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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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Utilizing a crossed electron beam-molecular beam collision geometry, mass spectra of C(sub 60) and C(sub 70) ions have been obtained for an electron impact energy range of 20 eV to 600 eV.
Molecular nitrogen and oxygen ions colliding with atomic sodium examined in crossed-beam experiment for resonance charge transfers
Consistent field Monte Carlo method calculation for collision effect on electron-ion diode characteristics and for hard sphere electron- neutral collision effect for monoenergetic- thermionic emission
Thermal escape of neutral hydrogen and distribution in Earth thermosphere, noting collision in transition regions
Low collision energy charge transfer and dissociative charge transfer between rare gas ions and molecular nitrogen, measuring nitrogen ion kinetic energy distributions
First collision Monte Carlo method for calculating aerodynamic drag on hard sphere and Maxwell molecular models in near-free molecular flow
Diatomic Br molecular vibration-rotation coupling effects on energy transfer during Br-Ar collisions, determining probability distributions
Time-of-flight measurements for relationship between velocity, mass and temperature in molecular gas motion and electron-atom collision kinematics
CO observations of nearby galaxies with nuclear active star forming regions (and starburst galaxies) with angular resolutions around 7 seconds revealed that molecular bars with a length of a few kiloparsecs have been formed in the central regions of the galaxies. The molecular bar is interpreted as part of shock waves induced by an oval or barred potential field. By shock dissipation or dissipative cloud-cloud collisions, the molecular gas gains an infall motion and the nuclear star formation activity is fueled. But the distribution and kinematics of the molecular gas in the nuclear regions, which are sites of active star formation, remain unknown. Higher angular resolutions are needed to investigate the gas in the nuclear regions. Researchers made aperture synthesis observations of the nuclear region of the late-type spiral galaxies NGC 6946 and IC 342 with resolutions of 7.6 seconds x 4.2 seconds (P.A. = 147 deg) and 2.4 seconds x 2.3 seconds (P.A. = 149 deg), respectively. The distances to NGC 6496 and IC 342 are assumed to be 5.5 Mpc and 3.9 Mpc, respectively. Researchers have found 100-300 pc nuclear gas disk and ring inside a few kpc molecular gas bars. Researchers present the results of the observations and propose a possible mechanism of active star formation in the nuclear region.
Numerical integration calculation of collision integrals for exponential attractive potential of gases
Numerical values describing molecular rainbow scattering in Airy approximation for 12-6 potential
Transition probabilities of nitrogen-nitrogen collision obtained with time-dependent wave functions of forced harmonic oscillator and by numerical methods
Collisions in inner region of cometary head, structure of emission bands and formation of free radicals
Vibrational energy transfer in high energy collisions of diatomic nitrogen, evaluating transition probabilities for forced harmonic oscillator
Collision-induced transitions can significantly affect molecular vibrational-rotational populations and energy transfer in atmospheres and gaseous systems. This, in turn. can strongly influence convective heat transfer through dissociation and recombination of diatomics. and radiative heat transfer due to strong vibrational coupling. It is necessary to know state-to-state rates to predict engine performance and aerothermodynamic behavior of hypersonic flows, to analyze diagnostic radiative data obtained from experimental test facilities, and to design heat shields and other thermal protective systems. Furthermore, transfer rates between vibrational and translational modes can strongly influence energy flow in various 'disturbed' environments, particularly where the vibrational and translational temperatures are not equilibrated.
The role of orbit crowding and cloud-cloud collisions in the formation of GMCs and their organization in global spiral structure is investigated. Both N-body simulations of the cloud system and a detailed analysis of individual particle orbits are used to develop a conceptual understanding of how individual clouds participate in the collective density response. Detailed comparisons are made between a representative cloud-particle simulation in which the cloud particles collide inelastically with one another and give birth to and subsequently interact with young star associations and stripped down simulations in which the cloud particles are allowed to follow ballistic orbits in the absence of cloud-cloud collisions or any star formation processes. Orbit crowding is then related to the behavior of individual particle trajectories in the galactic potential field. The conceptual picture of how GMCs are formed in the clumpy ISMs of spiral galaxies is formulated, and the results are compared in detail with those published by other authors.
IQSY rocket measurements in C, D, and E layers of ionosphere - electron density, collision frequency, molecular oxygen density, and ionization
Monte Carlo method solution of heat transfer in rarefied gas between infinite flat plates