Stark-induced temporal intensity variations in spectral lines.
Stark splitting effect on fine structure level probabilities for hydrogen lines, taking account of spontaneous transition probabilities and Lamb shift
FINE STRUCTURE↗
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Phased models for evaluating the performability of computing systems
A phase-by-phase modelling technique is introduced to evaluate a fault tolerant system's ability to execute different sets of computational tasks during different phases of the control process. Intraphase processes are allowed to differ from phase to phase. The probabilities of interphase state transitions are specified by interphase transition matrices. Based on constraints imposed on the intraphase and interphase transition probabilities, various iterative solution methods are developed for calculating system performability.
Wu, L. T.↗
Vacuum ultraviolet monochromator calibration using measured atomic branching ratios
It is noted that there now exists a compendium of experimentally measured transition probability ratios for ionized transitions of oxygen, nitrogen, and sulfur, which can be used for calibration in the VUV spectral region. The emissions proposed for use in this context span the 485-1124 A wavelength interval, and can be easily excited using low pressure discharge lamps of conventional design and dispersed using a monochromator of moderate resolution.
Morrison, M. D.↗
S II and S III branching ratios in the 600- to 1200-A interval
Branching ratios are presented of singly and doubly ionized sulfur EUV emissions. They are determined by measuring the relative photon intensities of each of the branching components. For several transitions in S II for which mean lifetimes have been measured with fast-beam spectroscopy, the data presented here are used to determine transition probabilities. The S II transitions originate from the 2P, 4s-prime 2D, and 4s 2P terms and terminate on the metastable states of the ion. The S III transitions originate from the 3d 3D0, 4s 3P0, 3p3 3S0, 4s 1P0, and 3s3p3 1P0 terms and terminate on the metastable and ground ionic states. The results for S III include branching ratios involving intercombination transitions that affect ongoing modeling of the energy budget of the Io plasma torus.
Morrison, M. D.↗
Dipole Transition Integrals for Non-metal Resonance Transitions
Dipole integrals for nonmetal resonance transition probabilities
INTEGRAL EQUATION↗
Seasonal Variations of Stratospheric Age Spectra in GEOSCCM
There are many pathways for an air parcel to travel from the troposphere to the stratosphere, each of which takes different time. The distribution of all the possible transient times, i.e. the stratospheric age spectrum, contains important information on transport characteristics. However, it is computationally very expensive to compute seasonally varying age spectra, and previous studies have focused mainly on the annual mean properties of the age spectra. To date our knowledge of the seasonality of the stratospheric age spectra is very limited. In this study we investigate the seasonal variations of the stratospheric age spectra in the Goddard Earth Observing System Chemistry Climate Model (GEOSCCM). We introduce a method to significantly reduce the computational cost for calculating seasonally dependent age spectra. Our simulations show that stratospheric age spectra in GEOSCCM have strong seasonal cycles and the seasonal cycles change with latitude and height. In the lower stratosphere extratropics, the average transit times and the most probable transit times in the winter/early spring spectra are more than twice as old as those in the summer/early fall spectra. But the seasonal cycle in the subtropical lower stratosphere is nearly out of phase with that in the extratropics. In the middle and upper stratosphere, significant seasonal variations occur in the sUbtropics. The spectral shapes also show dramatic seasonal change, especially at high latitudes. These seasonal variations reflect the seasonal evolution of the slow Brewer-Dobson circulation (with timescale of years) and the fast isentropic mixing (with timescale of days to months).
Li, Feng↗
On the spectra of coronal ions connected with sp3-configurations <o spektrakh koronal'nykh ionov svyazannykh s konfiguratsiami sp3<
Ultraviolet spectra and transition probabilities for coronal ions
ULTRAVIOLET SPECTRUM↗
Vibrational energy transfer in high-energy collisions.
Vibrational energy transfer in high energy collisions of diatomic nitrogen, evaluating transition probabilities for forced harmonic oscillator
FORCED OSCILLATION↗
Plasma spectroscopy
Transition probabilities, excitation cross sections, and neon glow studies for plasmas
TRANSITION PROBABILITY↗
Spectrum and relative intensities of interstellar oh lines.
Frequencies, relative intensities and transition probabilities of interstellar OH microwave spectral lines
HYDROXYL↗
On the spectrum and relative intensities of interstellar oh lines
Line frequencies, relative intensities, and transition probabilities of OH lines in interstellar microwave spectrum
LINE SPECTRUM↗
The sudden approximation applied to molecular problems. I - Non-reactive collisions
Sudden approximation for calculating transition probabilities for energy transfer during collisions between molecules and atoms
ATOMIC COLLISION↗
Theory of atomic transitions
Transition probabilities of atomic collisions, elastic scattering of electrons, and excitation functions
ELECTRON COLLISION↗
Atomic spectroscopy with the shock tube
Spectroscopy of light atoms and ions and transition probability determinations using gas-driven shock tube
GAS SPECTROSCOPY↗
Sudden approximation applied to rotational excitation of molecules by atoms. ii- scat- tering of polar diatomics
Sudden approximation applied to computation of rotational transition probability and inelastic total cross sections for scattering of polar and nonpolar diatomic molecules by atoms
SCATTERING↗
Sudden approximation applied to rotational excitation of molecules by atoms. II - Scattering of polar diatomics.
Sudden approximation applied to rotational transition probabilities and inelastic total cross sections for scattering of homonuclear diatomic molecules by atoms
SCATTERING CROSS SECTION↗
Direct measurements of predissociation probabilities in CH and CD molecules.
CH and CD molecule predissociation probabilities measured directly and compared with radiative transition probability
Hesser, J. E.↗
Unidentified lines in molecular clouds and a search for C-14 in IRC +10216
Two spectral features have been detected toward the Kleinmann-Low infrared nebula in Orion that agree in frequency with the 7(25)-7(16) and 7(35)-7(26) rotational transitions of the ring-structured molecule ethylene oxide (CH2)2O. A feature agreeing in frequency with the 8(24)-8(45) transition probably also was detected; however, seven other transitions in (CH2)2O were not. Additional unidentified lines were detected in Ori A and Sgr B2. Searches for H(C-14)N and (C-14)O in the luminous carbon star IRC +10216 were unsuccessful. However, an unidentified line was found in IRC +10216 that was not detected in the KL nebula.
Kuiper, E. N. R.↗