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Systematic measurements of opacity dependence on temperature density and atomic number at stellar interior conditions

Bailey, James E.; Nagayama, Taisuke N.; Loisel, Guillaume P.; Rochau, G.A.; Blancard, C.; Colgan, J.; Cosse, Ph; Faussurier, G.; Fontes, C.J.; Gilleron, F.; Golovkin, I.; Hansen, Stephanie B.; Iglesias, C.A.; Kilcrease, D.P.; Macfarlane, Joseph J.; Mancini, Roberto C.; Nahar, S.N.; Orban, C.; Pain, J.C.; Pradhan, A.K.; Sherrill, M.; Wilson, B.G.

Abstract not provided.

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TYPE Conference Poster YEAR 2017
OSTIOSTI

Comment on "Large Enhancement in High-Energy Photoionization of Fe XVII and Missing Continuum Plasma Opacity"

Physical Review Letters

Blancard, C.; Colgan, J.; Cosse, Ph; Faussurier, G.; Fontes, C.J.; Gilleron, F.; Golovkin, I.; Hansen, Stephanie B.; Iglesias, C.A.; Kilcrease, D.P.; Macfarlane, J.J.; Pain, J.C.; Sherrill, M.; Wilson, B.G.

Recent R-matrix calculations claim to provide a significant enhancement in the opacity of Fe XVII due to atomic core excitations and assert that this enhancement is consistent with recent measurements of higher-than-predicted iron opacities. Here this comment shows that the standard opacity models which have already been directly compared with experimental data produce photon absorption cross-sections for Fe XVII that are effectively equivalent to the R-matrix opacities reported in.

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TYPE Journal Article YEAR 2016
DOIOSTIScopus

Systematic measurements of opacity dependence on temperature density and atomic number at stellar interior conditions

Nagayama, Taisuke N.; Bailey, James E.; Loisel, Guillaume P.; Rochau, G.A.; Blancard, C.; Colgan, J.; Cosse, Ph; Faussurier, G.; Fontes, C.J.; Golovkin, I.; Hansen, Stephanie B.; Iglesias, C.A.; Kilcrease, D.P.; Macfarlane, J.J.; Mancini, Roberto C.; Nahar, S.N.; Orban, C.; Pradham, A.K.; Sherrill, M.; Wilson, B.G.

Abstract not provided.

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TYPE Conference Poster YEAR 2016
OSTI

Developing a Pre-Heat Platform for MagLIF with Z-Beamlet

Geissel, Matthias G.; Awe, Thomas J.; Bliss, David E.; Campbell, Edward M.; Gomez, Matthew R.; Glinsky, Michael E.; Harding, Eric H.; Harvey-Thompson, Adam J.; Hansen, Stephanie B.; Jennings, Christopher A.; Kimmel, Mark W.; Knapp, Patrick K.; Lewis, Sean M.; Peterson, Kyle J.; Schollmeier, Marius; Schwarz, Jens S.; Sefkow, Adam B.; Shores, Jonathon S.; Sinars, Daniel S.; Slutz, Stephen A.; Smith, Ian C.; Speas, Christopher S.; Vesey, Roger A.; Porter, John L.; Rochau, G.A.

Abstract not provided.

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TYPE Conference Poster YEAR 2016
OSTIOSTI

Systematic measurements of opacity dependence on temperature density and atomic number at stellar interior conditions

Bailey, James E.; Nagayama, Taisuke N.; Loisel, Guillaume P.; Rochau, G.A.; Blancard, C.; Colgan, J.; Cosse, Ph; Faussurier, G.; Fontes, C.J.; Gilleron, F.; Golovkin, I.; Hansen, Stephanie B.; Iglesias, C.A.; Kilcrease, D.P.; Macfarlane, Joseph J.; Mancini, Roberto C.; Nahar, S.N.; Orban, C.; Pain, J.C.; Pradhan, A.K.; Sherrill, M.; Wilson, B.G.

Abstract not provided.

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TYPE Conference Poster YEAR 2016
OSTIOSTI

Investigating the effect of adding an on-axis jet to Ar gas puff Z pinches on Z

Physics of Plasmas

Harvey-Thompson, Adam J.; Jennings, Christopher A.; Jones, Brent M.; Ampleford, David A.; Lamppa, Derek C.; Coverdale, Christine A.; Cuneo, M.E.; Hansen, Stephanie B.; Jones, Michael J.; Moore, Nathan W.; Rochau, G.A.; Apruzese, John P.; Giuliani, John L.; Thornhill, John W.

Double-shell Ar gas puff implosions driven by 16.5±0.5 MA on the Z generator at Sandia National Laboratories are very effective emitters of Ar K-shell radiation (photon energy >3 keV), producing yields of 330 ± 9% kJ (B. Jones et al., Phys. Plasmas, 22, 020706, 2015). In addition, previous simulations and experiments have reported dramatic increases in K-shell yields when adding an on-axis jet to double shell gas puffs for some configurations.

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TYPE Journal Article YEAR 2016
DOIOSTIDOIOSTI

Neutron Diagnostic Development fro the Z Accelerator

Hahn, Kelly D.; Chandler, Gordon A.; Ruiz, Carlos L.; Jones, Brent M.; Gomez, Matthew R.; Knapp, Patrick K.; Sefkow, Adam B.; Hansen, Stephanie B.; Schmit, Paul S.; Harding, Eric H.; Norris, Edward T.; Torres, Jose A.; Cooper, Gary W.; Styron, Jedediah D.; Glebov, V.Y.; Frenje, J.; Lahmann, B.; Gatu-Johnson, M.; Seguin, F.; Petrasso, R.; Fittinghoff, D.; May, M.; Snyder, L.; Moy, K.; Buckles, R.

Abstract not provided.

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TYPE Conference Poster YEAR 2016
OSTIOSTI

A non-LTE analysis of high energy density Kr plasmas on Z and NIF

Physics of Plasmas

Dasgupta, A.; Clark, R.W.; Ouart, N.; Giuliani, J.; Velikovich, A.; Ampleford, David A.; Hansen, Stephanie B.; Jennings, Christopher A.; Harvey-Thompson, Adam J.; Jones, Brent M.; Flanagan, Timothy M.; Bell, Kate S.; Apruzese, J.P.; Fournier, K.B.; Scott, H.A.; May, M.J.; Barrios, M.A.; Colvin, J.D.; Kemp, G.E.

Multi-keV X-ray radiation sources have a wide range of applications, from biomedical studies and research on thermonuclear fusion to materials science and astrophysics. The refurbished Z pulsed power machine at the Sandia National Laboratories produces intense multi-keV X-rays from argon Z-pinches, but for a krypton Z-pinch, the yield decreases much faster with atomic number ZA than similar sources on the National Ignition Facility (NIF) laser at the Lawrence Livermore National Laboratory. To investigate whether fundamental energy deposition differences between pulsed power and lasers could account for the yield differences, we consider the Kr plasma on the two machines. The analysis assumes the plasma not in local thermodynamic equilibrium, with a detailed coupling between the hydrodynamics, the radiation field, and the ionization physics. While for the plasma parameters of interest the details of krypton's M-shell are not crucial, both the L-shell and the K-shell must be modeled in reasonable detail, including the state-specific dielectronic recombination processes that significantly affect Kr's ionization balance and the resulting X-ray spectrum. We present a detailed description of the atomic model, provide synthetic K- and L-shell spectra, and compare these with the available experimental data from the Z-machine and from NIF to show that the K-shell yield behavior versus ZA is indeed related to the energy input characteristics. This work aims at understanding the probable causes that might explain the differences in the X-ray conversion efficiencies of several radiation sources on Z and NIF.

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TYPE Journal Article YEAR 2016
DOIOSTIScopus

Overview of Neutron diagnostic measurements for MagLIF Experiments on the Z Accelerator

Hahn, Kelly D.; Chandler, Gordon A.; Ruiz, Carlos L.; Cooper, Gary W.; Gomez, Matthew R.; Slutz, Stephen A.; Sefkow, Adam B.; Sinars, Daniel S.; Hansen, Stephanie B.; Knapp, Patrick K.; Schmit, Paul S.; Harding, Eric H.; Jennings, Christopher A.; Awe, Thomas J.; Geissel, Matthias G.; Rovang, Dean C.; Torres, Jose A.; Bur, James A.; Cuneo, M.E.; Glebov, V.Y.; Harvey-Thompson, Adam J.; Hess, Mark H.; Johns, Owen J.; Jones, Brent M.; Lamppa, Derek C.; Lash, Joel S.; Martin, Matthew; McBride, Ryan D.; Peterson, Kyle J.; Porter, John L.; Reneker, Joseph R.; Robertson, Grafton K.; Rochau, G.A.; Savage, Mark E.; Smith, Ian C.; Styron, Jedediah D.; Vesey, Roger A.

Abstract not provided.

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TYPE Presentation YEAR 2016
OSTI

Measuring the radiative properties of astrophysical matter using the Z x-ray source

Bailey, James E.; Nagayama, Taisuke N.; Loisel, Guillaume P.; Rochau, G.A.; Blancard, C.; Colgan, J.; Cosse, Ph; Faussurier, G.; Fontes, C.J.; Gilleron, F.; Golovkin, I.; Hansen, Stephanie B.; Iglesias, C.A.; Kilcrease, D.P.; Macfarlane, Joseph J.; Mancini, Roberto C.; Nahar, S.N.; Orban, C.; Pain, J.C.; Pradhan, A.K.; Sherrill, M.; Wilson, B.G.

Abstract not provided.

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TYPE Conference Poster YEAR 2016
OSTI
Results 151–175 of 352
Results 151–175 of 352