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Radial velocity errors in high dispersion astronomical spectrographs in terms of variable spectral shifts along plate produced by mirror surface irregularities
Short-length annular combustor for turbojet engines eliminates change of exit temperature profile. Individual scoops of full annular height control air distribution so that shifts in the radial velocity profile of air entering the combustor will not affect combustion process or alter exit temperature profile.
Cylindrical axial plasma flow fields velocity radial dependence measurement by double-wedge spectroscopy using Abel unfolding of Doppler shifts
Water vapor emission detection from IR stars, discussing radial velocities of microwave lines
Galaxy cluster expansion theory, noting dispersion in radial velocities of members
Radio observation for radial velocities in center region of Perseus cluster of galaxies
The nebular (O II) lambda 3726 and (O III) lambda 5007 radial velocity measures of Wilson, et al (1959) are presented in contour map form. The space motions of theta 1 and theta 2 Orionis and the nebular measures are discussed.
Analysis of a spectrum of zeta Ori extending from 922 to 1453 A with approximately 0.8 A resolution recorded at rocket altitudes. All lines used in existing models of stellar atmospheres appear in the recorded spectrum with the exception of those masked by telluric N2 or strong P Cygni-type profiles and by an O V line at 1371.29 A. Fifteen multiplets of subordinate lines have been reliably identified, indicating an approximate range of excitation from 0 to 50 eV. Transitions in C III (1176 A), N III (991 A), N V (1239, 1243 A), O VI (1032, 1038 A), Si IV (1394, 1403 A), S IV (1063, 1074 A), and S VI (933, 944 A) have been observed as P Cygni-type profiles presumably arising in a circumstellar envelope. The degree of ionization, transitions present, and mean radial velocities are all consistent with viewing the envelope as a hot (about 100,000 K), rarefied plasma in which collisional ionization is important. Interstellar lines in C I (1277, 1280 A), C II (1036, 1334 A), N I (1134-1135 A), N I (1200-1201 A), N II (1084-1086 A), O I (1302, 1305 A), Si II (1190, 1193 A), Si II (1260 A), and Si II (1304 A) have been definitely identified. Other transitions in Ar II, S I, C I, and Fe II are tentatively identified. The equivalent width of the L alpha line is found to be 10.4 plus or minus 1.6 A, corresponding to a columnar density of 2.0 plus or minus 0.7 x 10 to the 20th per cu cm.
The idealized basic structure of the interplanetary magnetic field is the familiar spiral wound on a cone whose axis is the solar rotation axis. Variations in the radial velocity of the solar wind produce large scale variations in pitch; slight distortions are also produced by the nonradial component of the solar wind velocity. The high velocity streams in the solar wind seem to be more significant than magnetic polarity alternation in the sector structure of the interplanetary medium. Superposed on the ideal spiral are a variety of smaller structures. Outwardly propagating nonsinusoidal Alfven waves with scale lengths of .1 to 10 million kilometers are common. When sharp crested, they are recognized as rotational discontinuities. Other, less easily identified, waves are present part of the time. Tangential discontinuities and other convected structures have been identified, as have interplanetary shock waves.
Analysis of radial velocities in the coma cluster (many of them new) in conjunction with previous data on the density distribution. The cluster extends more than 200 min in radius, with bright and faint galaxies distributed in nearly the same way. Some spirals are members. Several different determinations of M/L give values around 250. The cluster is stabilized by a 'missing mass' some seven times the mass of the galaxies, which must be distributed in the same way as the galaxies.
Shape and inner flow of a tridimensional spark are studied. The spark is created by focusing a laser beam in a gas. A second order fully non-linear equation is derived for the radial velocity on the axis of symmetry in the neighborhood of the origin. Solutions to that equation display the existence of a forbidden region near the focus, thus indicating the limits of applicability of a small perturbation solution.
Spectrometric scans of faint optical emissions from interstellar gas are reported. Systematic variations along the galactic plane in both the intensity and radial velocity of the galactic H alpha suggest that the diffuse emission is strongly associated with three nearby galactic spiral arms.
A visualization study of the flow through a three ft dia model of a four bladed inducer, which is operated in air at a flow coefficient of 0.065, is reported in this paper. The flow near the blade surfaces, inside the rotating passages, downstream and upstream of the inducer is visualized by means of smoke, tufts, ammonia filament, and lampblack techniques. Flow is found to be highly three dimensional, with appreciable radial velocity throughout the entire passage. The secondary flows observed near the hub and annulus walls agree with qualitative predictions obtained from the inviscid secondary flow theory.
An approximate solution for the laminar flow of an incompressible viscous fluid in the entrance region of a converging channel is obtained. The radial velocity distribution at the entrance of the channel is taken to be a symmetric but otherwise arbitrary function of the angular position. Expressions for the velocity components and pressure are given. The case of the uniformly distributed entrance velocity is considered as an example.
Shakhbazian (1957) reported a cluster of red objects which he interpreted to be a cluster of stars in Ursa Major at a distance of 130 kpc. Spectra obtained with an image-tube scanner for 5 members of this cluster show that they are all galaxies with a redshift corresponding to a radial velocity 29.700 km/sec. The remaining 12 members of the group appear to be diffuse, and are probably also galaxies.
Investigation of the long-period V/R variation in some Be stars studied by McLaughlin (1966) and others, based on the assumption that the variation is caused by the apsidal motion of an elliptical ring in which the emitting atoms revolve around the star according to Kepler's laws of motion. The results indicate that the behavior of the V/R variation depends upon both the eccentricity and the lateral extent of the gaseous ring. However, if the ring is narrower than a certain limit, the dependence on the width is negligible. In such a case, the eccentricity of the ring can be determined by the observed amplitude of the V/R variation. Based on this model, the radial-velocity curves of both emission edges and central absorption are derived. It is found that they all have the same amplitude, which also depends on the eccentricity, and that all are changing in phase with the V/R variation.
The stress wave riveter deforms the rivet material by a high amplitude stress wave. Thus, the entire rivet is set in motion radially. The rivet expands rapidly and impacts the hole surface before the rivet tail begins to form. Unlike the oversqueezed rivets, therefore, it sets up uniform interference without distortion in the skins. Furthermore, the radial velocity is so high (over 200 in./sec) that upon impact with the hole surface it deforms the surface plastically. This is especially effective in aluminum skins. Thus the SWR combines the advantages of plastically deforming the hole and the economic advantage of a relatively nonprecision hole and inexpensive rivets like those used in oversqueezing. The additional advantage SWR offers is that it is a portable tool.
An overlooked systematic error exists in the apparent radial velocities of solar lines reflected from regions of Venus near the terminator, owing to a combination of the finite angular size of the Sun and its large (2 km/sec) equatorial velocity of rotation. This error produces an apparent, but fictitious, retrograde component of planetary rotation, typically on the order of 40 meters/sec. Spectroscopic, photometric, and radiometric evidence against a 4-day atmospheric rotation is also reviewed. The bulk of the somewhat contradictory evidence seems to favor slow motions, on the order of 5 m/sec, in the atmosphere of Venus; the 4-day rotation may be due to a traveling wave-like disturbance, not bulk motions, driven by the UV albedo differences.