Correlating hot-electron preheat from the two-plasmon decay instability to ρR degradation for direct-drive implosions on OMEGA
Focused experiments were performed with the goal of isolating the impact of hot-electron preheat on compression in deuterium–tritium (DT) layered, direct-drive implosions on OMEGA. Preheat from the hot-electrons generated by two-plasmon–decay (TPD) activity was varied through the incident laser intensity, with the total preheat energy deposited into unablated DT fuel being inferred using hard x-ray measurements. Results show a clear correlation between the inferred preheat levels and ρR degradation that is consistent with a derived, 1D preheat model. A fit to the results also provides an estimated range of ρR degradation from non-preheat sources for the adiabat ≈5implosions used in this study. A follow-up study using targets containing Si-doped (5.5%) CH ablators (CHSi) demonstrated results consistent with mid-Z dopants mitigating TPD activity by showing these targets had almost no ρR degradation as the laser intensity was increased up to levels previously considered damaging.
Authors
- V. N. Goncharov (ORCID: https://orcid.org/0000-0003-2730-1666)
- C. Stöeckl (ORCID: https://orcid.org/0000-0001-5375-5800)
- S. P. Regan (ORCID: https://orcid.org/0000-0001-6359-7172)
- C. J. Forrest (ORCID: https://orcid.org/0000-0002-6288-322X)
- M. J. Rosenberg (ORCID: https://orcid.org/0000-0002-9924-304X)
- T. J. B. Collins (ORCID: https://orcid.org/0000-0002-2614-2459)
- L. Ceurvorst (ORCID: https://orcid.org/0000-0002-4215-3326)
- V. Gopalaswamy (ORCID: https://orcid.org/0000-0002-8013-9314)
- K. Churnetski (ORCID: https://orcid.org/0000-0003-3337-2647)
- R. P. Bahukutumbi (ORCID: https://orcid.org/0000-0001-5473-1632)
- A. Lees (ORCID: https://orcid.org/0000-0003-4573-4035)
- R. Betti (ORCID: https://orcid.org/0000-0001-8742-0304)
- D. Cao (ORCID: https://orcid.org/0000-0003-1085-2322)
- W. Theobald (ORCID: https://orcid.org/0000-0003-0414-9999)
- A. R. Christopherson (ORCID: https://orcid.org/0000-0003-3578-635X)
- D. Patel
Institutions
- Energetics (United States) (US)
- University of Rochester (US)
Publication Details
- Journal
- Physics of Plasmas
- Published
- 2025-09-01
- DOI
- https://doi.org/10.1063/5.0281270
- Primary Topic
- Laser-Plasma Interactions and Diagnostics
- Type
- article
- Field-Weighted Citation Impact
- 0.00
Funders
- U.S. Department of Energy
- University of Rochester
- National Nuclear Security Administration