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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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Confronting a set of Skyrme and $\chi _{EFT}$ predictions for the crust of neutron stars
With the improved accuracy of neutron star observational data, it is necessary to derive new equation of state where the crust and the core are consistently calculated within a unified approach. For this purpose we describe non-uniform matter in the crust of neutron stars employing a compressible liquid-drop model, where the bulk and the neutron fluid terms are given from the same model as the one describing uniform matter present in the core. We then generate a set of fifteen unified equations of state for cold catalyzed neutron stars built on realistic modelings of the nuclear interaction, which belongs to two main groups: the first one derives from the phenomenological Skyrme interaction and the second one from χEFT Hamiltonians. The confrontation of these model predictions allows us to investigate the model dependence for the crust properties, and in particular the effect of neutron matter at low density. Here, the new set of unified equations of state is available at the CompOSE repository.
Quark structure of the $\chi _{\mathrm{c}}(3P)$ and X(4274) resonances and their strong and radiative decays
We calculate the masses of χc(3P) states with threshold corrections in a coupled-channel model. The model was recently applied to the description of the properties of χc(2P) and χb(3P) multiplets (Ferretti and Santopinto in Phys Lett B 789:550, 2019]. We also compute the open-charm strong decay widths of the χc(3P) states and their radiative transitions. According to our predictions, the χc(3P) states should be dominated by the charmonium core, but they may also show small meson-meson components. The X(4274) is interpreted as a cc¯ χc1(3P) state. More information on the other members of the χc(3P) multiplet, as well as a more rigorous analysis of the X(4274)’s decay modes, are needed to provide further indications on the quark structure of the previous resonance.
ORNL-Chi-Geometry
Library for benchmarking neural network models on classification tasks for chirality detection in atomistic structures of organic compounds.
Cumulative $\chi^2$ Metric for VALID for ENDF/B-VII.1 and ENDF/B-VIII.0 in SCALE 6.3b9
Nuclear data testing is generally performed in a manner similar to validation: a series of critical benchmark experiments is modeled, and the differences between calculated and expected results are examined to understand the performance of a code and cross section set. This process is repeated for multiple sets of experiments with different transport codes and sometimes with different datasets. Occasionally, data processing differences are also important in understanding the differences in calculated results. Relevant experts then meet periodically to compare results and set priorities for improvement in the next round of data updates. This process has been largely effective, despite the confounding factors of different benchmark sets, application areas, sponsors, nationalities, and the resulting different priorities.
Comparing preliminary evaluations with Chi-Nu and CEA using the LAM model for the prior [Slides]
Abstract not provided.
Accomplishments from the LANL/LLNL Chi-Nu Project at LANSCE [Slides]
Abstract not provided.
New 238 U PFNS evaluation including Chi-Nu experimental data and ENDF/B-VIII.1b4 validation with LLNL pulsed spheres [Slides]
Abstract not provided.
Electron microscopy of single-stranded dna- circularity of phi chi -174 dna
Ring structure of single strand deoxyribonucleic acid shown by electron microscopy
The micrometeoroid satellite explorer xiii /1961 chi/
Observations of v.h.f.-bistatic-aurora-backscatter-communications on 145 Mc/s within Middle Europe and from Middle Europe to Great Britain and Scandinavia covering the period from 1957 to the beginning of 1963 are analyzed with respect to the probability of occurrence of these phenomena as a function of the magnetic dip angle and the degree of geomagnetic activity. An interpretation is given of the obtained results.
Identification atlas of molecular spectra 1- the alo alpha 2 sigma - chi 2 sigma blue-green system
Vibrational spectrum of blue-green system of aluminum oxide
Turbulent skin friction and heat-transfer charts adapted from the Spalding and Chi method
Local and average skin friction and heat transfer on flat plates in air - charts
Effect of autocorrelated observations on confidence sets based upon chi-square statistics
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On the use of the noncentral chi-square density function for the distribution of helicopter spectral estimates
A probability density function for the variability of ensemble averaged spectral estimates from helicopter acoustic signals in Gaussian background noise was evaluated. Numerical methods for calculating the density function and for determining confidence limits were explored. Density functions were predicted for both synthesized and experimental data and compared with observed spectral estimate variability.
Relative Band Oscillator Strengths for Carbon Monoxide: Alpha (1)Pi-Chi (1)Sigma(+) Transitions
Band oscillator strengths for CO transitions between the electronic states A (l)Pi and X(1)Sigma(+) were measured via absorption with a synchrotron radiation source. When referenced to the well-characterized (5,0) band oscillator strength, our relative values for the (7,0) to (11,0) bands are most consistent with the recent experiments of Chan et al. and the theoretical predictions of Kirby & Cooper. Since the results from various laboratory techniques and theory now agree, analyses of interstellar CO based on absorption from A-X bands are no longer hindered by uncertainties in oscillator strength.
High Resolution Emission Spectroscopy of the Alpha Pi-1 - Chi Sigma-1(+) Fourth Positive Band System of CO from Electron Impact
We report electron-impact induced fluorescence spectra [300 mA full width at half maximum (FWHM)] of CO for 20 and 100 eV impact energies of the spectral region of 1300 to 2050 A and high resolution spectra (FWHM) of the v'=5 to v"=l and the v'=3 to v"=O bands showing that the rotational structure of the band system are modeled accurately. The excitation function of the (0,1) band (1597 A) was measured from electron impact in the energy range from threshold to 750 eV and placed on an absolute scale from modem calibration standards.
Absolute Rovibrational Intensities for the Chi(sup 1)Sigma(sup +) v=3 <-- 0 Band of (12)C(16)O Obtained with Kitt Peak and BOMEM FTS Instruments
This work was initiated to compare absolute line intensities retrieved with the Kitt Peak FTS (Fourier Transform Spectrometer) and Ames BOMEM FTS. Since thermal contaminations can be a problem using the BOMEM instrument if proper precautions are not taken it was thought that measurements done at 6300 per cm would more easily result in satisfactory intercomparisons. Very recent measurements of the CO 3 <-- 0 band fine intensities confirms results reported here that the intensities listed in HITRAN (High Resolution Molecular Absorption Database) for this band are on the order of six to seven percent too low. All of the infrared intensities in the current HITRAN tabulation are based on the electric dipole moment function reported fifteen years ago. The latter in turn was partly based on intensities for the 3 <-- 0 band reported thirty years ago. We have, therefore, redetermined the electric dipole moment function of ground electronic state CO.
Fourier Transform Infrared Emission and Rotational Spectra of Chi super 2 Sigma super+States of SrH and SrD
This paper describes observations of the rotation-vibration emission spectrum of SrH using a high-resolution Bruker IFS 120 spectrometer.