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Spectra of Cs III, Ba IV, and La V were photographed in a low-voltage sliding spark on a 10.7 m normal-incidence vacuum spectrograph. These ions are isoelectronic with neutral iodine and display a halogen-like energy level structure. Detailed isoelectronic comparisons, level transition diagrams, and tabular data on the transitions of the ions and percentage compositions of Cs III configurations are presented.
The high resolution rotational band profiles were fitted with theoretical band profiles which are derived using a Boltzmann temperature of 70 K. A very rapid variation with heliocentric distance for the CS brightness was found. The implications of these results for models of the coma along with the origin of the CS species are discussed.
Results from ultraviolet spectrographic observations of Comet West (1975n) in the 1620-3960 A wavelength range are presented. Objective grating imagery of the comet reveals for the first time emission from sulfur atoms and CS molecules as well as previously observed lines or bands in carbon atoms and CO(+), CO2(+) and OH molecules. Some evidence exists for emission in the C2 Mulliken bands and in the CO Cameron bands. On the basis of the observations, production rates of C (ground state), C(1D), S, and CS are inferred to be 3.8 x 10 to the 29th per sec, 4.4 x 10 to the 29th per sec, 1.7 x 10 to the 28th per sec, and greater than approximately 3.1 x 10 to the 27th per sec, respectively.
The high resolution spectra of comets Giacobini-Zinner and Halley were measured in the region of the CS emission. Both spectra have essentially the same shape, but the Halley spectrum has a better signal to noise ratio. The rotational distribution of the radical in these comets was derived by using an inversion program and spectral simulation. Both procedures suggest that the rotational distribution is dominated by CS radical with J" is less than or = 5. Despite this it appears that another distribution with higher J''' is needed to explain the shape of the rotational distribution. It is suggested that this second distribution is due to a balance between collisions and radiation in the inner coma.
New vibrational bands of CS have been identified in several comets. The relative intensities of these bands are in agreement with a simple model, based upon most of the CS radicals being in the lowest vibrational level. The present observational accuracy is not sufficient to decide between this simple model and an earlier radiative equilibrium model. The observed intensity ratios appear to be similar in different comets, which means that they cannot depend strongly upon the total gas production rates.
The high resolution spectrum of comet P/Halley has been measured in the region of the CS emission. CS in comet Halley is produced by photodissociation of CS2 and subsequently reexcited by broad band solar radiation. An inversion procedure is introduced to extract the rotational population distribution from the dispersed fluorescence spectrum. Intensity anomalies in the wavelength region corresponding to P and Q branch emission are considered.
NASA’s Multi Purpose Transportation System (MPTS) is designed to transport the Space Launch System vehicle segments by waterway and roadway. It is tasked with transporting the vehicle from where it is manufactured to its intermediate test location and final launch destination. Its design incorporates mechanisms that release degrees of freedom to prevent excessive loading during transit and ensure a successful delivery of the vehicle to its intended destination. In addition to the CS (Core Stage) flight article, the system will also move three structural test articles and a simulated CS Pathfinder (weight, center of gravity, outer mold line dimensions, and overall length) over road terrain on four NASA centers and on the Pegasus barge. The MPTS independently supports the article at both ends while communicating as a combined unit through automated monitoring of its released degree of freedom and corrective responses. This allows the system to constrain its payload in a statically determinate manner while traversing across highly variable terrain. Multi-body simulation of the transportation route is useful to predict free-body motion within the specified travel ranges. The MPTS has completed its design and analysis developmental cycles. This unpublished paper will describe the design challenges encountered in developing this system of large scale structure which incorporates complex mechanisms. The unique techniques and methodologies developed for analytical assessment of the hardware will be also be discussed. Key results from analytical evaluations as well as ongoing performance testing will be presented.
NASA's Multi-Purpose Transportation System (MPTS) is designed to transport the Space Launch System (SLS) vehicle segments by waterway and roadway. It is tasked with transporting the vehicle from where it is manufactured to its intermediate test location and final launch destination. Its design incorporates mechanisms that release degrees of freedom to prevent excessive loading during transit and ensure a successful delivery of the vehicle to its intended destination. In addition to the Core Stage (CS) flight article, the system will also move three Structural Test Articles (STAs), the Dynamic Demonstration Unit (DDU), and a simulated CS Pathfinder (weight, center of gravity, outer mold line dimensions, and overall length) over road terrain at four NASA centers and on the Pegasus barge. The MPTS independently supports the article at both ends while operating as a combined unit through automated monitoring of its released degree of freedom and corrective responses. This allows the system to constrain its payload in a statically determinate manner while traversing highly variable terrain. Multi-body simulation of the transportation route is useful to predict free-body motion within its range of mobility. The MPTS has completed its design and analysis developmental cycles. This paper describes the design challenges encountered in developing this system of large-scale structure, which incorporates complex mechanisms. The unique techniques and methodologies developed for analytical assessment of the hardware are also discussed.
We report Doppler-only (cw) radar observations of 1991 CS obtained at Goldstone at a transmitter frequency of 8510 MHz (3.5 cm) on 1996 August 26, 27, 28, and 29.
Simple model atom selection for electron density calculation in low temperature nonequilibrium Cs plasmas
Electron beam retarding potential method to measure work function changes resulting from Cs, oxygen and hydrogen adsorption on /110/ Ta single crystal
Radiative lifetimes of transitions to ground state for CS, SO and diatomic sulfur, showing relationship to absolute transition probabilities in terms of physiochemical applications
Chemical analysis for Li, Na, K, Rb, Cs, Ca, Sr and Ba in achondrites and Apollo 11 lunar rocks, breccia and soil samples
Na-Cs unpolarized and spin exchange differential scattering cross sections calculation by phenomenological and difference potential methods
The reported observations were made with an 11-m radio telescope. The CO map considered has a peak near the position of the infrared continuum source. There is little correlation between the CO contours and any optical structure. The CO contours show a pronounced north-south orientation. CS was observed as a representative example of a stable molecule with a higher dipole moment than CO. Questions regarding the structure of Orion A are discussed, giving attention to various models.
Rates for excitation of CO, CS, OCS, and HC3N by collisions with He atoms and H2 molecules are presented. These have been obtained from extensive theoretical calculations using methods of known reliability. In general, rates necessary for modeling interstellar molecular clouds with kinetic temperatures to 100 K have been included. Methods for fitting these rates in more compact form are discussed.
The purpose of the Japanese CS-2 satellite is to provide national communications and industrial communications, such as special emergency and remote communications, and to contribute to the development of technology pertaining to communications satellites. Description and operating parameters of the following satellite components are presented: structure, communications system, telemetry/command system, electric power system, attitude and antenna control system, secondary propulsion system, apogee motor, framework, and heat control system.
The problem of the quantum treatment of nonreactive collisions of two simple molecules or of an atom and a molecule is considered mathematically. Kinematical structure theorems analogous to the Wigner-Eckart theorem for scalar operators are derived for the transition operator (T-operator) of a two-molecule system, where, in addition to the usual conservation laws, certain additional conservation laws are presumed satisfied in a collision. The additional conservation laws were examined in order to develop a testable approximation scheme (CS method) for the specification of the kinematics of a system of two rigid diatomic molecules. The rand p-helicity basis states for a two-rigid rotor system are defined and unitary transformations established between these and conventional bases. It is found that only questionable criteria exist for testing the on-the-energy-shell matrix of a T(energy) operator for the presence of properties of two of the additional conservation laws.