proton accelerator to 250 MeV Jason Chou, Glen White, Valery Dolgashev, Sami Tantawi, Siegfried H Glenzer, Frederico Fiuza High-charge proton beams with 200+ MeV and small energy spread are important for applications such as therapy of deep-seated tumors. We use large 2D and 3D particle-in-cell (PIC) simulations to explore the development of a hybrid accelerator that combines the advantages of laser-driven (compact, high-charge, 10s MeV) proton beams with high-gradient RF acceleration (controllable beam energy and energy spread) in a meter-scale compact system, eliminating the need for large and expensive RFQ to perform bunching. We use an adaptive mesh technique to do fully-kinetic modeling of the system self-consistently, from the laser-solid interaction, transport, to the meter-scale acceleration in the RF. We find that space-charge field is minimized in transport due to the screening of accelerated electrons, but must be controlled in the RF stage for effective acceleration. We show that by tuning the distance of laser-plasma foil to the first RF cavity entrance, the space-charge field can be controlled such that it actually increases the beam capture and makes the accelerator more robust to the injection phase. We present end-to-end 3D simulations showcasing the possibility to develop a hybrid accelerator that captures a laser-driven proton beam at 40 MeV and produces a high-quality, high-charge 250 MeV beam in a few meters. |
Tuesday, October 18, 2022 2:36PM - 2:48PM |
JO08.00004: Simulation of optimized TNSA via temporal pulse shaping under realistic laser contrast conditions Marco Garten, Jakob Wetzel, Marvin Umlandt, Ilya Goethel, Thomas Miethlinger, Brian E Marré, Tim Ziegler, Thomas Pueschel, Stefan Bock, Karl Zeil, Michael Bussmann, Thomas E Cowan, Ulrich Schramm, Thomas Kluge Controlling the spatio-temporal coupling of laser energy into plasma electrons is crucial for achieving predictable beam parameters of ions accelerated from ultra-high intensity (UHI) laser-driven solid density plasmas. Especially for highest maximum energies, the most promising and readily available targets are foils of a few ten to hundred nanometers thickness. When working with targets of such small scales, meticulous control and precise metrology of the driving UHI laser pulses are paramount to avoiding premature plasma expansion that would lead to losses in absorption efficiency as well as lower accelerating fields. Recently, significant proton beam quality enhancement was reported from the Draco Petawatt facility at HZDR via spectral phase control of the driving laser pulse. In support of these experiments, we present a numerical simulation study with particle-in-cell codes taking into account realistic temporal intensity contrast features. In particular, we focus on the influence that manipulations of spectral phase terms applicable in laboratory experiments have on the acceleration of ions. We furthermore show how the state of the target and transient femtosecond plasma dynamics are encoded into time-integrated observables giving more insight into the previously obtained experimental results. |
Tuesday, October 18, 2022 2:48PM - 3:00PM |
JO08.00005: High repetition rate ion acceleration platform using ambient-temperature liquid jets Griffin Glenn, Hamad Ahmed, Sam Astbury, Mario Balcazar, Marco Borghesi, Nicholas Bourgeois, Christopher Crissman, Chandra Breanne Curry, Stephen J Dann, Daniel Deponte, Stephen Dilorio, Nicholas P Dover, Tom Dzelzainis, Oliver Ettlinger, Maxence Gauthier, Lorenzo Giuffrida, Siegfried H Glenzer, Ross Gray, James Green, George Hicks, Cormac Hyland, Valeriia Istokskaia, Martin King, Brendan Loughran, Daniele Margarone, Orla McCusker, Paul McKenna, Zulfikar Najmudin, Charlotte A Palmer, Claudia Parisuana, Peter Parsons, Christopher Spindloe, Matthew J. V Streeter, Dan R Symes, Alec G.R. Thomas, Franziska Treffert, Nuo Xu High-power laser-matter interactions are promising sources of high-energy, high-flux particle beams relevant to applications from fundamental science to cancer therapy. To fully realize these applications, it will be necessary to produce laser-driven particle beams at repetition rates of 1 Hz or above1,2. We have developed an ambient temperature, continuously-refreshing liquid jet target based on tungsten microfluidic nozzles. Here, we present an experimental platform based on this target that has demonstrated 5 Hz acceleration of laser-driven proton beams. We describe key features of the liquid jet target, as well as the suite of high repetition rate-compatible laser and particle diagnostics necessary to characterize the laser-target interaction and the laser-driven proton beam. Using these diagnostics, we confirm the performance of the liquid jet target as a source of laser-driven ion beams at high repetition rates. Finally, we illustrate applications of this platform to data-driven real-time optimization of laser-driven ion beam parameters. |
Tuesday, October 18, 2022 3:00PM - 3:12PM |
JO08.00006: Lateral confinement of fast electrons and its impact on laser ion acceleration Natsumi Iwata, Andreas J Kemp, Scott Wilks, Derek A Mariscal, Tammy Ma, Kunioki Mima, Dean Rusby, Alessio Morace, Yasuhiko Sentoku In intense laser-plasma interactions, maximizing the density of fast electrons in the laser spot area is key to achieving plasma heating and particle acceleration. We find that when the laser spot size is large compared with the target foil thickness, fast electrons circulating in the foil show a random walk in the lateral direction due to the scattering by fluctuating fields at the plasma surface inside the spot area. We model the lateral motion as a diffusion, and find the resulting diffusion velocity is much slower than the speed of the ballistic transport. Hence, fast electrons accumulate in the spot region, and over time their density becomes typically 10 times greater than the laser-accelerated fast electron density. The enhancement of fast electron density in the target pushes the ion acceleration to more efficient regime. The model is planned to be tested by a NIF Discovery Science experiment. |
Tuesday, October 18, 2022 3:12PM - 3:24PM |
JO08.00007: Laser ion implantation into Si and Diamond for Superconductivity and Quantum information applications Kaushalya Jhuria, Wei Liu, Zhihao Qin, Arun Persaud, Qing Ji, Tobias Ostermayr, Robert Jacob, Jeroen V Tilborg, Sahel Hakimi, Vincent Bagnoud, Johannes Hornung, Pascal Boller, Thomas Schenkel We report on the use of PW to TW laser-driven ion beams to implant various elements including boron and hydrocarbons into silicon and diamond for superconductivity and quantum telecommunication applications. We observe boron concentrations up to ~1.4x1022/cm3 when boron ions from a PW laser-driven ion pulse were implanted into silicon, corresponding to a fluence of ~1016 boron ions/cm2/shot. Time-resolved current measurements with 100 TW class laser shots show a very intense plasma expansion pulse of low energy ions (<1 keV) that trails the pulse of high energy ions from target normal sheath acceleration. Color centers, including qubit candidates such as G-centers in silicon, form directly under these conditions of intense (dual)-ion pulse irradiation and laser-ion doping. Very high boron concentrations can increase the transition temperature for superconductivity (from ~0.5 K in silicon and ~7 K in diamond) and we will report results from temperature dependent resistivity studies together with results from color center characterization. |
Tuesday, October 18, 2022 3:24PM - 3:36PM |
JO08.00008: Optimized laser ion acceleration at the relativistic critical density surface Thomas Kluge, Ilja Göthel, Constantin Bernert, Michael Bussmann, Marco Garten, Thomas Miethlinger, Martin Rehwald, Karl Zeil, Tim Ziegler, Thomas E Cowan, Ulrich Schramm In the effort of achieving high-energetic ion beams from the interaction of ultrashort laser pulses with a plasma, volumetric acceleration mechanisms beyond Target Normal Sheath Acceleration have gained attention. A relativisticly intense laser can turn a near critical density plasma slowly transparent, facilitating a synchronized acceleration of ions at the moving relativistic critical density front. While simulations promise extremely high ion energies in in this regime, the challenge resides in the realization of a synchronized movement of the ultra-relativistic laser pulse (a0≳30) driven reflective relativistic electron front and the fastest ions, which imposes a narrow parameter range on the laser and plasma parameters. We present an analytic model for the relevant processes, confirmed by a broad parameter simulation study in 1D- and 3D-geometry. By tayloring the pulse length, plasma density, and the density profile at the front side, we can optimize the proton acceleration performance and extend the regions in parameter space of efficient ion acceleration at the relativistic relativistic density surface. |
Tuesday, October 18, 2022 3:36PM - 3:48PM |
JO08.00009: Laser ion acceleration from tailored solid targets with micron-scale channels Kirill Lezhnin, Sergei V Bulanov Laser ion acceleration is a promising concept for generation of fast ions using a compact laser-solid interaction setup. In this study, we theoretically investigate the feasibility of ion acceleration from the interaction of petawatt-scale laser pulses with a structured target that embodies a micron-scale channel filled with relativistically transparent plasma. Using 2D and 3D Particle-In-Cell (PIC) simulations and theoretical estimates, we show that it is possible to generate GeV protons with high volumetric charge and quasi-monoenergetic feature in the energy spectrum. Optimal parameters of the target are obtained using 2D PIC simulations and interpreted on a basis of analytical two-stage ion acceleration model. 3D PIC simulations and realistic preplasma profile runs with 2D PIC show the feasibility of the presented laser ion acceleration scheme for the experimental implementation at the currently available petawatt laser facilities. |
Tuesday, October 18, 2022 3:48PM - 4:00PM Author not Attending |
JO08.00010: ion acceleration using ultra-short and intense laser pulse interaction with near critical plasmas in nano-structured targets GAURAV RAJ, Hartmut Ruhl We present a numerical investigation of the interaction of an ultra-short ultra-intense laser pulse with cylindrical nano-rods. We make use of full 3d particle-in-cell (PIC) simulations with the help of the simulation code MASIF. These studies are performed in the context of the paper by Ruhl and Korn [1], where they investigate the building blocks of a potential proton & boron-11 (pB11) fusion reactor. Our studies show that the interaction of the ultra-short ultra-intense laser pulse with cylindrical nano-structures leads to efficient acceleration of protons and boron ions via Coulomb explosions. We find that the energy loss of the laser pulse scales linearly with propagation depth. In addition, super-strong electromagnetic fields are generated in the target. |
Tuesday, October 18, 2022 4:00PM - 4:12PM |
JO08.00011: Investigation of proton-beam-driven fusion reactions generated by an ultra-short petawatt-scale laser pulse Marius Schollmeier, Vahe Shirvanyan, Christie Capper, Sven Steinke, Adam Higginson, Reed C Hollinger, John T Morrison, Ryan Nedbailo, Huanyu Song, Shoujun Wang, Jorge J Rocca, Georg Korn We present results from a pitcher-catcher experiment utilizing a proton beam generated with nano-structured targets to induce proton-boron fusion reactions in a secondary target. A 45-fs, 5x1021 W/cm² laser pulse with 400 nm wavelength and 7 J energy, or 800 nm and 14 J, was used to irradiate either thin foil targets or near-solid-density, nano-structured targets made of boron nitride (BN) nanotubes. In particular, for 800 nm wavelength irradiation a BN nanotube target created a proton beam with about 5x higher maximum energy and about 10x more protons than a foil target. This proton beam was used to irradiate a BN plate placed in close proximity to trigger 11B(p,α)2α fusion reactions. The primary spectrum was measured with a Thomson parabola ion spectrometer. Calculated (p,n) and (α,n) reactions in the catcher agree quantitatively with nuclear activation measurements; neutron time-of-flight data agree qualitatively, giving confidence that primary particle distributions can be obtained from such measurements. These results provide new insights for diagnosing the ion distributions inside an integrated proton-boron fusion device, such as for example the laser-driven, near-solid density, nano-structured micro-reactor concept [H. Ruhl, G. Korn, ArXiv 2202.03170, 2022]. |
Tuesday, October 18, 2022 4:12PM - 4:24PM |
JO08.00012: Double in-line plasma-mirror-based contrast enhanced laser-ion acceleration at the Centre for Advanced Laser Applications Valeriu Scutelnic, Martin Speicher, Katherine Kokmanian, Anja Schuster, Bruno González-Izquierdo, Vahe Shirvanyan, Jens Hartmann, Marius Schollmeier, Georg Korn, Felix Balling, Sonia Gerlach, Alexander Prasselsperger, Leonard Doyle, Florian Schweiger, Georg Schilling, Andreas Münzer, Jörg Schreiber, Sven Steinke Temporal laser contrast plays a vital role in laser-based fusion concepts, as for example the one recently proposed by Marvel Fusion (Ruhl and Korn, arXiv:2202.03170v5, 2022). We have demonstrated for the first time an in-line Double Plasma Mirror (DPM) setup at the Laser-driven ION (LION) beamline of the Centre for Advanced Laser Applications (CALA). This set-up yielded significant enhancement in laser contrast with as little as 20% losses. |
Tuesday, October 18, 2022 4:24PM - 4:36PM |
JO08.00013: A Meta-Analysis of Laser-Ion Acceleration Experiments Joseph R Smith, Nick Haught, Thomas Y Zhang, Pedro Gaxiola, Aditya Shah, Ricky Oropeza, Scott Feister, Alona Kryshchenko, Chris Orban Machine learning can help uncover new patterns in large datasets. In this study we apply machine learning to laser-ion acceleration data gathered from decades of previous experimental work, since the low-repetition-rates of intense laser systems have limited the size of datasets. This growing dataset consists of hundreds of distinct data points from tens of existing experimental campaigns on a variety of laser systems. From these experiments, we extract their parameters including intensity, pulse duration, wavelength, target thickness, and maximum proton energy. Our meta-analysis of laser-proton acceleration evaluates how existing theoretical/empirical models perform over this large parameter space. Then we apply machine learning methods including neural networks to find patterns in the data and help identify factors that can optimize laser-ion acceleration in future experiments. We plan to release this dataset in an open format that allows corrections and contributions of new data to encourage future collaboration among the community. |
Tuesday, October 18, 2022 4:36PM - 4:48PM |
JO08.00014: Multivariate scaling of maximum proton energy in intense laser driven ion acceleration Yuji TAKAGI, Natsumi Iwata, Emmanuel d’Humieres, Yasuhiko Sentoku The production of high-energy ions is a momentous goal of ultraintense laser lights. So far a number of experiments and numerical simulations have been conducted to obtain the scaling of the ion energy to find the optimal experimental condition. Due to the complexity of the relativistic laser-plasma interactions, it is not easy to evaluate the ion energy for different experimental configurations. We propose a statistical approach using the Bayesian inference to obtain a multivariate scaling to predict the maximum proton energy via the target normal sheath acceleration. We derive the scaling for the experimental parameters and also for the hot electron temperature and density observed in the corresponding particle-in-cell simulations[1]. We demonstrate the effectiveness of our approach in the prediction of the maximum proton energy and provide the experimental condition to achieve a proton energy over 100 MeV. |
Follow Us |
Engage
Become an APS Member |
My APS
Renew Membership |
Information for |
About APSThe American Physical Society (APS) is a non-profit membership organization working to advance the knowledge of physics. |
© 2024 American Physical Society
| All rights reserved | Terms of Use
| Contact Us
Headquarters
1 Physics Ellipse, College Park, MD 20740-3844
(301) 209-3200
Editorial Office
100 Motor Pkwy, Suite 110, Hauppauge, NY 11788
(631) 591-4000
Office of Public Affairs
529 14th St NW, Suite 1050, Washington, D.C. 20045-2001
(202) 662-8700