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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Interplay of thermal and nonthermal effects in x-ray-induced ultrafast melting
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Using Diffuse Scattering to Observe X-Ray-Driven Nonthermal Melting
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Light-Driven Raman Coherence as a Nonthermal Route to Ultrafast Topology Switching in a Dirac Semimetal
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Fractal, Logarithmic, and Volume-Law Entangled Nonthermal Steady States via Spacetime Duality
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Exploring the Spectral Signatures of Inner-shell Excitation Mechanisms in Nonthermal Z-pinch Plasmas.
Abstract not provided.
Recent Progress on the Study of Nonthermal X-rays in High Energy Density Z-pinch Plasmas.
Abstract not provided.
Monte Carlo Radiation Transport Simulation of Nonthermal X-ray Fluorescence in a MagLIF Plasma Produced on Z.
Abstract not provided.
Nonthermal Ionization of Kilonova Ejecta: Observable Impacts
The characteristic rapid rise and decline at optical wavelengths of a kilonova is the product of the low ejecta mass (≲0.05 M ⊙ ) and high ejecta velocity (≳0.1c). We show that, even at very early times (≲2 days), regions of ejecta fall below critical density and temperature thresholds at which nonlocal thermodynamic equilibrium (NLTE) effects become important. Here, we present an approximate method for calculating the ionization state of the ejecta that accounts for the NLTE impact of high-energy electrons produced in the beta decay of freshly synthesized r-process elements. We find that incorporating ionization from high-energy electrons produces an “inverted” and “blended” ionization structure, where the most highly ionized species are located in the fastest moving homologous ejecta, and multiple ionization states coexist. In radiation transport calculations, the higher degree of ionization reduces line blanketing in optical bands, leading to improved agreement with the light-curve properties of AT 2017gfo, such as the duration, decay rates, brightness, and colors. Our quasi-NLTE implementation helps to alleviate tensions in kilonova modeling: for high-velocity (∼0.3 c) ejecta components, our models require less mass for a given peak brightness in optical bands, by as much as a factor of 3; our models can explain the presence of observed features associated to Sr II, W III, Se III, and Te III under conditions where LTE models would predict only neutral species; and we naturally predict the coexistence of species like Sr II and Ce III without the need for fine-tuning of the ejecta properties.
Unveiling Properties of the Nonthermal X-Ray Production in the Gamma-Ray Binary LS 5039 Using the Long-term Pattern of Its Fast X-Ray Variability
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NuSTAR Observations of Abell 665 and 2146: Constraints on Nonthermal Emission
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Nonthermal Hydrogen Loss at Mars: Contributions of Photochemical Mechanisms to Escape and Identification of Key Processes
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Are Nonthermal Velocities in Active Region Coronal Loops Anisotropic?
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Survey of certain nonthermal methods of decontamination and sterilization
Ionizing radiation techniques for spacecraft decontamination and sterilization
On the relationship between recent measurements of cosmic ray electrons, nonthermal radio emission from the galaxy and the solar modulation of cosmic rays
Primary cosmic ray electron and galactic radio emission effects on electron intensity near earth
Nonthermal electrons and high-frequency waves in the upstream solar wind. II - Analysis and interpretation
Suprathermal electron beam induced HF wave instability in solar wind upstream from earth bow shock, interpreting OGO 5 observations
Possible explanation for nonthermal radio noise from binary stars.
Radio emission from the binary stars alpha-Sco, beta-Per, and beta-Lyr is interpreted as due to the mass exchange between the components. The electrons in the inflowing stream excite plasma waves near the surface of the receptor star, and these waves generate radio emission. Crude predictions of radio frequency, intensity, and timescales of variation seem compatible with current observations.
Physics of compact nonthermal sources. III - Energetic considerations
The energy content of the compact incoherent electron-synchrotron sources 3C 84, 3C 120, 3C 273, 3C 279, 3C 454.3, CTA 102, 3C 446, PKS 2134+004, VRO 42.22.01 and OJ 287 is calculated on the assumption that the low-frequency turnovers in the radio spectrum are due to self-absorption and that the electron distribution is isotropic. The dependence of the source parameters on various modifications of the standard assumptions is determined. These involve relativistic motions, alternate explanations for the low-frequency turnover, proton-synchrotron radiation, and distance to the source. The canonical interpretation is found to be accurate in many respects; some of the difficulties and ways of dealing with them are discussed in detail.