The Energy Sciences Network (ESnet) is the high-performance network user facility for the US Department of Energy (DOE) Office of Science (SC) and delivers highly reliable data transport capabilities optimized for the requirements of data-intensive science. In essence, ESnet is the circulatory system that enables the DOE science mission by connecting all its laboratories and facilities in the US and abroad. ESnet is funded and stewarded by the Advanced Scientific Computing Research (ASCR) program and managed and operated by the Scientific Networking Division at Lawrence Berkeley National Laboratory (LBNL). ESnet is widely regarded as a global leader in the research and education (R&E) networking community. In April 2022, ESnet and the Office of High Energy Physics (HEP) of the DOE SC organized an ESnet requirements review of HEP-supported activities. Preparation for the review included identification of key stakeholders: program and facility management, research groups, and technology providers. Each stakeholder group was asked to prepare formal case study documents about the group’s relationship to the HEP program to build a complete understanding of the current, near-term, and long-term status, expectations, and processes that will support the science going forward. A series of pre-planning meetings better prepared case study authors for this task, along with guidance on how the review would proceed in a virtual fashion.

Over several months, representatives from the U.S. Department of Energy (DOE) Office of Science and National Institutes of Health (NIH) had a number of meetings that lead to the conclusion that innovations in the Nation's health care could be realized by more directed interactions between NIH and DOE. It became clear that the expertise amassed and instrumentation advances developed at the DOE physical science laboratories to enable cutting-edge research in particle physics could also feed innovation in medical healthcare. To meet their scientific mission, the DOE laboratories created advances in such technologies as particle beam generation, radioisotope production, high-energy particle detection and imaging, superconducting particle accelerators, superconducting magnets, cryogenics, high-speed electronics, artificial intelligence, and big data. To move forward, NIH and DOE initiated the process of convening a joint workshop which occurred on July 12th and 13th, 2021. This Special Report presents a summary of the findings of the collaborative workshop and introduces the goals of the next one.

Author(s): Zurawski, Jason; Brown, Benjamin; Carder, Dale; Colby, Eric; Dart, Eli; Miller, Ken; Patwa, Abid; Robinson, Kate; Rotman, Lauren; Wiedlea, Andrew | Abstract: The Energy Sciences Network (ESnet) is the high-performance network user facility for the US Department of Energy​ (DOE) ​Office​ of​ Science​ (SC)​ and​ delivers​ highly​ reliable​ data​transport ​capabilities​ optimized​ for ​the​ requirements of data-intensive science. In essence, ESnet is the circulatory system that enables the DOE science mission by connecting all of its laboratories and facilities in the United States and abroad. ESnet is funded and stewarded​ by​ the​ Advanced​ Scientific ​Computing​ Research​ (ASCR)​ program​ and​ managed​ and​operated​ by​ the​ Scientific ​Networking​ Division​ at ​Lawrence​ Berkeley ​National​ Laboratory​ (LBNL). ​ESnet ​is ​widely​ regarded​ as​ a global leader in the research and education networking community. Throughout ​2020,​ESnet​ and​ the ​Office ​of ​High ​Energy​ Physics​ (HEP)​ of ​the ​DOE​ SC​ organized​ an​ ESnet​ requirements ​review​ of ​HEP-supported​ activities.​ Preparation ​for ​this​ event​included​ identification ​of​ key​ stakeholders: program and facility management, research groups, technology providers, and a number of external observers. These individuals were asked to prepare formal case study documents about their relationship to the HEP program to build a complete understanding of the current, near-term, and long-term status, expectations, and processes that will support the science going forward. A series of pre-planning meetings better prepared case study authors for this task, along with guidance on how the review would proceed in a virtual fashion. ESnet and ASCR use requirements reviews to discuss and analyze current and planned science use cases and anticipated data output of a particular program, user facility, or project to inform ESnet’s strategic planning, including network operations, capacity upgrades, and other service investments. A requirements review comprehensively surveys major science stakeholders’ plans and processes in order to investigate data management requirements over the next 5–10 years.

Throughout 2020, ESnet and the Office of High Energy Physics (HEP) of the DOE SC organized an ESnet requirements review of HEP-supported activities. Preparation for this event included identification of key stakeholders: program and facility management, research groups, technology providers, and a number of external observers. These individuals were asked to prepare formal case study documents about their relationship to the HEP program to build a complete understanding of the current, near-term, and long-term status, expectations, and processes that will support the science going forward. A series of pre-planning meetings better prepared case study authors for this task, along with guidance on how the review would proceed in a virtual fashion.

Most particle accelerators today are expensive devices found only in the largest laboratories, industries, and hospitals. Using techniques developed nearly a century ago, the limiting performance of these accelerators is often traceable to material limitations, power source capabilities, and the cost tolerance of the application. Advanced accelerator concepts a aim to increase the gradient of accelerators by orders of magnitude, using new power sources (e.g. lasers and relativistic beams) and new materials (e.g. dielectrics, metamaterials, and plasmas). Worldwide, research in this area has grown steadily in intensity since the 1980s, resulting in demonstrations of accelerating gradients that are orders of magnitude higher than for conventional techniques. While research is still in the early stages, these techniques have begun to demonstrate the potential to radically change accelerators, making them much more compact, and extending the reach of these tools of science into the angstrom and attosecond realms. Maturation of these techniques into robust, engineered devices will require sustained interdisciplinary, collaborative R&D and coherent use of test infrastructure worldwide. The outcome can potentially transform how accelerators are used.

PURPOSE:To measure radiation dose in a water-equivalent medium from very high-energy electron (VHEE) beams and make comparisons to Monte Carlo (MC) simulation results.METHODS:Dose in a polystyrene phantom delivered by an experimental VHEE beam line was measured with Gafchromic films for three 50 MeV and two 70 MeV Gaussian beams of 4.0-6.9 mm FWHM and compared to corresponding MC-simulated dose distributions. MC dose in the polystyrene phantom was calculated with the EGSnrc/BEAMnrc and DOSXYZnrc codes based on the experimental setup. Additionally, the effect of 2% beam energy measurement uncertainty and possible non-zero beam angular spread on MC dose distributions was evaluated.RESULTS:MC simulated percentage depth dose (PDD) curves agreed with measurements within 4% for all beam sizes at both 50 and 70 MeV VHEE beams. Central axis PDD at 8 cm depth ranged from 14% to 19% for the 5.4-6.9 mm 50 MeV beams and it ranged from 14% to 18% for the 4.0-4.5 mm 70 MeV beams. MC simulated relative beam profiles of regularly shaped Gaussian beams evaluated at depths of 0.64 to 7.46 cm agreed with measurements to within 5%. A 2% beam energy uncertainty and 0.286° beam angular spread corresponded to a maximum 3.0% and 3.8% difference in depth dose curves of the 50 and 70 MeV electron beams, respectively. Absolute dose differences between MC simulations and film measurements of regularly shaped Gaussian beams were between 10% and 42%.CONCLUSIONS:The authors demonstrate that relative dose distributions for VHEE beams of 50-70 MeV can be measured with Gafchromic films and modeled with Monte Carlo simulations to an accuracy of 5%. The reported absolute dose differences likely caused by imperfect beam steering and subsequent charge loss revealed the importance of accurate VHEE beam control and diagnostics.

We report the fabrication and first demonstration of an electron beam position monitor for a dielectric microaccelerator. This device is fabricated on a fused silica substrate using standard optical lithography techniques and uses the radiated optical wavelength to measure the electron beam position with a resolution of 10 μm, or 7% of the electron beam spot size. This device also measures the electron beam spot size in one dimension.

The first ICFA Mini-Workshop on dielectric laser accelerators (DLA) was held on September 15–16, 2011 at SLAC National Accelerator Laboratory. We present the results of the workshop, and discuss the main conclusions of the Accelerator Applications, Photonics, and Laser Technologies working groups. Over 50 participants from four countries participated, discussing the state of the art in photonic structures, laser science, and nanofabrication as it pertains to laser-driven particle acceleration in dielectric structures. Applications of this new and promising acceleration concept to discovery science and industrial, medical, and basic energy sciences were explored. The DLA community is presently focused on making demonstrations of high gradient acceleration and a compatible atto-second injector source, two critical steps towards realizing the potential of this technology.

The first ICFA Mini-workshop on Dielectric Laser Accelerators was held on September 15-16, 2011 at SLAC National Accelerator Laboratory. We present the results of the Workshop, and discuss the main conclusions of the Accelerator Applications, Photonics, and Laser Technologies working groups. Over 50 participants from 4 countries participated, discussing the state of the art in photonic structures, laser science, and nanofabrication as it pertains to laser-driven particle acceleration in dielectric structures. Applications of this new and promising acceleration concept to discovery science and industrial, medical, and basic energy sciences were explored. The DLA community is presently focused on making demonstrations of high gradient acceleration and a compatible attosecond injector source—two critical steps towards realizing the potential of this technology.

eleration of relativistic electrons in a dielectric laser accelerator at high electric field gradients is reported, setting the stage for the development of future multi-staged accelerators of this type.

Get PDF Email Share Share with Facebook Tweet This Post on reddit Share with LinkedIn Add to CiteULike Add to Mendeley Add to BibSonomy Get Citation Copy Citation Text E. A. Peralta, K. Soong, R. J. England, E. R. Colby, Z. Wu, B. Montazeri, C. McGuinness, J. McNeur, K. J. Leedle, D. Walz, E. Sozer, B. Cowan, B. Schwartz, G. Travish, and R. L. Byer, "ACCELERATION OF ELECTRONS IN A LASER-DRIVEN DIELECTRIC MICRO-STRUCTURE," in Nonlinear Optics, B. Boulanger, S. Cundiff, M. Kauranen, and W. Knox, eds., OSA Technical Digest (online) (Optica Publishing Group, 2013), paper PTh3A.3. Export Citation BibTex Endnote (RIS) HTML Plain Text Citation alert Save article

Purpose: To evaluate the feasibility to treat lung cancer with very high‐ energy electrons (VHEE) by Monte Carlo (MC) simulations and to estimate the beam‐on time based on experimental dose measurements on an existing VHEE beam line. Methods: Manually optimized VHEE treatment plans for a simulated lung tumor were calculated for beam energies ranging from 50 to 150 MeV in the EGSnrc/DOSXYZnrc MC code. A state‐of‐the‐art RapidArc plan with a 6 MV photon beam was calculated for the same scenario using the Eclipse treatment planning system. The minimal electron beam energy matching the 6MV photon RapidArc plan was identified. VHEE dose from 50 and 70 MeV electrons was measured with Gafchromic EBT2 films on the Next Linear Collider Test Accelerator (NLCTA) beam line adapted to our experiments at the SLAC National Accelerator Laboratory. The experimental setup was modeled in the MCNPX code and the proton and neutron contributions to the total dose were quantified. The total treatment time for the lung case was estimated based on the parameters of the NLCTA beam line and experimental data. Results: For the selected clinical scenario, 75–100 MeV electron beams produced plans of comparably high quality to the best photon plans. The simulated NLCTA percentage depth dose curves and beam profiles at 6 mm depth generally agreed with measurements within 5% for both energies and all beam sizes. The dose contribution from protons and neutrons was negligible, accounting for less than 1×10−2% of the maximum total dose. Based on the beam line parameters and the measurements, a dose of 10 Gy to 95% of the 8 cc PTV could be in principle delivered in 1.3 s. Conclusions: Our results combining MC simulations with experimental measurements suggest that treatments of lung cancer with VHEE are feasible and very fast. We anticipate superior results with plan optimization.

The first ICFA Mini-workshop on Dielectric Laser Accelerators was held on September 15-16, 2011 at SLAC National Accelerator Laboratory. We present the results of the Workshop, and discuss the main conclusions of the Accelerator Applications, Photonics, and Laser Technologies working groups. Over 50 participants from 4 countries participated, discussing the state of the art in photonic structures, laser science, and nanofabrication as it pertains to laser-driven particle acceleration in dielectric structures. Applications of this new and promising acceleration concept to discovery science and industrial, medical, and basic energy sciences were explored. The DLA community is presently focused on making demonstrations of high gradient acceleration and a compatible attosecond injector source - two critical steps towards realizing the potential of this technology.

Recent technological advances has made possible the realization of the first laser-driven particle accelerator structure to be fabricated lithographically. However, a complete particle accelerator requires more than just accelerating elements. In this paper, we present a grating-based design for three other quintessential accelerator elements: the focusing structure, the deflecting structure, and the diagnostic structure.

We report on recent progress in the design, manufacture and testing of optical-scale accelerator structures made from silicon and silica. The potential of these structures for the development of extremely compact, efficient, and low cost accel erators producing attosecond electron pulses will be discussed, together with various possible applications.

The laser-damage threshold is a fundamental limit for any dielectric laser-driven accelerator and is set by the material of the structure. In this paper, we present a theoretical model of the laser damage mechanism, in comparison with experimental data on the damage threshold of silicon. Additionally, we present damage threshold measurement data of various optical materials, most of which have not been previously characterized in the picosecond-regime.

Echo-enabled harmonic generation free electron lasers hold great promise for the generation of fully coherent radiation in x-ray wavelengths. Here we report the first evidence of high harmonics from the echo-enabled harmonic generation technique in the realistic scenario where the laser energy modulation is comparable to the beam slice energy spread. In this experiment, coherent radiation at the seventh harmonic of the second seed laser is generated when the energy modulation amplitude is about 2-3 times the slice energy spread. The experiment confirms the underlying physics of echo-enabled harmonic generation and may have a strong impact on emerging seeded x-ray free electron lasers that are capable of generating laserlike x rays which will advance many areas of science.

A proof of principle fused-silica grating structure has been designed and fabricated for the purpose of direct laser acceleration of electrons. The optimal structure geometry was determined via 2D-FDTD and 3D-FEFD simulations to maximize the available acceleration gradient. The structure was fabricated with standard nanofabrication techniques, including optical lithography, reactive ion etching, and wafer bonding. Beam tests have been performed with the 60MeV beam at the Next Linear Collider Test Accelerator at SLAC, with successful demonstration of electron transmission through the micron-scale apertures.