Furnace Spectra Research Articles

Transition rates for ZrO from a laboratory absorption spectrum

view Abstract Citations (10) References (19) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Transition Rates for ZrO from a Laboratory Absorption Spectrum Littleton, J. E. ; Davis, Sumner P. ; Song, Mei Abstract A new analysis of the B-X(0-0), beta-3(0-0), and gamma(0-0) bands in the B 1Pi - X 1Sigma(+), c 3Pi2-A 3Delta3, and b 3Phi-a 3Delta systems, respectively, in the laboratory spectrum of ZrO is reported. A Fourier transform spectrometer is used to obtain an absorption spectrum produced by ZrO in a King furnace at 2730 K. The electronic dipole moments obtained in the present analysis are employed to compute synthetic spectra for the B-X(0-0) and gamma-1(0-0) bands. The synthetic spectra for both emission and absorption match the furnace spectra well, verifying the present absorption spectrum results. Publication: The Astrophysical Journal Pub Date: February 1993 DOI: 10.1086/172290 Bibcode: 1993ApJ...404..412L Keywords: Absorption Spectra; Electron Transitions; Zirconium Oxides; Dipole Moments; Emission Spectra; Fourier Transformation; Spectral Bands; Spectrometers; Spectrum Analysis; Atomic and Molecular Physics; MOLECULAR PROCESSES; TECHNIQUES: SPECTROSCOPIC full text sources ADS |

A high dispersion study of some new absorption bands of CaH and CaD in the ultra-violet region

King furnace spectra of CaH and CaD at temperatures greater than 1200 °c have been obtained in absorption. Five new bands of CaH at 2815 Angstrom, 2752 Angstrom, 2609 Angstrom, 2580 Angstrom, 2535 Angstrom and two new bands of CaD at 2711 Angstrom and 2646 Angstrom have been measured and analysed. Of these, the two CaD bands and the first three CaH bands have been shown to be extensions of some of the systems already reported. The CaH bands at 2580 Angstrom and 2535 Angstrom, however, have been analysed as the (0, 0) bands of two different systems, which may be called H 2Σ -> X 2Σ and I 2Σ -> X 2Σ transitions, respectively. Rotational constants have also been calculated where necessary.

The optical spectrum of plutonium and its hyperfine structure

Synopsis Plutonium is excited in a hollow cathode discharge and the emitted light in the wavelength region 2900–6490 A is observed by means of prism spectrographs. The wavelengths of nearly 2000 Pu-lines are measured against argon reference lines with an accuracy corresponding to an approximately constant mean wave number error of ± 0.2 K in the region above 3705 A and of ± 1.0 K in the shorter wavelength region. By comparing the intensities with those observed in spark discharges by other authors, a preliminary separation of the stronger Pu I- and Pu II-lines is possible. About 85% of the lines observed in the hollow cathode belong to Pu I. This is confirmed by a recent paper on the furnace spectrum. A list is given of the 714 strongest observed lines, with the assignment to Pu I or Pu II. The 75 strongest Pu-lines between 4020 and 6200 A are examined by means of etalons, and a hyperfine structure doubling is found in 30 of them, with separations of 34 to 181 mK. It is proved that this doubling is due to a 239 Pu nuclear spin value I = ½. Intensity measurements in some selected doublets show that high J-values are involved in the observed transitions. Possible consequences with regard to the electronic structure of the free atom are discussed. The nuclear spin value of 239 Pu is considered in the light of the nuclear shell model.

Relative Transition Probabilities of the Swan Bands of Carbon.

view Abstract Citations (26) References Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Relative Transition Probabilities of the Swan Bands of Carbon. King, Robert B. Abstract The relative transition probabilities of the vibrational bands in the Swan system (~ll~-~ll~) of the car- bon molecule C2 have been derived from relative intensities of the band heads appearing in electric-furnace emission spectra under conditions of thermodynamic equilibrium. The method and possible sources of error are discussed. The results from furnace spectra are compared with those from theoretical and experimental work of other investigators Publication: The Astrophysical Journal Pub Date: November 1948 DOI: 10.1086/145078 Bibcode: 1948ApJ...108..429K full text sources ADS | Related Materials (1) Reprint: 1948CMWCI.752....1K

Temperature Classification of Europium Lines.

view Abstract Citations (7) References Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Temperature Classification of Europium Lines. King, Arthur S. Abstract The paper gives wave-length measures and temperature classifications for 3950 europium lines from X 2100 to X 10165. Of these, slightly less than 2200 belong to neu- tral europium. A very large intensity range is found for both neutral and singly ionized lines. Many of the former are relatively stronger in the furnace than in the arc. The absorption furnace spectrum was used to obtain low-level lines in the ultraviolet to X 2659. Lines of Eu ii, selected by comparison of arc and spark spectra, range from low- level furnace lines to those much enhanced in the spark. An ultraviolet spark spectrum, which is absent from the arc, probably belongs to Eu m. In addition to arc and furnace intensities, the degree of widening, due to hyperfine structure, of a large proportion of the lines is indicated in Table 2. Close agreement of lines in the sunspot spectrum with the ultimate lines of Eu i indicates the presence of neutral europium in the solar atmosphere. Additional identi- fications of Eu II lines in the sun have been made. Approximately three-fourths of the lines ascribed by Eder to a suggested unknown substance "eurosamariuna" have been identified as belonging to known rare earths, nearly haff being lines of europium. Seventeen bands of EuC13 appearing in the furnace spectrum from X 5695 to X 745o have their limiting wave lengths given and their distinctive features described Publication: The Astrophysical Journal Pub Date: April 1939 DOI: 10.1086/144061 Bibcode: 1939ApJ....89..377K full text sources ADS | Related Materials (1) Reprint: 1939CMWCI.608....1K

Temperature Classification of Samarium Lines

view Abstract Citations (13) References Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Temperature Classification of Samarium Lines King, Arthur S. Abstract A temperature classification is given for ~iç~ samarium lines between X 2900 and X 8700. About 2800 of these belong to Sa I and ~2 fall into classes I and II, furnishing the basis for a term analysis. As with other rare earths, the furnace was highly effective in developing lines of the neutral spectrum, many of which are faint in the arc, and also gave the more sensitive lines of Sa ii, recognized through the comparison of furnace spectra with those of the arc and spark. Wave-lengths of the neutral lines were meas- ured in the furnace, a large proportion being new, and a checking of the earlier meas- ures of Sa II resulted in improved values in many cases, especially when close blends with neutral lines occur. In the arc, the relative strengths of the Sa i and Sa n spectra appeared to depend on the intensity of vaporization, governing the frequency of ionic combination. A strong ultra-violet spectrum peculiar to the spark probably arises from Sam. The doublet structure of many samarium lines, especially those of Sa ii, is described and measurements are given for the lines most clearly resolved. The explanation of this effect, probably a combination of isotope displacement and hyperfine structure, must await examination under high resolution Publication: The Astrophysical Journal Pub Date: September 1935 DOI: 10.1086/143664 Bibcode: 1935ApJ....82..140K full text sources ADS | Related Materials (1) Reprint: 1935CMWCI.523....1K

Photography of the Near Infra-Red Region of Stellar Spectra

This paper describes the chief features shown by a photographic reconnaissance of stellar spectra in the region XX 7000-9000 A, made with a plane-grating spectrograph attached to the 100-inch telescope. Most of the spectrograms are of dispersion 33 A/mm and show the region XX 83 20-8900, which is free from serious interference by terrestrial lines and includes a number of stellar lines of special interest. Results-Radial velocities from infra-red lines (Table VII) agree well with each other and with previous determinations from lines in the blue-violet region. The chief lines in the infra-red spectrum of a Cygni (Table II) are due to H, N i, o i, Mg ii, Ca u. The Paschen series of hydrogen lines is conspicuous in A-type spec- tra, especially those having the "c" characteristic, e.g., a Cygni, j3 Orionis. The lines of Ca ii XX 8498, 8542, 8662 are prominent in types A-M and may have an interesting relationship to absolute magnitude. They were found to be bright in the spectrum of R Hydrae. The 0 ilines XX 7772, 7774, 7775, and 8z~6 are important in types A and F. They appear very sensitive to absolute magnitude, being more intense in the brighter stars. Lines of neutral Ca, Ti, and Fe dominate spectra of classes K and M in the region XX 8320-8840. Many band heads were measured in spectra of class M. Most of them, especially in the X 7000 region, are due to TiO. A comparison of N-type spectra with furnace spectra taken by King shows that a large part of the complex structure between X 6910 and X 8780 is due to absorption by cyanogen

Temperature Classification of the Spectrum of Neodymium

The paper gives the temperature classification of 2863 neodymium lines in the spec- tral range XX 2963-7005, based on their relative intensities at three temperature stages of the electric furnace. The neutral spectrum, strong in the furnace, includes many lines that are faint in the arc, especially in the shorter wave-length region, a large proportion of which are now measured for the first time. The spectrum is notable for the large num- ber of lines in classes I and II, which are well developed at 2000° C, while the neutral lines in higher classes appear near 23000. The classification includes also the stronger lines of singly ionized neodymium, selected by comparing the furnace spectra with those of the arc and spark. A majority of these enhanced lines are present in the furnace spectrum at 2600°. Wave-lengths of 2026 lines were measured, comprising new neutral lines and others for which improved wave-lengths could be obtained. The dominance of the lines of Nd i, Nd it, and Nd iii in different spectral ranges is discussed. A comparison of neodymium spectrograms with those of samarium was made with reference to lines apparently common to both spectra, which might belong to the inter- mediate element 61. Lines of this character given by the samples used in this investiga- tion appear, however, to result from chance coincidences of true neodymium and samarium lines

Temperature Classification of the Stronger Lines of Columbium, with Preliminary Notes on Their Hyperfine Structure

view Abstract Citations (2) References Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Temperature Classification of the Stronger Lines of Columbium, with Preliminary Notes on Their Hyperfine Structure King, Arthur S. Abstract The paper gives the temperature ctass, the ionization, and a preliminary discussion of the hyperfine structure of 646 of the stronger lines of columbium between X 3100 and A 6900. The results were obtained by comparing electric-furnace spectra at tempera- tures of about 2500° and 29000 C with the spectra of the arc and spark. Approximately 200 lines appear in the furnace spectrum, but many neutral and all of the ionized lines require higher excitation. Much variation in response to excitation was found for lines in both groups: Of special interest is t/ze large proportion of columbium lines having /zyperfine structure. Of the lines listed, about 40 per cent are evidently complex. The patterns, for the most part unresolved, appear to consist usually of two, four, or six components, with some stifi more complex. As the wave-length increases, the spacing of hyperfine patterns becomes in general wider. Lines of complex structure occur in all temperature classes Publication: The Astrophysical Journal Pub Date: January 1931 DOI: 10.1086/143289 Bibcode: 1931ApJ....73...13K full text sources ADS | Related Materials (1) Reprint: 1931CMWCI.416....1K

Evidence from Band Spectra of the Existence of a Carbon Isotope of Mass 13

view Abstract Citations (13) References Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Evidence from Band Spectra of the Existence of a Carbon Isotope of Mass 13 King, Arthur S. ; Birge, Raymond T. Abstract Isotope C'3.-Evidence of the existence of this isotope appeared first in a faint band structure with head at X 4744.5, showing on electric-furnace spectrograms in which the Swan (C2) band A 4737 was of high intensity. The structure of the latter band being known, the displacements of the head and 15 component lines of the faint band were measured from corresponding lines of the primary band. An application of the quantum theory of band spectra then showed that the band A 4744.5 was due to a molecule C13C12, the emitter of X 4737 being the molecule C12C12. Further experimental work, together with examination of older material, showed that C'3 enters into molecules producing isotopic bands connected with the Swan band A 4332, the cyanogen bands A 3883 and A 3590, and the carbon monoxide bands be- tween A 1200 and X 1~00. The isotopic shift for the (io) band A ~7~7 has been studied in detail as far as the observational material permitted. The staggering of the main band, the presence of perturbations, and the methods of computing the vibrational and rotational shifts are discussed. The isotopic shift for this band is found to be about 7.6 A, and the algebraic mean of the differences 0- C is - 0.0096 A, or i part in 800, a difference within the errors of measurement. It follows from this that the mass ratio of the two carbon iso- topes is 12 to 13, accurate to about i part in 10,000. Other isotopic bands-A faint band structure to the red of the (2,0) band at A 4382 has a head with an isotopic shift of 12.58 A, agreeing closely with the calculated shift of 12.57 A. Ez~idence of a C'3N'4 molecule is found in the cyanogen band X 3883, where six faint lines evidently belong to an isotopic band, their measured shifts from corresponding primary 1i~es differing from the calculated by an average amount +0.0057 A. This small discrepancy may be due to an electronic isotope effect. The (i,o) band of this system, A 3590, also shows an isotopic band in the furnace spectrum, the observed shift from the primary head being 5.3 A, agreeing with the calculated shift of 5.30 A. These results incidentally furnish quantitative evidence that the emitters of the Swan and "cyanogen" bands are the C2 and CN molecules, respectively. -The relative abundance of C'~ and C12, estimated very roughly from photographic intensities of the bands, appears to be of the order I :400. Such estimates are rendered uncertain, however, by an apparent dependence on the method of excitation. The fur- nace and other low-excitation sources, notably N-type stars, are very effective in emitting the C'~ spectrum. In the arc, however, the only evidence of C'~ thus far is the group of lines in the cyanogen band X 3883, this band being emitted with extraordinary inten- sity by the arc. Conditions in the three typical sources-arc, furnace, and star-are dis- cussed with regard to their possible bearing on the excitation of bands in which C'3 is concerned. INTRODUCTIO Publication: The Astrophysical Journal Pub Date: July 1930 DOI: 10.1086/143257 Bibcode: 1930ApJ....72...19K full text sources ADS | Related Materials (1) Reprint: 1930CMWCI.402....1K

An Isotope of Carbon, Mass 13

THE bands belonging to the Swan spectrum of carbon appear in the vacuum electric furnace at about 2400° C. At temperatures above 2600° they are strong and clear-cut, even the band at λ6191, difficult to obtain in the carbon arc, being well defined. It has been noted by one of us, during a variety of electric furnace investigations, that plates on which the band at λ4737 is very strong showed a faint band, not to be ascribed to a ghost, about 7.5 A. to the red of the strong band. The carbon arc shows a scattered structure in this region, which is suppressed in the furnace. It has, however, thus far failed to give the faint band, which in the furnace spectrum shows a distinct structure, essentially identical with the structure of the main band.

An Isotope of Carbon, Mass 13

THE bands belonging to the Swan spectrum of carbon appear in the vacuum electric furnace at about 2400° C. At temperatures above 2600° they are strong and clear-cut, even the band at λ6191, difficult to obtain in the carbon arc, being well defined. It has been noted by one of us, during a variety of electric furnace investigations, that plates on which the band at λ4737 is very strong showed a faint band, not to be ascribed to a ghost, about 7.5 A. to the red of the strong band. The carbon arc shows a scattered structure in this region, which is suppressed in the furnace. It has, however, thus far failed to give the faint band, which in the furnace spectrum shows a distinct structure, essentially identical with the structure of the main band.

The Furnace Spectrum of Beryllium

A high-temperature vacuum furnace using tungsten for container, and heating elements as well, has been designed to study the furnace spectra of high melting point substances. The furnace spectrum of beryllium in both absorption and emission has been observed from $\ensuremath{\lambda}2150\mathrm{A}\ensuremath{-}7000\mathrm{A}$ and over a range of temperature up to 2500\ifmmode^\circ\else\textdegree\fi{}K. The prediction that the beryllium line 2348.62A is the first line of the principal series of singlets for the neutral atom has been successfully confirmed and the diffuse and the sharp series of singlets of this element discovered and tabulated.

TWO BAND-GROUPS APPEARING IN ELECTRIC FURNACE SPECTRA AND PROBABLY ASSOCIATED WITH CARBON

TWO BAND-GROUPS APPEARING IN ELECTRIC FURNACE SPECTRA AND PROBABLY ASSOCIATED WITH CARBON

The Electric Furnace Spectra of Vanadium and Chromium in the Ultra-Violet

The Electric Furnace Spectra of Vanadium and Chromium in the Ultra-Violet

The electric furnace spectrum of titanium in the ultraviolet : A.S. King. ( Astrophys. Jour., April, 1924.)

The electric furnace spectrum of titanium in the ultraviolet : A.S. King. ( Astrophys. Jour., April, 1924.)

The Electric Furnace Spectrum of Iron in the Ultra-Violet with Supplementary Data for the Blue and Violet

The Electric Furnace Spectrum of Iron in the Ultra-Violet with Supplementary Data for the Blue and Violet

THE LEADING FEATURES OF THE ELECTRIC FURNACE SPECTRUM OF SCANDIUM

THE LEADING FEATURES OF THE ELECTRIC FURNACE SPECTRUM OF SCANDIUM

The Variation with Temperature of the Electric Furnace Spectrum of Manganese

The Variation with Temperature of the Electric Furnace Spectrum of Manganese

Effect of Magnetic Field on Electric Furnace Spectra

Effect of Magnetic Field on Electric Furnace Spectra