THE DYNAMICAL STATE OF THE ATMOSPHERE OF THE SUPERGIANT ALPHA CYGNI (A2 Iae) DERIVED FROM HIGH-RESOLUTION ULTRAVIOLET SPECTRA

1988 ◽  
Vol 49 (C1) ◽  
pp. C1-383-C1-386
Author(s):  
B. BOER ◽  
C. de JAGER ◽  
H. NIEUWENHUIJZEN
Keyword(s):  
High Resolution ◽  
Ultraviolet Spectra ◽  
Dynamical State

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.

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.

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

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 FM 22. Mapping the Frontier Fields with Chandra X-ray Observations

2015 ◽  
Vol 11 (A29B) ◽  
pp. 758-759
Author(s):  
C. Jones ◽  
R. van Weeren ◽  
G. Ogrean ◽  
W. Forman
Keyword(s):  
Dark Matter ◽  
High Resolution ◽  
X Ray ◽  
Hot Gas ◽  
Cold Fronts ◽  
Dynamical State ◽  
Cluster Morphology ◽  
Cluster Mergers ◽  
Relativistic Particles ◽  
Resolution Mass

AbstractChandra has deeply observed the clusters and parallel fields in four Frontier Fields. These observations allow us to dramatically improve our understanding of cluster mergers by comparing the detailed mapping of the hot cluster gas with high resolution mass maps and by identifying merger shocks and cold fronts. In merging clusters, relativistic particles can be re-accelerated to produce radio relics. A comparison of lensing maps and Chandra images allows us to determine the cluster morphology and dynamical state and if there are offsets between the dark matter and the hot gas.

scholarly journals MASSIVE QUIESCENT CORES IN ORION: DYNAMICAL STATE REVEALED BY HIGH-RESOLUTION AMMONIA MAPS

2013 ◽  
Vol 768 (1) ◽  
pp. L5 ◽  
Author(s):  
D. Li ◽  
J. Kauffmann ◽  
Q. Zhang ◽  
W. Chen
Keyword(s):  
High Resolution ◽  
Dynamical State

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
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