Laser-based ultrasound detects defect-producing features in metal 3D printing

Lawrence Livermore National Laboratory (LLNL) researchers have developed a new all-optical ultrasound technique capable of performing on-demand characterization of melt tracks and detecting formation of defects in a popular metal 3D printing process. In a paper published by Scientific Reports, Lab researchers propose a diagnostic using surface acoustic waves (SAW), generated by laser...

Researchers update measurement ratios key for inertial confinement fusion experiments

Lawrence Livermore National Laboratory (LLNL) researchers have refined the measurement of the gamma (γ)-to-neutron branching ratio in deuterium-tritium (D-T) fusion reactions. This reaction is a viable candidate for fusion energy, as it is known to have the largest cross section at center-of-mass energies below 500 keV. There are different branches of this reaction. These include an...

White House summit celebrates fusion milestones, discusses 'bold' 10-year plan for commercialization

Recent scientific advancements in fusion, combined with increasing private investments and the urgent need to address climate change, mean the “time is now” for accelerating fusion energy commercialization, fusion experts said at a White House summit on March 17. Hosted by the White House Office of Science and Technology Policy (OSTP) and the U.S. Department of Energy (DOE), the first...

Holographic plasma lenses for ultra-high-power lasers

In the National Ignition Facility (NIF), the world’s highest-energy laser system, a complex series of glass optics — including amplifiers, mirrors, wavelength converters and focusing lenses — strengthens and guides the laser light to its destination. Over the years, researchers have developed and refined these optics so they can withstand the intense energies generated by NIF’s powerful laser...

LLNL constructing high-power laser for new experimental facility at SLAC

Lawrence Livermore National Laboratory’s decades of leadership in developing high-energy lasers is being tapped to provide a key component of a major upgrade to SLAC National Accelerator Laboratory’s Linac Coherent Light Source (LCLS). Over the next several years, LLNL’s Advanced Photon Technologies (APT) program will design and construct one of the world’s most powerful petawatt...

NIF helps unravel mysteries of heat conduction in galaxy clusters

An international team led by scientists from the University of Oxford Department of Physics, the University of Rochester and the University of Chicago turned to Lawrence Livermore National Laboratory’s (LLNL’s) National Ignition Facility (NIF) to help unravel the inner workings of heat conduction in clusters of galaxies — the largest structures in the universe. These clusters are made of...

LLNL scientists confirm thermonuclear fusion in a sheared-flow Z-pinch

In findings that could help advance another “viable pathway” to fusion energy, research led by Lawrence Livermore National Laboratory (LLNL) physicists has proven the existence of neutrons produced through thermonuclear reactions from a sheared-flow stabilized Z-pinch device. The researchers used advanced computer modeling techniques and diagnostic measurement devices honed at the Lab to...

Understanding hot-spot conditions in experiments at the National Ignition Facility

Research conducted at Lawrence Livermore National Laboratory (LLNL) describes a validation exercise for simple models used to understand hot-spot conditions reached in an implosion, which find good agreement when compared to a set of simulations. Progress toward ignition requires accurately diagnosing current conditions and assessing proximity metrics for implosion experiments at LLNL...

Researchers take closer look at stimulated Brillouin scattering

A major cost of running the National Ignition Facility (NIF) is managing and mitigating laser-induced damage to optics as the laser beams propagate to the target.  Another damage mechanism stems from stimulated Brillouin scattering (SBS) as light travels back from the target and with nearly the same wavelength as the incoming light. This SBS has the potential to cause additional damage...

‘Science on Saturday’ lecture to highlight nuclear fusion

WHO: Lawrence Livermore National Laboratory (LLNL) scientists Derek Mariscal and Dave Schlossberg, along with teacher Tom Shefler of Granada High School, will present “Bringing Star Power to Earth: Harnessing Nuclear Fusion,” the third lecture in the 2022 virtual Science on Saturday series that highlights Energy and the Environment. WHAT: This presentation will provide an overview...

Understanding the mystery of why particles cluster in turbulent flows

New research conducted at Lawrence Livermore National Laboratory (LLNL) analyzes three-dimensional particle-laden, isotropic turbulence to develop an understanding of inertial particle dynamics from a kinetic energy perspective. Particle-laden flows are found in a variety of applications such as rain droplets in clouds, wind-driven sand dune sprays, fluidized bed reactors and soot...

Nature paper describes the target and laser designs that achieved a burning plasma at Lawrence Livermore

One of the last remaining milestones in fusion research before attaining ignition and self-sustaining energy production is creating a burning plasma. In this state, the fusion reactions themselves become the dominant source of heating in the plasma, but do not yet overcome all mechanisms of energy loss. A burning plasma state was achieved on November 2020 and February 2021 at Lawrence...

Nature paper chronicles how researchers achieved burning plasma regime for the first time in a laboratory experiment

After decades of fusion research, a burning plasma state was achieved on November 2020 and February 2021 at Lawrence Livermore National Laboratory’s National Ignition Facility (NIF), the world’s most energetic laser. Obtaining a burning plasma is a critical step toward self-sustaining fusion energy. A burning plasma is one in which the fusion reactions themselves are the primary source...

LLNL thin film engineer named fellow of SPIE

Lawrence Livermore National Laboratory’s (LLNL) Christopher Stolz has been elected as a fellow of SPIE, the international society for optics and photonics. Stolz, an associate program manager in charge of the National Ignition Facility (NIF) optics supply, has worked at LLNL in the laser directorate as a thin film engineer for more than 30 years; first in AVLIS and then NIF. “I...

Research looks at ‘piston-model’ to understand impacts of asymmetry on ICF implosions

New research conducted at Lawrence Livermore National Laboratory (LLNL) explores the expansion of a classical mechanics model, which has been useful for understanding asymmetries in inertial confinement fusion (ICF) implosions, from a two-piston to a six-piston model to capture higher-mode asymmetries. The work is featured in the Physics of Plasmas. LLNL authors included Omar...

Ironing out the interiors of exoplanets

The discovery of more than 4,500 extra-solar planets has created a need for modelling their interior structure and dynamics. As it turns out, iron plays a key role. Lawrence Livermore National Laboratory (LLNL) scientists and collaborators have used lasers at the National Ignition Facility to experimentally determine the high-pressure melting curve and structural properties of pure iron up...

Physicist Omar Hurricane receives prestigious Edward Teller Award

Omar Hurricane, chief scientist for the Lawrence Livermore National Laboratory inertial confinement fusion (ICF) program, is a recipient of the 2021 Edward Teller Award. The Fusion Energy Division of the American Nuclear Society (ANS) presented the award to Hurricane for his “visionary scientific insights and leadership of National Ignition Facility (NIF) experiments resulting in the...

Research looks at entropy generation from hydrodynamic mixing in ICF experiments

Research conducted at Lawrence Livermore National Laboratory (LLNL) is taking a closer look at entropy — the measure of internal energy per unit temperature that is unavailable for doing useful work — in experiments at the National Ignition Facility (NIF). Work by LLNL physicist Peter Amendt is highlighted as an Editor’s Pick in Physics of Plasma, showing that an added entropy increase...

New research looks at process of magnetic flux generation in ICF implosions

Lawrence Livermore National Laboratory (LLNL) researchers now have a better understanding on how strong the magnetic fields are in an inertial confinement fusion (ICF) implosion at the National Ignition Facility (NIF), the world’s most energetic laser. The researchers described their findings a paper published in Physics of Plasmas with LLNL scientists Chris Walsh serving as lead...

Three LLNL scientists honored as APS fellows

Three Lawrence Livermore National Laboratory (LLNL) physicists have been selected as 2021 fellows of the American Physical Society (APS). The new fellows represent a selection of physics expertise, ranging from intense laser-matter interactions and inertial fusion energy science to leading the development of edge simulation models and codes to pioneering new regimes of warm dense matter...