An atlas of optical spectrophotometry of Wolf-Rayet carbon and oxygen stars

1987 ◽  
Vol 65 ◽  
pp. 459 ◽  
Author(s):  
Ana V. Torres ◽  
Philip Massey
Keyword(s):  
Optical Spectrophotometry

scholarly journals Chemical Abundances in Galactic Bulge Pn

1993 ◽  
Vol 155 ◽  
pp. 581-581 ◽  
Author(s):  
N.A. Walton ◽  
M.J. Barlow ◽  
R.E.S. Clegg
Keyword(s):  
Galactic Disk ◽  
Planetary Nebulae ◽  
Solar Neighbourhood ◽  
Galactic Bulge ◽  
Low Resolution ◽  
Chemical Abundances ◽  
The Mean ◽  
Optical Spectrophotometry ◽  
High Metallicity

We present abundance determinations, in particular of carbon, and C/O ratios, for 11 Galactic bulge planetary nebulae (PN) based on our low resolution UV data from IUE observations and optical spectrophotometry from the Anglo-Australian Telescope. We compare the observed abundances with those predicted by dredge-up theory for the high metallicity Galactic bulge. The sample abundances are also contrasted with the abundances found for PN in the Galactic disk. The mean C/O ratio for the bulge PN is significantly lower than that found for Galactic disk PN. Further, we present an abundance analysis of the very metal-poor bulge PN M2-29. From an analysis of the differential extinction found from the observed ratios of the He ii 1640,4686Å lines, we find that the ultraviolet reddening law towards the bulge is steeper than in the solar neighbourhood.

scholarly journals Energy Distribution of Optical Radiation Emitted by Electrical Discharges in Insulating Liquids

Energies ◽  
2020 ◽  
Vol 13 (9) ◽  
pp. 2172 ◽  
Author(s):  
Michał Kozioł
Keyword(s):  
Energy Distribution ◽  
Optical Radiation ◽  
Electric Discharges ◽  
Diagnostic Systems ◽  
Electrical Discharges ◽  
Insulating Liquids ◽  
Protection Systems ◽  
Surface Discharges ◽  
Optical Spectrophotometry ◽  
Natural Ester

This article presents the results of the analysis of energy distribution of optical radiation emitted by electrical discharges in insulating liquids, such as synthetic ester, natural ester, and mineral oil. The measurements of optical radiation were carried out on a system of needle–needle type electrodes and on a system for surface discharges, which were immersed in brand new insulating liquids. Optical radiation was recorded using optical spectrophotometry method. On the basis of the obtained results, potential possibilities of using the analysis of the energy distribution of optical radiation as an additional descriptor for the recognition of individual sources of electric discharges were indicated. The results can also be used in the design of various types of detectors, as well as high-voltage diagnostic systems and arc protection systems.

scholarly journals Radiation in the Optical and UHF Range Emitted by Partial Discharges

Energies ◽  
2019 ◽  
Vol 12 (22) ◽  
pp. 4334 ◽  
Author(s):  
Michał Kozioł ◽  
Łukasz Nagi ◽  
Michał Kunicki ◽  
Ireneusz Urbaniec
Keyword(s):  
Electromagnetic Waves ◽  
Electrical Power ◽  
Partial Discharges ◽  
Radio Waves ◽  
Insulation Systems ◽  
Surface Discharges ◽  
High Voltage Insulation ◽  
Solid Dielectrics ◽  
Electrode Systems ◽  
Optical Spectrophotometry

This paper presents the results of analysis of a solid dielectric’s influence on the phenomena associated with the signals emitted by surface partial discharges. Three types of electrode systems were tested, in which solid dielectrics made of pressboard, Teflon, and glass were used. The emission of such signals as radio waves in the Ultra high frequency (UHF) range and optical radiation was analyzed. The measurements were carried out in the insulation systems most commonly used in electrical power equipment, i.e., mineral oil and air. UHF and optical spectrophotometry methods were used to register the emitted signals. The obtained results indicate that the type of material from which the dielectric solid is made may have a potential impact on some ranges of emitted electromagnetic waves during the surface electrical discharges. The research topic undertaken is important in issues associated with high-voltage insulation systems and in particular with surface discharges, which are often the cause of their damage.

scholarly journals FUV and optical spectrophotometry of X-ray selected Seyferts

1986 ◽  
Vol 119 ◽  
pp. 347-348
Author(s):  
J. T. Clarke ◽  
S. Bowyer ◽  
M. Grewing
Keyword(s):  
Seyfert Galaxies ◽  
Continuum Emission ◽  
Balmer Line ◽  
X Ray ◽  
Positive Correlation ◽  
Optical Spectrophotometry ◽  
Distinguishing Features ◽  
The Continuum

Nearly simultaneous FUV and optical spectrophotometry of X-ray selected Seyfert galaxies has revealed an average Ly α/H β ratio of 22, a positive correlation between the ratio Ly α/H β and the width of the lines, and additional Ly α emission in the wings of one source which is not matched by emission in the Balmer line wings. However, we find no distinguishing features in the continuum emission from these X-ray selected objects compared with other samples. If the correlation between Ly α/H β and the width of the lines is found to apply to larger samples of Seyferts, it may be that our objects appear Ly α bright because they are also broad-lined compared with other samples.

Optical spectrophotometry of the suspected X-ray cluster of galaxies E 1455 + 2232

1981 ◽  
Vol 86 ◽  
pp. 803 ◽  
Author(s):  
K. O. Mason ◽  
H. Spinrad ◽  
S. Bowyer ◽  
G. Reichert ◽  
J. Stauffer
Keyword(s):  
X Ray ◽  
Cluster Of Galaxies ◽  
Optical Spectrophotometry

Uranium Redox States in Borosilicate Compositions

2004 ◽  
Vol 824 ◽  
Author(s):  
A.S. Aloy ◽  
A.V. Trofimenko ◽  
O.A. Iskhakova ◽  
L.J. Jardine
Keyword(s):  
Solid State ◽  
Borosilicate Glasses ◽  
X Ray Diffraction ◽  
X Ray ◽  
Synthesis Conditions ◽  
Redox States ◽  
Nuclear Gamma Resonance ◽  
Reducing Conditions ◽  
Optical Spectrophotometry

AbstractThe results of the studies of uranium valent states in the borosilicate glasses incorporating the components of uranium-containing sludge of Mining and Chemical Combine (MCC, Zheleznogorsks.) is presented in this work. The glasses were made under oxidative and reducing conditions.The optical spectrophotometry, nuclear gamma-resonance (NGR) and X-ray diffraction (XRD) showed that glasses produced under oxidative conditions are characterized by the presence of only U(6+), while U(4+) in the reducing conditions is present along with U(6+). The ratio U(6+)/to U(4+) varies in depending on the synthesis conditions.The glass samples synthesized under oxidative conditions were researched at initial solid state. The others synthesized under reducing conditions was dissolved preliminary without distort of uranium valency.The effect of U(4+)/U(6+) ratio on the uranium leach rates from the glasses has been studied at 90° using MCC-1 test.

scholarly journals Optical Spectrophotometry of Nova PW Vulpeculae

1990 ◽  
Vol 122 ◽  
pp. 159-160 ◽  
Author(s):  
J. Mikołajewska ◽  
M. Mikołajewski
Keyword(s):  
Spectral Sensitivity ◽  
Spectral Range ◽  
Atmospheric Extinction ◽  
Absolute Flux ◽  
Classical Nova ◽  
The Absolute ◽  
Cassegrain Telescope ◽  
Optical Spectrophotometry ◽  
Low Dispersion ◽  
Flux Calibration

PW Vul (Nowa Vul 1984 #1) was a slow classical nova which began its outburst in July 1984 and reached optical maximum in the first week of August 1984. Eight low dispersion spectra (160 A/mm) in the blue spectral range (λλ3400-5100 A) were secured between October 1984 and July 1985, with the CCS spectrograph equipped with 3.5 arcsec aperture image slicer and mounted on 90 cm Schmidt-Cassegrain telescope at Toruń Observatory. Kodak IIa-O plates were used. In addition two moderate dispersion (40 A/mm) spectra in the Hγ-Hβ range were obtained on 28 October and 3 November 1984, using the same instrumentation. Standard stars were observed on each night to remove the influence of spectral sensitivity of the photographic emulssion and atmospheric extinction. The calibration of the absolute flux scale was performed by comparing synthetic B magnitudes calculated from our spectra with published B photometry of PW Vul (Voloshina 1985, Noskova et al. 1985, Kolotilov and Noskova 1986). The accuracy of the flux calibration is ±0.1 mag.

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