Search NASA⌕ Search
Home/Archive/DOE OSTI

DOE OSTI · 2584400

Approaching hydro-equivalent ignition in laser direct-drive via target design optimization using novel statistical modeling

Lees, A. [University of Rochester, NY (United States)] (ORCID:0000000345734035)·Betti, R. [University of Rochester, NY (United States)] (ORCID:0000000187420304)·Gopalaswamy, V. [University of Rochester, NY (United States)] (ORCID:0000000280139314)·Knauer, J. P. [University of Rochester, NY (United States)] (ORCID:0009000990972885)·Ceurvorst, L. A. [University of Rochester, NY (United States)] (ORCID:0000000242153326)·Patel, D. [University of Rochester, NY (United States)]·Ejaz, R. [University of Rochester, NY (United States)] (ORCID:0009000241322957)·Anderson, K. S. [University of Rochester, NY (United States)] (ORCID:0000000292484545)·Bauer, K. A. [University of Rochester, NY (United States)] (ORCID:0000000255056808)·Bonino, M. J. [University of Rochester, NY (United States)]·Cao, D. [University of Rochester, NY (United States)] (ORCID:0000000310852322)·Churnetski, K. [University of Rochester, NY (United States)] (ORCID:0000000333372647)·Collins, T. J. [University of Rochester, NY (United States)] (ORCID:0000000226142459)·Farmakis, P. S. [University of Rochester, NY (United States)] (ORCID:000000026520355X)·Forrest, C. J. [University of Rochester, NY (United States)] (ORCID:000000026288322X)·Goncharov, V. N. [University of Rochester, NY (United States)] (ORCID:0000000327301666)·Harding, D. R. [University of Rochester, NY (United States)]·Heuer, P. V. [University of Rochester, NY (United States)] (ORCID:0000000150506606)·Igumenshchev, I. V. [University of Rochester, NY (United States)] (ORCID:0000000154958503)·Janezic, R. T. [University of Rochester, NY (United States)] (ORCID:0000000292929321)·Regan, S. P. [University of Rochester, NY (United States)] (ORCID:0000000163597172)·Rosenberg, M. J. [University of Rochester, NY (United States)] (ORCID:000000029924304X)·Sampat, S. [University of Rochester, NY (United States)] (ORCID:0000000275779309)·Shah, R. C. [University of Rochester, NY (United States)] (ORCID:0000000169939882)·Stoeckl, C. [University of Rochester, NY (United States)] (ORCID:0000000153755800)·Thomas, C. A. [University of Rochester, NY (United States)] (ORCID:0000000231312491)·Woo, K. M. [University of Rochester, NY (United States)] (ORCID:0000000211243871)·Gatu Johnson, M. [Massachusetts Institute of Technology, Cambridge, MA (United States)] (ORCID:0000000223831275)·Li, C. K. [Massachusetts Institute of Technology, Cambridge, MA (United States)] (ORCID:0000000269194881)·Frenje, J. A. [Massachusetts Institute of Technology, Cambridge, MA (United States)] (ORCID:0000000168460378)·Wink, C. W. [Massachusetts Institute of Technology, Cambridge, MA (United States)] (ORCID:0000000238186715)
View original source ↗Read source document ↗Export metadata ↓

Abstract

Laser direct-drive offers significant advantages in terms of target simplicity, improved energy coupling, and large fuel masses over indirect drive. However, performance degradations from hydrodynamic and laser-plasma instabilities seeded and driven by the direct illumination pose limitations on the parameter space available for achieving ignition. In this paper, new design improvements are identified to forge a path forward for a hydro-equivalent ignition demonstration. The first is related to a new formulation of the statistical model (SM) used to accurately predict target performance directly from input parameters such as laser pulse shape and target specifications. This new SM formulation provides direct guidance on target dimensions and laser beam-to-target radius to achieve the highest fusion yield on the OMEGA laser. The second improvement comes from cooling the deuterium–tritium (DT) ice layer below the triple point right before shot time leading to lower DT vapor densities and higher convergence. Guided by these design improvements, a Bayesian optimization algorithm was used to design an implosion that is predicted to closely approach a Lawson triple product that hydrodynamically scales to ignition if equivalent laser–target coupling is achieved at laser energies typical of the National Ignition Facility.

Explore related subjects

DeuteriumGaussian processesLasersNuclear fusionOptimization algorithmsPlasma instabilitiesPlasma physicsStatistical analysisTritium

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Lees, A. [University of Rochester, NY (United States)] (ORCID:0000000345734035), Betti, R. [University of Rochester, NY (United States)] (ORCID:0000000187420304), Gopalaswamy, V. [University of Rochester, NY (United States)] (ORCID:0000000280139314), Knauer, J. P. [University of Rochester, NY (United States)] (ORCID:0009000990972885), Ceurvorst, L. A. [University of Rochester, NY (United States)] (ORCID:0000000242153326), Patel, D. [University of Rochester, NY (United States)], Ejaz, R. [University of Rochester, NY (United States)] (ORCID:0009000241322957), Anderson, K. S. [University of Rochester, NY (United States)] (ORCID:0000000292484545), Bauer, K. A. [University of Rochester, NY (United States)] (ORCID:0000000255056808), Bonino, M. J. [University of Rochester, NY (United States)], Cao, D. [University of Rochester, NY (United States)] (ORCID:0000000310852322), Churnetski, K. [University of Rochester, NY (United States)] (ORCID:0000000333372647), Collins, T. J. [University of Rochester, NY (United States)] (ORCID:0000000226142459), Farmakis, P. S. [University of Rochester, NY (United States)] (ORCID:000000026520355X), Forrest, C. J. [University of Rochester, NY (United States)] (ORCID:000000026288322X), Goncharov, V. N. [University of Rochester, NY (United States)] (ORCID:0000000327301666), Harding, D. R. [University of Rochester, NY (United States)], Heuer, P. V. [University of Rochester, NY (United States)] (ORCID:0000000150506606), Igumenshchev, I. V. [University of Rochester, NY (United States)] (ORCID:0000000154958503), Janezic, R. T. [University of Rochester, NY (United States)] (ORCID:0000000292929321), Regan, S. P. [University of Rochester, NY (United States)] (ORCID:0000000163597172), Rosenberg, M. J. [University of Rochester, NY (United States)] (ORCID:000000029924304X), Sampat, S. [University of Rochester, NY (United States)] (ORCID:0000000275779309), Shah, R. C. [University of Rochester, NY (United States)] (ORCID:0000000169939882), Stoeckl, C. [University of Rochester, NY (United States)] (ORCID:0000000153755800), Thomas, C. A. [University of Rochester, NY (United States)] (ORCID:0000000231312491), Woo, K. M. [University of Rochester, NY (United States)] (ORCID:0000000211243871), Gatu Johnson, M. [Massachusetts Institute of Technology, Cambridge, MA (United States)] (ORCID:0000000223831275), Li, C. K. [Massachusetts Institute of Technology, Cambridge, MA (United States)] (ORCID:0000000269194881), Frenje, J. A. [Massachusetts Institute of Technology, Cambridge, MA (United States)] (ORCID:0000000168460378), Wink, C. W. [Massachusetts Institute of Technology, Cambridge, MA (United States)] (ORCID:0000000238186715). 2025-07-02. Approaching hydro-equivalent ignition in laser direct-drive via target design optimization using novel statistical modeling. https://doi.org/10.1063/5.0274635

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related reports

DOE OSTI2026

Growth of deuterium supersaturated surface layer with increasing ion flux and fluence in plasma-exposed tungsten

Deuterium supersaturated surface layer (DSSL) in tungsten, a few nm thick layer exhibiting extremely high deuterium content (> 5%), has been studied as a function of deuterium plasma ion flux and fluence. Tungsten samples were exposed at 400 K and deuterium ion energy of ∼ 60 eV. The deuterium ion flux spanned over an order of magnitude, being 7.3 × 10 20 , 4.2 × 10 21 , and 3.8 × 10 22 D/m 2 . The fluence ranged from 3.4 × 1024 to 3.4 × 1025 D/m2. The samples and their deuterium content were analyzed by nuclear reaction analysis (NRA), scanning transmission electron microscopy (STEM), and thermal desorption spectroscopy (TDS). The largest thickness of DSSL was found to be around 10.5 nm and was observed in the case of the highest exposure flux and fluence, whereas the layer was only about 3.8 nm thick in the case of the lowest value of the two parameters. The thickness of the DSSL was found to monotonically increase with both deuterium flux and fluence. Finally, similar to the thickness, the estimated D concentration seems to follow the same trend, increasing from the lowest value of around 3 at.% to the highest value of around 5 at.%.

Deuterium↗
DOE OSTI2026

An ultra-fast method for generating synthetic down-scattered neutron data for inertial confinement fusion implosions

In inertial confinement fusion experiments at the National Ignition Facility, asymmetries are probed by a variety of neutron diagnostics, including neutron imaging systems, real-time neutron activation diagnostics (RTNADs), and neutron spectrometers. It is often useful to generate synthetic data based on these diagnostics to validate and tune models. However, current methods of doing so using Monte Carlo particle tracing are time-consuming. In this paper, an ultra-fast method is presented for generating synthetic neutron images, RTNAD data, and spectrometry data using line integrals and 3D convolutions. While it does not contain as much physics as particle tracing codes, it is thousands of times faster and produces nearly identical data. This enables analysis techniques that depend on generating large amounts of synthetic data, which will prove very useful for the study of asymmetries going forward.

Deuterium↗
DOE OSTI2026

Difference in neoclassical edge flows between strongly negative and positive triangularities in the XGC gyrokinetic simulation

The neoclassical baseline study of a strongly negative triangularity (NT) plasma and the corresponding positive triangularity (PT) plasma is performed using the edge-specialized, total-f gyrokinetic code (X-point Gyrokinetic Code, XGC). A DIII-D-like plasma is used, based on the negative triangularity discharge of DIII-D #193 793. An artificial positive triangularity (PT) equilibrium has been constructed to compare the edge rotation physics at the same triangularity strength but with opposite sign, while keeping the same elongation and other geometric parameters. Carbon(6+) ions are added to the deuterium plasma at an experimentally relevant level. By using the experimental profile of carbon toroidal rotation profile as an input, XGC finds that the deuteron rotation is significantly different from the carbon rotation at the inboard and outboard midplanes, mostly caused by the difference in the Pfirsch–Schlüter rotation. More importantly, a significant difference in the X-point orbit loss physics, thus the rotation source, is found between the positive and negative triangularity equilibrium models. However, it is also found that the agreement between the present neoclassical simulation and the experimental NT data is validated only within the middle of the pedestal slope, indicating the importance of edge turbulence. Finally, this study could establish a baseline for the multiphysics, multiscale studies that include turbulence of negative triangularity plasmas.

Deuterium↗