High-resolution ultraviolet spectra of sympathetically-laser-cooledCd+ions

1996 ◽  
Vol 53 (1) ◽  
pp. 122-125 ◽  
Author(s):  
Hidetsuka Imajo ◽  
Kazuhiro Hayasaka ◽  
Ryuzo Ohmukai ◽  
Utako Tanaka ◽  
Masayoshi Watanabe ◽  
...  
Keyword(s):  
High Resolution ◽  
Ultraviolet Spectra

scholarly journals IUE Ultraviolet Spectra of the Interacting Binary U Cephei

1980 ◽  
Vol 88 ◽  
pp. 237-241
Author(s):  
Yoji Kondo ◽  
George E. McCluskey ◽  
Robert E. Stencel
Keyword(s):  
High Resolution ◽  
Ultraviolet Light ◽  
Stellar Evolution ◽  
Binary Systems ◽  
Light Curves ◽  
Close Binary ◽  
Eclipsing Binary ◽  
Ultraviolet Spectra ◽  
International Ultraviolet Explorer ◽  
Far Ultraviolet

The eclipsing binary U Cephei has proven to be of great interest in the study of stellar evolution in close binary systems. Batten (1974), Hall and Walter (1974), Rhombs and Fix (1976), Markworth (1977), and Olson (1978), among others, have recently reported on their intensive ground based studies of U Cephei. Kondo, McCluskey and Wu (1978) have investigated the ultraviolet light curves of U Cephei obtained with Astronomical Netherlands Satellite (ANS). Kondo, McCluskey and Stencel (1979) have discussed the International Ultraviolet Explorer (IUE) spectra of U Cephei. This paper discusses results incorporating additional IUE high resolution spectra of U Cephei obtained in both far-ultraviolet and mid-ultraviolet spectral regions.

The Dynamical State of the Atmosphere of the Supergiant Alpha Cygni (A2 Iae) Derived from High-Resolution Ultraviolet Spectra

1988 ◽  
Vol 102 ◽  
pp. 383-386
Author(s):  
B. Boer ◽  
C. de Jager ◽  
H. Nieuwenhuijzen
Keyword(s):  
High Resolution ◽  
Velocity Profile ◽  
Optical Depth ◽  
Velocity Component ◽  
Line Of Sight ◽  
Velocity Of Sound ◽  
Ultraviolet Spectra ◽  
Dynamical State ◽  
Microturbulent Velocity ◽  
Visible Disk

AbstractIn order to study the apparent near instability of supergiant atmospheres high-resolution (λ/Δ λ = 8×104) BUSS (Balloon-borne Ultraviolet Stellar Spectrometer) spectra of the supergiant Alpha Cyg have been investigated. Equivalent widths of lines yield the variation of the line-of-sight microturbulent velocity component ζµwith optical depth τ. We find at τ5= 0.1: ζµequal to the velocity of sound. The consequent turbulent acceleration is directed outward, it increases outward and is about half the effective acceleration at τ5= 0.01. The macroturbulent velocity profile is double peaked with up- and downward velocities of 14 km s−1. We suggest that these motions are stochastic pulsations of large elements. At any time there are 30 to 40 such elements on the visible disk.

First results from the Goddard High-Resolution Spectrograph - Ultraviolet spectra of a starburst knot in NGC 1068

1991 ◽  
Vol 377 ◽  
pp. L25 ◽  
Author(s):  
J. B. Hutchings ◽  
F. Bruhweiler ◽  
A. Boggess ◽  
S. R. Heap ◽  
D. Ebbets ◽  
...  
Keyword(s):  
High Resolution ◽  
Ultraviolet Spectra ◽  
First Results ◽  
Ngc 1068

scholarly journals The Very Unusual Ultraviolet Spectra of R Arae

1982 ◽  
Vol 69 ◽  
pp. 321-326
Author(s):  
Yoji Kondo ◽  
George E. McCluskey
Keyword(s):  
High Resolution ◽  
X Ray ◽  
Ultraviolet Spectra ◽  
International Ultraviolet Explorer ◽  
Flux Level ◽  
Orbital Cycle

AbstractThe high resolution ultraviolet spectra of the 4.4-day period binary R Arae, observed in 1980 with the International Ultraviolet Explorer (IUE), show that its continuum flux level varied outside of eclipse by more than a factor of two in ten days, and by over 50 percent within a same orbital cycle. The flux level varied non-monotonically at different wavelengths. The resonance lines of Mg II and Si IV exhibited shortward–shifted absorption components near phase 0.4, indicating the presence of a gas stream toward the observer at a velocity of some –450 to –500 km s–1. Our observations of R Arae with the Einstein satellite show it to be an X–ray source.

scholarly journals High‐Resolution Ultraviolet Spectra of the Dwarf Seyfert 1 Galaxy NGC 4395: Evidence for Intrinsic Absorption

2004 ◽  
Vol 612 (1) ◽  
pp. 152-158 ◽  
Author(s):  
D. M. Crenshaw ◽  
S. B. Kraemer ◽  
J. R. Gabel ◽  
H. R. Schmitt ◽  
A. V. Filippenko ◽  
...  
Keyword(s):  
High Resolution ◽  
Ultraviolet Spectra ◽  
Intrinsic Absorption ◽  
Ngc 4395

High-resolution imaging spectrometer for recording absolutely calibrated far ultraviolet spectra from laser-produced plasmas

2008 ◽  
Vol 79 (10) ◽  
pp. 103109 ◽  
Author(s):  
Charles M. Brown ◽  
John F. Seely ◽  
Uri Feldman ◽  
Glenn E. Holland ◽  
James L. Weaver ◽  
...  
Keyword(s):  
High Resolution ◽  
High Resolution Imaging ◽  
Imaging Spectrometer ◽  
Ultraviolet Spectra ◽  
Resolution Imaging ◽  
Far Ultraviolet

scholarly journals High-Velocity Absorption Components Toward the LMC

1989 ◽  
Vol 120 ◽  
pp. 383-388 ◽  
Author(s):  
G. Vladilo ◽  
P. Molaro ◽  
S. Monai ◽  
M. Centurion
Keyword(s):  
Detection Limit ◽  
High Resolution ◽  
High Velocity ◽  
Column Density ◽  
The Other ◽  
General Direction ◽  
Ultraviolet Spectra ◽  
Broad Component ◽  
Hydrogen Column Density ◽  
First Time

AbstractHigh-resolution (λ/δλ ⋍ 6 x 104) spectra of R136 (the central object of 30 Dor) and of 2 LMC supergiants obtained at ESO with the 1.4-m telescope have been analysed in order to study the high-velocity absorption components at VLSR ⋍ +60 km s-1 and ⋍ +130 km s-1 first seen in satellite ultraviolet spectra in the general direction of the LMC. Our data have been integrated with previous literature results of SN1987a and of other 4 LMC supergiants obtained from spectra of similar spectral resolution.At least 6 (possibly 9) interstellar components are found in the range +40 km s-1 ≤ VISR ≤ + 150 km s-1, suggesting that the IUE features at ⋍ +60 km s-1 and ⋍ +130 km s-1 are in fact splitted in several components when observed at higher resolution. Two components originally discovered toward SN1987a (VLSR ⋍ +42 km s-1 and +107 km s-1), are detected for the first time in the Call interstellar spectrum of R136. A component at VLSR ⋍ +49 km s-1 shows significant variations both in Call and in Nal along the different lines of sight. A relatively broad component at VLSR ⋍ +58 km s-1 is present in Call toward R136, but is generally undetected in Nal in the other lines of sight. Also the components in the range +100 km s-1 ≤ VLSR ≤ +150 km s-1 are detected in Call, but not in Nal. Two weak absorptions, detected at +125 km s-1 and +141 km s-1 toward R136, may be associated with the ⋍ +130 km s-1 component characteristic of the ultraviolet spectra.The almost perfect velocity coincidence of the +107 km s-1, +42 km s-1, +49 km s-1 and +57 km s-1 components along different lines of sight suggests a common origin of the absorbing gas and a location close to our Galaxy. In spite of the low detection limit in our spectra (Wλ ⋍ 5 mÅ), the lack of detection of Nal is compatible with the presence of foreground gas clouds with hydrogen column density N(HI) ≤ 2 x 1019 cm-2, or even greater. The fact that we can detect more easily Call absorptions than the corresponding Nal absorptions indicates a very low value of Call depletion.

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