scholarly journals Analysis of UV spectrophotometric observations for O-type stars.

1979 ◽  
Vol 83 ◽  
pp. 109-112
Author(s):  
Carlo Morossi ◽  
Roberto Stalio ◽  
Lucio Crivellari
Keyword(s):  
Wavelength Range ◽  
Spectral Resolution ◽  
Bright Star ◽  
Stellar Spectra ◽  
Different Temperatures ◽  
Far Ultraviolet

The ESA “Ultraviolet Bright Star Spectrophotometric Catalogue” (Jamar et al. 1976) and the “Catalogue of 0.2 A Resolution Far-ultraviolet Stellar Spectra Measured with Copernicus” (Snow and Jenkins 1976) have been used to try to separate, by means of simple diagrams, O-type stars belonging to different luminosity classes and having different temperatures. The ESA catalogue gives absolute fluxes for 43 O-type stars, mostly reddened, with a spectral resolution of 35–40 A, depending on the channel, in the wavelength range 1350–2550 A. The Copernicus catalogue gives spectra between 1000 and 1450 A for 17 O-type stars, with low reddening, at 0.2 A resolution.

A Discussion on astronomy in the ultraviolet - Skylark rocket observations of ultraviolet spectra of γ 2 Velorum and ζ Puppis

1975 ◽  
Vol 279 (1289) ◽  
pp. 355-369 ◽  
Keyword(s):  
Wavelength Range ◽  
Spectral Resolution ◽  
High Velocity ◽  
Stellar Atmospheres ◽  
Photographic Film ◽  
Line Of Sight ◽  
Line Profiles ◽  
Interstellar Gas ◽  
Stellar Spectra ◽  
Ultraviolet Spectra

A star-stabilized Skylark rocket was launched from Woomera in June 1973 to record ultraviolet spectra of the bright stars y 2 Velorum and £ Puppis. The instrumentation consisted of three Wadsworth-mounted objective grating spectrographs with a combined wavelength range 90-230 nm. Stellar spectra were recorded on Kodak 101-01 photographic film, the in-flight spectral resolution being approximately 30 pm. Two exposures were obtained on each of the target stars. The y 2 Vel spectrum observations extend from 92 to 230 nm and the £ Pup spectrum from 100 to 230 nm. Analysis of the spectra provides information about the composition and properties of the interstellar gas in the line of sight. The observations also provide useful data on the stellar atmospheres. P Cygni line profiles are observed in the spectra of both stars indicating that high velocity material is being ejected.

scholarly journals A Catalogue of 0.2 Å Resolution Far-Ultraviolet Stellar Spectra Measured with Copernicus

1977 ◽  
Vol 4 (2) ◽  
pp. 353-354
Author(s):  
Theodore P. Snow ◽  
Edward B. Jenkins
Keyword(s):  
Wavelength Range ◽  
Comparative Studies ◽  
Step Length ◽  
Line Profiles ◽  
Stellar Spectra ◽  
Modes Of Presentation ◽  
Astrophysical Journal ◽  
Visible Spectra ◽  
Far Ultraviolet ◽  
Nominal Resolution

Of the nearly 300 stars which have been observed in the ultraviolet with Copernicus, 60 have been chosen for publication of their complete intermediate-resolution spectra, which consist of scans made with photomultiplier U2 at a nominal resolution and step length of 0.2 Å. The spectra cover the wavelength range 1000 to 1450 Å and are expressed in the form of direct numerical tabulations, compressed-scale plots, and synthetic photographic spectrograms. These three modes of presentation are expected to satisfy the needs of various types of research on stellar spectra, ranging from detailed and rather specialized analyses of line profiles, which require accurate numerical results, to broad, comparative studies of various qualitative features over different spectral types, for which the plots or photographs are best suited. From the qualitative comparisons one might expect to synthesize more exacting criteria for spectral classifications of normal stars, using ultraviolet instead of visible spectra. The catalogue has been submitted for publication in the Astrophysical Journal Supplements.

scholarly journals Far-Ultraviolet Objective Spectrographic Surveys for Mapping of Interstellar H2, H, and CO

1980 ◽  
Vol 87 ◽  
pp. 611-612
Author(s):  
George R. Carruthers
Keyword(s):  
Wavelength Range ◽  
Spectral Resolution ◽  
Wide Field ◽  
Early Type ◽  
Visual Magnitude ◽  
Early Type Stars ◽  
Far Ultraviolet

A far-ultraviolet, wide-field camera/spectrograph investigation has been proposed for Spacelab missions. By use of an objective grating, this experiment could survey large areas of the sky, obtaining spectra of early-type stars as faint as 12th visual magnitude in the 950-2000 Å wavelength range, with 1 to 2 Å spectral resolution.

scholarly journals FUSE Observations of Mass Loss in Planetary Nebulae

2003 ◽  
Vol 209 ◽  
pp. 187-188 ◽  
Author(s):  
Rosina Iping ◽  
George Sonneborn
Keyword(s):  
Mass Loss ◽  
Wavelength Range ◽  
Spectral Resolution ◽  
Planetary Nebulae ◽  
Far Ultraviolet

The Far Ultraviolet Spectroscopic Explorer (FUSE) satellite observed several high and low excitation planetary nebulae in the wavelength range 905–1187 Å at a spectral resolution of λ/Δλ ~ 15,000.

scholarly journals Comprehensive modeling of bloodstain aging by multivariate Raman spectral resolution with kinetics

2019 ◽  
Vol 2 (1) ◽  
Author(s):  
Ayari Takamura ◽  
Daisuke Watanabe ◽  
Rintaro Shimada ◽  
Takeaki Ozawa
Keyword(s):  
Spectral Resolution ◽  
Aging Process ◽  
Near Infrared ◽  
Biochemical Characterization ◽  
Forensic Analysis ◽  
Chemical Mechanism ◽  
Experimental Conditions ◽  
Spectral Components ◽  
Different Temperatures ◽  
Analytical Approaches

Abstract Blood, as a cardinal biological system, is a challenging target for biochemical characterization because of sample complexity and a lack of analytical approaches. To reveal and evaluate aging process of blood compositions is an unexplored issue in forensic analysis, which is useful to elucidate the details of a crime. Here we demonstrate a spectral deconvolution model of near-infrared Raman spectra of bloodstain to comprehensively describe the aging process based on the chemical mechanism, particularly the kinetics. The bloodstain spectra monitored over several months at different temperatures are decomposed into significant spectral components by multivariate calculation. The kinetic schemes of the spectral components are explored and subsequently incorporated into the developed algorithm for the optimal spectral resolution. Consequently, the index of bloodstain aging is proposed, which can be used under different experimental conditions. This work provides a novel perspective on the chemical mechanisms in bloodstain aging and facilitates forensic applications.

scholarly journals High-Dispersion Spectroscopy of the Brightest Emission-Line Stars of the Magellanic Clouds

1986 ◽  
Vol 116 ◽  
pp. 247-248 ◽  
Author(s):  
O. Stahl ◽  
B. Wolf ◽  
M. de Groot ◽  
C. Leitherer
Keyword(s):  
Emission Line ◽  
Wavelength Range ◽  
Spectral Resolution ◽  
Magellanic Clouds ◽  
High Dispersion

We present an atlas of high dispersion spectra of 24 of the brightest peculiar emission-line stars of the Magellanic Clouds.Our spectra cover the wavelength range from 3600 to 4900 Å. They have been obtained from 1970 to 1984 with the coudé spectrograph of the ESO 1.52 m telescope at La Silla, Chile. The spectral resolution is 0.4 Å for most of the spectra and 0.2 Å for the very brightest stars. Up to 11 spectra are available for one star. In addition, we have done UBVRIJHK(LM) photometry at several epochs of all stars of our sample.

scholarly journals Expected Scientific Performance of the Three Spectrometers on the Extreme Ultraviolet Explorer

1990 ◽  
Vol 115 ◽  
pp. 335-338
Author(s):  
J. V. Vallerga ◽  
P. Jelinsky ◽  
P. W. Vedder ◽  
R. F. Malina
Keyword(s):  
Wavelength Range ◽  
Spectral Resolution ◽  
Line Source ◽  
White Dwarfs ◽  
Extreme Ultraviolet ◽  
Cataclysmic Variables ◽  
Effective Area ◽  
Light Sources ◽  
Scientific Performance ◽  
Astronomical Satellite

AbstractThe expected in-orbit performance of the three spectrometers included on the Extreme Ultraviolet Explorer (EUVE) astronomical satellite is presented. Recent calibrations of the gratings, mirrors and detectors using monochromatic and continuum EUV light sources allow the calculation of the spectral resolution and throughput of the instrument. An effective area range of 0.2 to 2.8 cm2 is achieved over the wavelength range 70-600Å with a peak spectral resolution λ/Δλ (FWHM) of ~ 360 assuming a spacecraft pointing knowledge of 10 arc seconds (FWHM). For a 40,000 sec observation, the average 3σ sensitivity to a monochromatic line source is 3 × 103 photons cm-2 sec-1. Simulated observations of known classes of EUV sources such as hot white dwarfs and cataclysmic variables are also presented.

scholarly journals A Spectropolarimetric Atlas of 61 Bright Northern Be Stars

2000 ◽  
Vol 175 ◽  
pp. 48-50 ◽  
Author(s):  
Karen S. Bjorkman ◽  
Marilyn R. Meade ◽  
Brian L. Babler
Keyword(s):  
Wavelength Range ◽  
Spectral Resolution ◽  
Wavelength Dependence ◽  
Be Stars ◽  
University Of Wisconsin ◽  
Time Period ◽  
Ccd Detector ◽  
Ccd Observations ◽  
Full Analysis ◽  
The University

AbstractWe are developing an atlas of spectropolarimetric observations of 61 bright northern Be stars obtained from 1989-94 using the halfwave polarimeter (HPOL) at the 0.9m telescope of the University of Wisconsin Pine Bluff Observatory (PBO). The data cover the wavelength range from about 3400-7600Å, with a spectral resolution of about 25Å. This atlas will contain all data (297 observations total) obtained as part of a survey program with HPOL during the time when the detector in use was a dual Reticon array; the survey observations with HPOL continue, using a new CCD detector which extends the spectral coverage out to 1.05μm and improves the spectral resolution to about 12Å. The CCD observations will be presented later in a second volume of the atlas.Only a brief summary of the findings of the survey from the first 5 years of the project is presented here. A full analysis of the data will be included in a paper to be published elsewhere. The general wavelength dependence of polarization for classical Be stars can be considered on the basis of these observations, and results on polarimetric variability are available. In particular, we find that 56% (20 of 36) of the Be stars observed 3 or more times from 1989-94 show significantly variable polarization at the level of 0.1% changes (inclusion of preliminary results from the continuing CCD survey indicates that the percentage is even higher). The timescales for these changes range from as short as night-to-night to as long as several months. Several of the stars showed evidence for polarimetric “outbursts” during the time period covered by the observations.

Sign in / Sign up

Export Citation Format

Share Document