20th Advanced Accelerator Concepts Workshop

Hyatt Regency Long Island

Hyatt Regency Long Island

1717 Motor Parkway Hauppauge, New York 11788
Mark Palmer (Brookhaven National Laboratory) , Navid Vafaei-Najafabadi (Stony Brook University)

The AAC’22 workshop is the 20th in a series of by-invitation biennial fora for intensive discussions on long-term research in advanced accelerator physics and technology. This research supports the development of capabilities for the basic sciences, from photon science to high energy physics, as well as the development of compact accelerators for industrial, medical and security applications.

AAC'22 will be organized into eight working groups covering the following topical areas:

  1. Laser-Plasma Wakefield Acceleration 
  2. Computation for Accelerator Physics
  3. Laser and High-Gradient Structure-Based Acceleration
  4. Beam-Driven Acceleration
  5. Beam Sources, Monitoring, and Control
  6. Laser-Plasma Acceleration of Ions
  7. Radiation Generation and Advanced Concepts
  8. Advanced Laser and Beam Technology and Facilities

Conference Home:  https://www.aac2022.org/


Conference Coordinator
    • 18:00 19:30
      Welcome Reception 1h 30m Terrace Ballroom

      Terrace Ballroom

    • 08:50 10:20
      Plenary: Session 1 Ballroom Salon D-E

      Ballroom Salon D-E

      Convener: Eric Colby (DOE-ARDAP)
      • 08:50
        Acceleration beyond 10 GeV of a 340 pC electron bunch in a 10 cm nanoparticle-assisted wakefield accelerator 30m

        We present recent results from a proof-of-principle laser-plasma acceleration experiment that reveal a unique synergy between a laser-driven and particle-driven accelerator: a high-charge laser-wakefield accelerated electron bunch can drive a wakefield while simultaneously drawing energy from the laser pulse via direct laser acceleration. This process continues to accelerate electrons beyond the usual decelerating phase of the wakefield, thus reaching much higher energies. We find that the 10-centimeter-long nanoparticle-assisted wakefield accelerator can generate 340 pC, 10.4±0.6 GeV electron bunches with 3.4 GeV RMS convolved energy spread and 0.9 mrad RMS divergence. The nanoparticles control the amount of charge injected in the wakefield. This synergistic mechanism and the simplicity of the experimental setup represent a step closer to compact tabletop particle accelerators suitable for applications requiring high charge at high energies, such as radiation sources producing muon and positron beams.

        Speaker: Constantin Aniculaesei (The University of Texas at Austin)
      • 09:20
        Multi-GeV electron bunches from an all-optical laser wakefield accelerator 30m

        Conventional RF electron accelerators are limited by breakdown potentials to ~100 MeV/m. This poses significant economic and practical obstacles for the construction of new, high energy particle accelerators which can be used as advanced light sources, or as colliders to probe new fundamental physics regimes. Laser Wakefield accelerators (LWFAs), which can achieve acceleration gradients 1000 times greater, offer a promising alternative for the next generation of accelerators.

        LWFAs use the plasma waves (wakes) driven by an ultra-intense laser pulse to accelerate electron bunches to near luminal velocities. For maximal energy gain, the wave needs to be driven over tens of centimeters in a low-density (~$ 1\times10^{17} cm^{-3}$) plasma. This poses a natural problem since an ultra-high intensity laser pulse will diffract on a much shorter scale, reducing the intensity below that required to drive a wake in the plasma. We have recently demonstrated two methods, based on optical field ionization (OFI), to generate low-loss, meter-scale plasma waveguides (in hydrogen plasma) where high intensity guided modes can propagate hundreds of Rayleigh lengths [1,2].

        In this talk we will discuss the methods for optically generating plasma waveguides to enable meter scale LWFAs and the first successful implementation of the technique to accelerate electron bunches up to 5 GeV in a 20 cm all-optical LWFA [3]. We will present transverse plasma interferometry, guided mode images and optical spectra, electron beam profiles, and electron spectra collected during experimental campaigns on the ALEPH laser at Colorado State University, as well as particle in cell simulations to supplement the physical picture of the acceleration process.

        [1] B. Miao, et al. Optical guiding in meter-scale plasma waveguides, Phys. Rev. Lett. 125, 074801 (2020)
        [2] L. Feder et al., Self-waveguiding of relativistic laser pulses in neutral gas channels, Phys. Rev. Res. 2, 043173 (2020)
        [3] B. Miao et al., Multi-GeV electron bunches from an all-optical laser wakefield accelerator, Phys. Rev. X 12, 031038 (2022)

        Speakers: Bo Miao (University of Maryland) , Jaron Shrock (University of Maryland, College Park) , Ela Rockafellow (University of Maryland, College Park)
      • 09:50
        Experimental progress towards an energy-efficient, high-quality, high-repetition-rate plasma-wakefield accelerator 30m

        High-gradient plasma-wakefield acceleration represents an exciting route towards both boosting the energy and reducing the footprint of future particle colliders and free-electron lasers. At such facilities thousands or even millions of high-charge particle bunches with low energy spread and low emittance will need to be accelerated in an energy-efficient manner in order to outperform current machines in luminosity and brightness. In this contribution the latest results towards achieving this goal from the beam-driven plasma-acceleration experiment FLASHForward (DESY, Hamburg) will be presented. Highlights will include record values of the energy-transfer efficiency from drive beam to wake and from wake to the accelerating bunch; preservation of incoming bunch properties including charge, energy spread, and emittance; and first results in the direction of operating plasma accelerators at the repetition rates required for future high-energy-physics and photon-science applications.

        Speaker: Richard D'Arcy
    • 10:20 10:40
      Coffee Break 20m Grand Ballroom Pre Function

      Grand Ballroom Pre Function

    • 10:40 12:10
      Plenary: Session 2 Ballroom Salon D-E

      Ballroom Salon D-E

      Convener: Louise Willingale
      • 10:40
        Positron Acceleration in Plasmas 30m

        Stable acceleration of high-quality beams is a critical task for the realization of a plasma-based, linear collider. However, in plasma accelerators, the acceleration of collider-relevant positron beams is challenging even conceptually. Recently, many new positron acceleration schemes have been proposed to overcome this issue. In this talk, we review the latest advances on plasma-based positron acceleration concepts and their respective challenges. The path to collider-relevant beam parameters is discussed.

        Speaker: Severin Diederichs (DESY / LBNL)
      • 11:10
        High energy proton acceleration at DRACO-PW and radio-biological applications 30m

        Exploiting the strong electromagnetic fields that can be supported by a plasma, high-power laser driven compact plasma accelerators can generate short, high-intensity pulses of high energy ions with special beam properties. By that they may expand the portfolio of conventional machines in many application areas. The maturation of laser driven ion accelerators from physics experiments to turn-key sources for these applications will rely on breakthroughs in both, generated beam parameters (kinetic energy, flux), as well as increased reproducibility, robustness and scalability to high repetition rate.

        Recent developments at the high-power laser facility DRACO-PW enabled the production of polychromatic proton beams with unprecedented stability [1]. This allowed the first in vivo radiobiological study to be conducted using a laser-driven proton source [2]. Yet, the ability to achieve energies beyond the 100 MeV frontier is matter of ongoing research, mainly addressed by exploring advanced acceleration schemes like the relativistically induced transparency (RIT) regime.

        In this talk we report on experimental proton acceleration studies at the onset of relativistic transparency using pre-expanded plastic foils. Combined hydrodynamic and 3D particle-in-cell (PIC) simulations helped to identify the most promising target parameter range matched to the prevailing laser contrast conditions carefully mapped out in great detail beforehand. A complex suite of particle and optical diagnostics allowed characterization of spatial and spectral proton beam parameters and the stability of the regime of best acceleration performance, yielding cut-off energies larger than 100 MeV in the best shots.

        [1] Ziegler, T. et al. Proton beam quality enhancement by spectral phase control of a PW-class laser system. Sci Rep 11, 7338 (2021)
        [2] Kroll, F. et al. Tumour irradiation in mice with a laser-accelerated proton beam. Nat. Phys. 18, 316–322 (2022)

        Speaker: Karl Zeil (Helmholtz-Zentrum Dresden-Rossendorf)
      • 11:40
        First SASE and Seeded FEL Lasing based on a beam driven wakefield accelerator 30m

        The breakthrough provided by plasma-based accelerators enabled unprecedented accelerating fields by boosting electron beams to GeV energies within few cm. This enables the realization of table-top accelerators able to drive a Free-Electron Laser (FEL), a formidable tool to investigate matter at sub-atomic level by generating X-UV coherent light pulses with fs and sub-fs durations.
        So far, short wavelength FELs had to rely on the use of conventional large-size radio-frequency (RF) accelerators due to the limited accelerating fields provided by such a technology. Here we report the experimental evidence of a FEL driven by a compact plasma-based accelerator. The accelerated beams are characterized in the six-dimensional phase-space and have a quality comparable with state-of-the-art accelerators. This allowed the observation of amplified SASE radiation in the infrared range with typical pulse energy exponential growth, reaching tens of nJ over six consecutive undulators.
        On the basis of these first amplification results starting from spontaneous emission (SASE), we upgraded the setup by seeding the amplifier with an external laser. Compared to SASE, the seeded FEL pulses are characterized by a higher pulse energy, two orders of magnitude larger (up to about 1 uJ) and an enhanced reproducibility (up to about 90%) resulting in a higher shot-to-shot stability.

        Speaker: Angelo Biagioni (INFN)
    • 12:10 13:30
      Lunch 1h 20m
    • 15:00 15:30
      Coffee Break 30m Grand Ballroom Pre Function

      Grand Ballroom Pre Function

    • 08:30 10:00
      Plenary: Session 3 Ballroom Salon D-E

      Ballroom Salon D-E

      Convener: Vladimir Shiltsev (Fermilab)
      • 08:30
        FACET-II: Status of the first experiments and the road ahead 30m

        The FACET-II facility at SLAC National Accelerator Laboratory conducts a broad science program based on the interaction of low-emittance high-current 10 GeV electron beams with lasers, plasmas and solids. FACET-II operates as a National User Facility while engaging a broad User community to develop and execute experimental proposals that advance the development of plasma wakefield accelerators. The FACET-II facility has completed construction, initial commissioning and began first experiments in the summer of 2022. The special features of FACET-II will be shown and the status of the first experiments invited for beam time will be presented.

        Speaker: Dr Mark Hogan (SLAC National Accelerator Laboratory)
      • 09:00
        Hosing of a long relativistic particle bunch induced by an electron bunch 30m

        Hosing of particle bunches [1] (or laser pulses) driving or experiencing wakefields in plasma may impose limits on the quality and efficiency [2] of the acceleration process. Understanding and measuring hosing is therefore important and interesting. We present an experimental study of hosing of a long proton bunch in plasma. We induce hosing with the relative misalignment between the trajectory of a short electron bunch driving initial wakefields, and that of the proton bunch following it. The effect of the wakefields on the proton bunch is thus non-axi-symmetric. This asymmetry leads to transverse oscillation of the proton bunch centroid position in the plane of misalignment. Self-modulation (SM) takes place in the perpendicular plane. SM [3] and hosing are induced and are thus reproducible from event to event. They grow from similar amplitudes of the transverse wakefields, and with similar predicted growth rates[4]. They are thus coupled. While SM occurs as an instability without the electron bunch, hosing does not (except at much lower plasma densities). We observe hosing and SM on time-resolved images of the proton bunch density distribution, obtained at a screen 3.5m downstream from the exit of the 10m-long plasma. The amplitude of hosing increases along the bunch. It depends on the charge of the proton bunch, as well as on the extent of misalignment. The direction of hosing reverses with the direction of misalignment. The frequencies of hosing (oscillation of centroid position) and of SM (modulation of the bunch density, no detectable oscillation of centroid position) are close to plasma electron frequency and thus scale with plasma density. We will introduce the AWAKE experiment, describe the experimental setup and give an overview of the latest experimental results.
        [1] D. Whittum et al., Phys. Rev. Lett. 67, 991 (1991)
        [2] V. Lebedev et al., 20, Phys. Rev. AB 20, 121301 (2017)
        [3] L. Verra et al. (AWAKE Collaboration), Phys. Rev. Lett. 129 024802 (2022)
        [4] C. B. Schroeder et al., Phys. Rev. E 86, 026402 (2013)

        Speaker: Tatiana Nechaeva (Max-Planck-Institut fur Physik (DE))
      • 09:30
        European Roadmap Reports for Advanced Accelerators 30m

        In recent years Europe had an intense discussion on roadmaps for accelerator R&D and research infrastructures. Several roadmaps were published and prominently include advanced accelerators. Of particular visibility are the 2021 Roadmap Update of the government-led European Strategy Forum for Research Infrastructures (ESFRI) and the 2022 publication of the European Roadmap on Accelerator R&D for Particle Physics. For the first time an advanced accelerator facility project, namely EuPRAXIA, was selected for the ESFRI roadmap. Also for the first time, advanced accelerators have been recognised as one of several pillars of the European particle physics accelerator R&D roadmap, relating to various national projects and the CERN AWAKE collaboration. The conclusions and advanced accelerator R&D directions of the recently published roadmaps are presented. Future R&D work and approved European facilities in advanced accelerator research are discussed.

        Speaker: Ralph Assmann (DESY & INFN)
    • 10:00 10:30
      Coffee Break 30m Grand Ballroom Pre Function

      Grand Ballroom Pre Function

    • 10:30 12:00
      Plenary: Session 4 Ballroom Salon D-E

      Ballroom Salon D-E

      Convener: John Power
      • 10:30
        Breakdown insensitive acceleration regime in structure wakefield acceleration 30m

        Structure wakefield acceleration is an advanced accelerator concept which employs short drive electron bunches as compact power sources to accelerate witness bunches. It is promising to raise the accelerating gradient, which is limited to about 100 MV/m in conventional RF accelerators due to RF breakdowns, by confining an intense wakefield in short RF pulses. Based on the extensive research in the high gradient acceleration community, using short RF pulses could mitigate the risk of RF breakdown and increase the operating gradient as a result. In a few recent experiments at the Argonne Wakefield Accelerator (AWA), including an X-band single-cell metallic structure, and an X-band metamaterial accelerating structure, we discovered evidence for a new operating regime, named the breakdown insensitive accelerating regime (BIAR), where the RF pulse for acceleration (or the accelerating field in the structure) is not disrupted in a breakdown event. The pulse length is short, on the order of a few nanoseconds. The BIAR regime could lead to high-gradient acceleration as well as breakthrough in understanding RF breakdown physics.

        Speaker: Xueying Lu (NIU / ANL)
      • 11:00
        From Compact Plasma Particle Sources to Advanced Accelerators with Modeling at Exascale 30m

        Research of plasma-based accelerators has achieved significant milestones over the last decade. Highlights include achieving nearly 8 GeV electrons in a single-stage source, demonstrating plasma-based FELs, reaching stable proton acceleration of ultra-short, nC-class pulses that enable studies into ultrahigh dose rate radiotherapy. As the exploratory aspect of the field benefits significantly from the elucidation of fundamental processes through simulations, transitioning from intriguing sources to scalable accelerators requires universally integrated, quantitatively predictive capabilities for design and operations.
        In this presentation, we discuss that complex, reliable advanced accelerators require a coordinated, extensible, and comprehensive approach in modeling, from source to the end of the beam’s lifetime. We will discuss approaches and highlights of ongoing Exascale Computing efforts in the community, both in the US and internationally. This includes laser-plasma modeling on an exaflop supercomputer using the US DOE Exascale Computing Project WarpX [1-4] as well as progress of PIConGPU in the OLCF Center for Accelerated Application Readiness (CAAR) project for the same machine, and further projects.
        Leveraging developments for Exascale, the DOE SCIDAC-5 Consortium for Advanced Modeling of Particle Accelerators (CAMPA) will advance numerical algorithms and accelerate community modeling codes in a cohesive manner: from beam source, over energy boost, transport, injection, storage, to application or interaction. Such start-to-end modeling will enable the exploration of hybrid accelerators, with conventional and advanced elements, as the next step for advanced accelerator modeling. Following open community standards [5], one can initiate an open ecosystem of codes [6,7] that can be readily combined with each other and machine learning frameworks. These will cover ultrafast to ultraprecise modeling for future hybrid accelerator design, even enabling virtual test stands and twins of accelerators that can be used in operations.

        Speaker: Axel Huebl (Lawrence Berkeley National Laboratory)
      • 11:30
        Advanced Ion Acceleration Mechanisms 30m

        Abstract: One of the main applications of high power laser facilities is particle acceleration. It is due to the fact that ultrashort laser pulses in plasma are able to generate electromagnetic fields exceeding those typical for the conventional accelerators by many orders of magnitude. Laser ion acceleration is of particular interest due to unique beam properties and its potential application in basic and material science, medicine, industry, etc. There are several possible regimes where different ion acceleration mechanisms may be accessed, depending on target and laser parameters. The most well known of them is Target Normal Sheath Acceleration. However, the quest for more efficient acceleration of ion beams having different spectral features gave rise to several other advanced ion acceleration mechanisms, such as Magnetic Vortex Acceleration and Radiation Pressure Acceleration. Here the basic theoretical concepts for several advanced ion acceleration mechanisms will be presented as well as recent analytical and computer simulation results.

        Speaker: Stepan Bulanov (LBNL)
    • 12:00 13:20
      Lunch 1h 20m Terrace Ballroom

      Terrace Ballroom

    • 15:00 15:30
      Coffee Break/Exhibits 30m Grand Ballroom Pre Function

      Grand Ballroom Pre Function

    • 08:30 10:00
      Plenary: Session 5 Ballroom Salon D-E

      Ballroom Salon D-E

      Convener: Pietro Musumeci
      • 08:30
        Summary of the Snowmass Accelerator Frontier - AAC Role and Vision 20m

        Snowmass is the name for a decadal planning exercise by the US high particle physics community. It provides an opportunity for the entire particle physics community to come together to identify and document a scientific vision for the future of particle physics in the U.S. and its international partners. The Snowmass exercise takes roughly a year (2 years including the impact of Covid) and defined the most important questions for the field of particle physics and worked to identify promising opportunities to address them. The exercise is organized into 10 Frontiers, one of which is the Accelerator Frontier. The Accelerator Frontier was focused on accelerator science and technology that may be able to address the important questions in particle physics. This talk will describe the Snowmass exercise and will summarize some of the conclusions from the Accelerator Frontier.

        Speaker: Tor Raubenheimer (SLAC National Accelerator Laboratory)
      • 08:50
        Snowmass Process Advanced Accelerator Concepts (AF6) Perspective 20m

        Snowmass Accelerator Frontier topical group # 6, Advanced Accelerator Concepts (https://doi.org/10.48550/arXiv.2208.13279), covered new R\&D concepts for particle acceleration, generation, and focusing at ultra high acceleration gradients (GeV/m and beyond). Leveraging these to efficiently harness the interaction of charged particles with extremely high electromagnetic fields at very high frequencies has the potential to enable future e+e- and $\gamma - \gamma$ colliders to and beyond 15 TeV energies. In addition to proven high gradient and ultra-bright beam generation, these systems have the potential to increase luminosity per unit beam power via short beams, for practical energy recovery to extend the reach of high energy physics, and for fast cooling. They hence have potential to reduce the dimensions, CO$_2$ footprint, and costs of future colliders, with added potential to reduce power consumption. Techniques range from laser and beam driven plasma and advanced structure accelerators to advanced phase space manipulations and generation of beams with extreme parameters. The last decade has seen tremendous progress including the demonstration of multi-GeV acceleration in a single stage, positron acceleration, efficient loading of the structure, the first staging of plasma accelerators, demonstration of beam shaping to improve efficiency in plasmas and structures, high gradient structures and greatly improved beam quality which recently culminated in the spectacular first demonstrations of laser-driven and beam-driven plasma based FELs. At the same time, solutions for potential collider issues have been identified. Conceptual parameter sets for colliders have been developed for e+e- and $\gamma \gamma$ colliders at a range of energies, which present potentially competitive options with prospects for future cost reduction. In addition to a strengthened ongoing R$\&$D program, continuing to advance collider concepts in interaction with the collider and high energy physics communities, starting with an integrated set of parameters, is important as is development of technologies through nearer-term applications.

        Speaker: Cameron Geddes (Lawrence Berkeley National Laboratory)
      • 09:10
        The GARD Program - A Retrospective View 20m

        Understanding the history and evolution of a program can often provide valuable information and a foundation on which to plan a strategy for future successes. It is with this view in mind that a retrospective discussion of the General Accelerator Research and Development (GARD) program at the Office of High Energy Physics, U.S. Department of Energy, of which the Advanced Accelerator Concepts Thrust is a part, will be presented. GARD's origin can be traced to the HEP Advanced Technology R&D subprogram. Its portfolio and research scope have evolved over the years through several reorganizations within the Office of High Energy Physics. A historical perspective of the program, including its research strategy and management process together with the R&D activities it supports will be presented.

        Speaker: LK Len (DOE (retired))
      • 09:30
        Panel Discussion 30m

        Discussion of the AAC Vision and Future

        Panel: Tor Raubenheimer, Vladimir Shiltsev, Cameron Geddes, Pietro Musumeci, Mark Hogan, and LK Len

    • 10:00 10:30
      Coffee Break/Exhibits 30m Grand Ballroom Pre-Function

      Grand Ballroom Pre-Function

    • 10:30 12:00
      Plenary: Session 6 Ballroom Salon D-E

      Ballroom Salon D-E

      Convener: Dr Eric Esarey (Lawrence Berkeley National Laboratory)
      • 10:30
        Prospects of Ultralow MTE photocathodes in Electron Guns 30m

        Brightness of electron beams is directly proportional to the accelerating electric field at the cathode and inversely proportional to the mean transverse energy (MTE) of electrons emitted from photocathodes. Thus, maximizing the brightness of electron beams requires the use of lowest possible MTE photocathodes in the highest possible electric fields. While the maximum electric field is limited by the electric breakdown and design of the electron gun, the MTE is a property of the cathode material, its surface and the laser used for excitation. MTEs of up to two orders of magnitude lower than those typically used in photoinjectors today have been demonstrated by using atomically ordered surfaces at cryogenic temperatures with photon energy very close to the emission threshold. In this talk, I will discuss the various hurdles in using such low MTE photocathodes in high field electron guns and elaborate on the recent progress towards achieving this.

        Speaker: Siddharth Karkare
      • 11:00
        Machine-learning control of coherent combining of fiber lasers for plasma accelerators 30m

        One of the most promising technical paths to high-average-power, high-peak-power, ultrafast lasers is coherent combination of fiber lasers, which could produce Joule/kHz laser pulses to drive next-generation laser-plasma accelerators (LPA), e.g. kBELLA (kilohertz Berkeley Lab Laser Accelerator). Advanced controls are essential for many-beam, many-pulse coherent combination, and to optimize the overall laser system by sensing, diagnosing, and controlling at high speed (as compared with perturbations). Advanced machine learning (ML) has proved to be advantageous over more commonly used algorithms for complex systems where errors are irretrievable from measured data (e.g. phase error from amplitude data), or the system has too many unknown, time-varying parameters and is highly nonlinear, preventing deterministic error prediction. We have created innovative solutions to address some of the key challenges in ML control, to enable ML to learn on an unstable system with noise and drift. We have, for the first time, demonstrated stabilizing laser power with ten times faster convergence speed than random dither-and-search algorithms and experimentally demonstrated 0.4% stability with high combining efficiency when coherently combining 8 beams. Key features of our novel ML-based active feedback controls include scaling to many outputs while retaining high speed, and ability to actively re-learn while in operation. We are also implementing ML on Field-Programmable Gate Arrays (FPGA) to reduce the control latency to microseconds, to enable fast control over >10 kHz repetition rate and allow precision controls to reach optimal error reduction and stability. This approach will provide a robust technical path to active control of coherently-combined multi-kHz, high-power ultrafast lasers, achieving the power stability and combining efficiency needed for laser-based accelerators.

        Speaker: Dan Wang (LBNL)
      • 11:30
        RadiaBeam and lessons learned building an accelerator company 30m

        The advanced accelerator community is well familiar with high-risk initiatives, which has led to multi-decade development programs before concepts are realized. What is less obvious is that building an accelerator company requires continuous development on a similar time scale, and is not entirely dissimilar in nature. RadiaBeam was spun off in 2004 from UCLA's advanced accelerator laboratory, and its foundation was in many ways an experiment, in and of itself. Just like in many advanced accelerator projects, the founders overestimated the progress that could be made in a few years; and yet completely underestimated the success that can be achieved in over a decade. By 2022 RadiaBeam became a vital part of the world accelerator community, contributing to the advancement of accelerator technology and applications in research, industry, medicine, and security.
        Unique among small accelerator manufacturers, RadiaBeam performs its own design, engineering, manufacturing, tuning, and testing, including “hot” testing, in-house. Yet, despite a considerable degree of self-sufficiency, RadiaBeam remains an organic part of the accelerator community and is ever more dependent on the ideas, skills, and sense of purpose propelling the entire field. Most of RadiaBeam's capabilities have been developed in collaboration with US national laboratories and universities under the realm of the DOE Small Business Innovation Research (SBIR) program.
        Many RadiaBeam products are currently in service in laboratories, hospitals, and universities around the world. On the other hand, many of our R&D projects have either failed, or never been completed, or never obtained any traction with the market or funding agencies, and many important capabilities the company had aspired to achieve have yet to be realized. This necessary hard work of trial and error inevitably expresses itself in the ponderomotive nature of the company’s growth and defines the long-term vision of RadiaBeam’s mission as a business, and as a partner to the larger US accelerator community.
        In this talk, we will discuss the company’s development history, the role of the U.S. SBIR/STTR programs, the successes and failures of developing products for National Laboratories and industrial customers, and the fine balance between R&D and industrial production activities.

        Speaker: Dr Sergey Kutsaev (RadiaBeam Technologies, LLC)
    • 12:00 13:20
      Lunch 1h 20m Terrace Ballroom

      Terrace Ballroom

    • 10:00 10:30
      Coffee Break/Exhibits 30m Grand Ballroom Pre-Function

      Grand Ballroom Pre-Function

    • 12:00 13:20
      Lunch 1h 20m Terrace Ballroom

      Terrace Ballroom

    • 15:00 18:00
      Afternoon at Leisure 3h
    • 08:30 10:00
      Plenary: Session 7 Ballroom Salon D-E

      Ballroom Salon D-E

      Convener: Evgenya Simakov (LANL)
      • 08:30
        Cool Copper Collider Design and Plans 30m

        C3 – the Cool Copper Collider – is a concept for a e+e− Higgs factory at 250 GeV center of mass, with a potential upgrade to 550 GeV in the same footprint. C3 leverages novel advancements in high-gradient cryogenic copper accelerator structures which operate with high rf to beam efficiency. The C3 main linac requires significant R&D effort for the rf and cryogenic systems, beam delivery, and beam alignment. The C3 demonstration plan is aimed at mitigating risks associated with technical, schedule, and cost with the goal of commissioning a full high gradient cryomodule with beam loading. This talk will cover recent rf accelerator R&D efforts in terms of distributed coupling structures and cryogenic structure design, as well as the status of high gradient tests, cryomodule design and beam dynamics.

      • 09:00
        ACE3P – Multi-Physics Modeling, Enabling Technologies, and Code Integration 30m

        ACE3P is a comprehensive set of parallel finite-element codes for multi-physics modeling of particle accelerators. Running on massively parallel computer platforms for high fidelity and high accuracy simulation, ACE3P enables rapid virtual prototyping of accelerator rf component design, optimization, and analysis. Recent advances of ACE3P have been achieved through the implementation of advanced numerical algorithms, enhancement of multi-physics modeling capabilities, integration with beams dynamics (IMPACT) and particle-matter interaction (Geant4) codes toward start-to-end simulation, and improvement of code performance on state-of-the-art high-performance computing (HPC) platforms for large-scale computation. ACE3P has been applied to the design and optimization of many DOE accelerator projects nationwide. In this paper, we will focus on ACE3P applications to high brightness injectors and high gradient accelerators. Using ACE3P enhanced multi-physics modeling capabilities, rf performance has been fully evaluated covering cavity shape design, multipacting, thermal and mechanical analysis for the NC and SRF guns in LCLS-II and LCLS-II-HE, respectively. A3PI, an integrated ACE3P-IMPACT workflow, provides realistic studies of beam performance for the LCLS-II Low Emittance Injector (LEI) accelerator system from start to end including gun cavity imperfections. ACE3P has been used to design and optimize the novel high gradient distributed-coupling accelerator cavity for the proposed Higgs factory C3 using Cool Copper C-band technology. The implementation of an integrated ACE3P-Geant4 workflow is underway with the ultimate objective of determining dark current radiation effects in high gradient accelerator systems. Furthermore, SLAC has collaborated with Kitware and Simmetrix through SBIR to make ACE3P more accessible to a broader accelerator community by the development of enabling technologies in GUI, simulation workflow for HPC systems, and advanced meshing techniques for automatic shape optimization. All the simulations presented in this paper have been performed on the computing resources at the National Energy Research Scientific Computing Center (NERSC).

        Speaker: Liling Xiao (SLAC)
      • 09:30
        Plasma-based Attosecond X-ray Pulses 30m

        Attosecond science has emerged as a major research direction in X-ray free-electron laser science. X-ray free-electron lasers can routinely generate attosecond pulses with a peak power in the tens to hundreds of GW and are employed for time-resolved experiments with sub-fs resolution.

        Plasma-based injectors have the potential revolutionize ultrafast science thanks to their ability to generate high current bunches with a brightness that is orders of magnitude larger than conventional photoinjectors.

        In my talk I will discuss our ongoing R&D efforts towards plasma-based attosecond X-ray pulses. By employing the strong accelerating field of plasma-based accelerators, we propose to chirp and compress high-brightness electron bunches to nm-scale lengths. The resulting charge distribution can emit coherently in the soft X-ray range, resulting in few-cycle pulses with TW peak powers.

        This experiment can combine the bandwidth of state-of-the-art harmonic sources with the peak power of X-ray free-electron lasers, and open new directions in attosecond science.

        Speaker: Dr Agostino Marinelli (SLAC National Accelerator Laboratory)
    • 10:00 10:30
      Coffee Break 30m
    • 10:30 12:00
      Plenary: Student Poster Prize Winners Ballroom Salon D-E

      Ballroom Salon D-E

      Convener: Michael Downer (The University of Texas at Austin)
    • 12:00 13:00
      Lunch 1h Terrace Ballroom

      Terrace Ballroom

    • 14:40 15:00
      Coffee Break 20m Grand Ballroom Pre-Function

      Grand Ballroom Pre-Function