Interpretation of high-resolution spectra of Venus. I
High resolution Venus spectra, obtaining band spectra growth curve of C13O16O18 isotope of carbon dioxide, comparing data reduction methods
Young, L. G.↗
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Analysis of continuous pulse height spectra
Continuous differential energy pulse height spectra reduction to photon upper atmospheric spectra
Trombka, J. I.↗
Cosmic ray proton and helium spectra above 50 GeV
Differential energy spectra of cosmic ray protons and helium nuclei were measured by an ionization spectrometer flown at balloon altitudes. The energy range extended from 50 GeV to above 1000 GeV. The observed differential intensities can be represented with power law spectra with a slope of -2.75 + or - 0.03 for protons and of -2.77 + or - 0.55 for helium nuclei. The proton to helium ratio is equal to 26 + or - 3 at 40 GeV/nuc and is constant within errors up to 400 GeV/nuc.
Ryan, M. J.↗
The spectra of ten galactic X-ray sources in the southern sky
Data on ten galactic X-ray sources were obtained during a rocket flight from Brazil in June 1969. Detailed spectra of these sources have been compared with bremsstrahlung, black body, and power law models, each including interstellar absorption. Six of the sources were fitted well by one or more of these models. In only one case were the data sufficient to distinguish the best model. Three of the sources were not fitted by any of the models, which suggests that more complex emission mechanisms are applicable. A comparison of our results with those of previous investigations provides evidence that five of the sources vary in intensity by a factor of 2 or more, and that three have variable spectra. New or substantially improved positions have been derived for four of the sources observed.
Cruddace, R.↗
Spectra-spectroheliograph observations.
This paper describes a photographic technique for recording solar spectra. The technique, which we call spectra-spectroheliography, requires the same amount of observing time as conventional spectroheliography but yields much more information. Data reduction techniques have been developed to use this information for the construction of spectroheliograms and other contour maps. Parameters investigated by this method include the vector magnetic field, line-of-sight velocity, continuum intensity, and line strength. Results indicate (1) good correlation between bright regions in spectroheliograms and small vertical magnetic fields; (2) poorer correlation between larger magnetic fields and bright regions; (3) a feature in the continuum resembling a pore but having no vertical magnetic field; and (4) a gradient in the vertical magnetic field of 12kG/arc sec.
Title, A. M.↗
Photoionization and the emission-line spectra of quasi-stellar objects.
Detailed photoionization calculations are used to examine the information conveyed by relative emission-line intensities in QSO spectra. It is found that the elemental abundances cannot be estimated with any assurance; but if ?conventional' values are assumed, then certain restrictions may be placed on the ionizing spectra and gas densities. In particular, the ratio between radiation density and gas density is determined. Narrow filaments or sheets of ionized gas seem to be indicated; these may be compressed regions behind shock fronts.
Davidson, K.↗
Carbon-like spectra of Sc XVI, Ti XVII, and V XVIII in the range 16-22 A.
The spectra reported are important for the analysis of the spectra of CaXV and FeXXI. The extreme UV solar spectrum should contain some lines of these two ions. The spectroscopic source consisted of a low-inductance vacuum spark with electrodes made of the elements under investigation. Altogether 44 new lines in the region from 16 to 22 A were classified. Some previously unidentified lines of ClXII and ArXIII were also classified. The extrapolation of the ground-configuration energy levels is discussed.
Goldsmith, S.↗
Optical spectra of quasi-stellar objects.
Account of the emission lines of QSOs, with discussion of the absorption-line spectra and an account of the optical continua. Attention is given to both radio-emitting and radio-quiet QSOs, since there appears to be no distinction in their optical spectra, and objects at all observed redshifts are included.
Burbidge, E. M.↗
Cosmic-ray proton and helium spectra above 50 GeV.
Differential energy spectra of cosmic-ray protons and He nuclei have been measured for the first time by an ionization spectrometer flown at balloon altitudes. The energy range extended from 50 to more than 1000 GeV. The observed differential intensities can be represented with power-law spectra with a slope of -2.75 (plus or minus 0.03) for protons and of -2.77 (plus or minus 0.05) for He nuclei. The proton-to-He ratio is 26 (plus or minus 3) at 40 GeV/nucleon and is constant within errors up to 400 GeV/nucleon.
Ryan, M. J.↗
Cosmic-ray source and local interstellar spectra deduced from the isotopes of hydrogen and helium.
A self-consistent model for cosmic-ray hydrogen and helium propagation from the sources in the Galaxy to the orbit of earth is obtained, taking into account experimental information now available on the isotopes H-1, H-2, He-3, and He-4. The only adjustable parameters include the shape of the energy spectra of H-1 and He-4 at the time of source injection, the distribution of particle path lengths in interstellar space, and the solar modulation parameters. It is found that the allowed form of the source differential spectra of the H-1 and He-4 nuclei is dominated by a power law in total energy.
Comstock, G. M.↗
Polarized absorption spectra of single crystals of lunar pyroxenes and olivines.
Measurements have been made of the polarized absorption spectra (360-2200 nm) of compositionally zoned pyroxene minerals in rocks 10045, 10047 and 10058 and olivines in rocks 10020 and 10022. The Apollo 11 pyroxenes with relatively high Ti/Fe ratios were chosen initially to investigate the presence of crystal field spectra of Fe(2+) and Ti(3+) ions in the minerals. Broad intense bands at about 1000 and 2100 nm arise from spin-allowed, polarization-dependent transitions in Fe(2+) ions in pyroxenes. Several weak sharp peaks occur in the visible region. Peaks at 402, 425, 505, 550, and 585 nm represent spin-forbidden transitions in Fe(2+) ions, while broader bands at 460-470 nm and 650-660 nm are attributed to Ti(3+) ions. Charge transfer bands, which in terrestrial pyroxenes often extend into the visible region, are displaced to shorter wavelengths in lunar pyroxenes. This feature correlates with the absence of Ti(3+) ions in these minerals.
Burns, R. G.↗
The lithium-like spectra of K XVII through Mn XXIII in the extreme-ultraviolet region.
Identifications and classifications of spectral lines in the lithium-like spectra of the elements K through Mn is presented for the first time. The extrapolation procedures used to calculate these spectra are presented in detail. The excellent agreement between the predicted and measured lines establish the long-range extrapolation.
Goldsmith, S.↗
The Nimbus 4 infrared spectroscopy experiment. I - Calibrated thermal emission spectra.
Measurement of the infrared spectrum of the earth and atmosphere between 400 and 1600/cm. In an effort to obtain spectra with high absolute accuracy, it was necessary to incorporate many factors into the calibration, including small departures from unity in the emissivity of the on-board calibration source, imbalance between cold and warm calibration ports, and effects due to orbital variations in instrument temperature. The inclusion of such higher order corrections, along with careful data screening processes, has ensured a high quality data set that can be used in a variety of geophysical and meteorological investigations. Representative samples of data are presented that illustrate the behavior of the thermal emission spectra under a variety of conditions encountered in a typical orbit, including extremes in temperature, surface reststrahlung (or residual ray) effects, and various types of cloud conditions.
Hanel, R. A.↗
Vibrational spectra and structure of azomethane and azomethane-d6.
The infrared and Raman spectra of azomethane and azomethane-d(6) were examined in detail. Vibrational data provided definitive verification of a trans-structure with C(2h) symmetry. A vibrational assignment is proposed for the 24 fundamental modes based upon the observed contours, isotopic shift ratios, and group frequency correlations. Spectra of the polycrystalline samples indicate that there are at least four molecules per unit cell, since a number of the bands were observed to be split into doublets. The crystal also appeared to have a center of symmetry, since mutual exclusion was clearly operative.
Durig, J. R.↗
The spectra of ten galactic X-ray sources in the southern sky.
Data on 10 galactic X-ray sources located between 320 and 20 deg galactic longitude were obtained during a rocket flight from Brazil in June 1969. Detailed spectra of these sources have been compared with bremsstrahlung, blackbody, and power-law models, each including interstellar absorption. Six of the sources were fitted well by one or more of these models. In only one case were the data sufficient to distinguish the best model. Three of the sources were not fitted by any of the models, which suggests that more complex emission mechanisms are applicable. A comparison of our results with those of previous investigations provides evidence that five of the sources vary in intensity by a factor of two or more, and that three have variable spectra.
Cruddace, R.↗
Nimbus 4 IRIS spectra in the 750-1250/cm atmospheric window region
Several Nimbus 4 IRIS spectra are presented for the 700-1300/cm region as examples of free atmosphere spectra to illustrate problems encountered in interpreting window measurements. Several atmospheric windows near 936 and 960/cm appear significantly more transparent than the 899/cm window presently used in operational remote sensing systems.
Kunde, V. G.↗
A satellite measurement of cosmic-ray abundances and spectra in the charge range 2 less than or equal to 7 less than or equal to 10
The composition of the nuclear component of the cosmic radiation was studied to yield information concerning the source, propagation, and confinement of cosmic rays within the galaxy. The first comprehensive satellite measurement is presented of cosmic-ray composition and spectra in the charge range 2 equal to or less than Z equal to or less than 10 using the geomagnetic field as a rigidity analyzer through the entire range of vertical cutoffs. The results indicate that the spectra of all the elements in the observed range are similar, and thus that various ratios of elemental abundances are nearly independent of rigidity over the range 2 equal to or less than P equal to or less than 15 GV. Calculations of the propagation of cosmic rays through the interstellar and interplanetary media predict that there should be a variation with rigidity of ratios of various elements, because of the charge-dependent effects of ionization of the interstellar gas by the cosmic rays. The absence of this variation can be explained by assuming a rigidity-dependent confinement of the cosmic rays in the galaxy.
Brown, J. W.↗
Energy spectra in relativistic electron precipitation events.
Two events in August 1967, categorized as relativistic electron precipitation (REP) events by their effect on VHF transmissions propagated via the forward-scatter mode, have been examined with regard to the energy spectra of trapped and precipitated electrons. These two substorm-associated events August 11 and August 25 differ with respect to the relativistic, trapped electron population at synchronous altitude; in the August 25 event there was a nonadiabatic enhancement of relativistic (greater than 400 keV) electrons, while in the August 11 event no relativistic electrons were produced. In both events electron spectra deduced from bremsstrahlung measurements (made on a field line close to that of the satellite) had approximately the same e-folding energies as the trapped electron enhancements. However, the spectrum of electrons in the August 25 event was significantly harder than the spectrum in the event of August 11.
Rosenberg, T. J.↗