Spectroscopy of the double quasars Q1343+266A, B: The relationship between galaxies and quasi-stellar object C IV absorption lines

1994 ◽  
Vol 437 ◽  
pp. L79 ◽  
Author(s):  
Arlin P. S. Crotts ◽  
Jill Bechtold ◽  
Yihu Fang ◽  
Robert C. Duncan
Keyword(s):  
Stellar Object ◽  
Absorption Lines ◽  
The Relationship

Absorption Lines in the Spectra of the QSO PKS 1448-232

1984 ◽  
Vol 5 (3) ◽  
pp. 355-359 ◽  
Author(s):  
Chen Jian-sheng ◽  
Donald C. Morton ◽  
Bruce A. Peterson ◽  
Alan E. Wright ◽  
David L. Jauncey
Keyword(s):  
Radio Source ◽  
Stellar Object ◽  
Absorption Lines ◽  
Ultraviolet Excess ◽  
Low Resolution ◽  
Optical Position

Savage et al. (1977) found that the radio source PKS 1448-232 coincided with a stellar object of about magnitude 16.4 having an ultraviolet excess. A low resolution spectrum obtained with the Anglo-Australian Telescope (AAT) confirmed this object as a QSO with zem = 2.22 and revealed many absorption lines short-ward of the La emission. Consequently this object was included in a programme of spectroscopy at intermediate resolution with the AAT to investigate QSO absorption lines. Savage et al. have given a finding chart with an optical position of 14h48m09s.3, −23°17′10″ (1950.0). The radio fluxes are 0.40 Jy at 2.7 GHz and 0.31 Jy at 5.0 GHz.

The origin of the quasi-stellar object absorption lines

1991 ◽  
Vol 377 ◽  
pp. 39 ◽  
Author(s):  
S. M. Viegas ◽  
R. B. Gruenwald
Keyword(s):  
Stellar Object ◽  
Absorption Lines

scholarly journals The Relationship of the Oe to the Be Stars

1976 ◽  
Vol 70 ◽  
pp. 139-147 ◽  
Author(s):  
Stewart A. Frost ◽  
Peter S. Conti
Keyword(s):  
Formation Mechanism ◽  
Main Sequence ◽  
Absorption Lines ◽  
Be Stars ◽  
Line Profiles ◽  
Broad Absorption ◽  
Hydrogen Lines ◽  
Relationship Of ◽  
The Relationship ◽  
Narrow Emission

Oe stars are earlier type analogues of the better known Be class. These stars have relatively narrow emission in the hydrogen lines and sometimes in the helium lines, which often appears to be double. In several Oe stars, the emission is intermittent. Other properties of the class include relatively broad absorption lines and luminosities near the main sequence. Line profiles in three representative Oe stars are presented and discussed. The similarity of the spectra of Oe and Be stars suggests that the formation mechanism for the emitting region, whatever it is, must extend to the mid O-type stars, at least.

High‐Resolution Spectra of Intrinsic Absorption Lines in the Quasi‐stellar Object UM 675

1997 ◽  
Vol 478 (1) ◽  
pp. 80-86 ◽  
Author(s):  
Fred Hamann ◽  
Thomas A. Barlow ◽  
Vesa Junkkarinen ◽  
E. M. Burbidge
Keyword(s):  
High Resolution ◽  
Stellar Object ◽  
Absorption Lines ◽  
Intrinsic Absorption

Time‐variable Intrinsic Absorption Lines in the Quasi‐stellar Object Q2343+125

1997 ◽  
Vol 478 (1) ◽  
pp. 87-93 ◽  
Author(s):  
Fred Hamann ◽  
Thomas A. Barlow ◽  
Vesa Junkkarinen
Keyword(s):  
Time Variable ◽  
Stellar Object ◽  
Absorption Lines ◽  
Intrinsic Absorption

Interstellar gas in the central region of the Galaxy

1967 ◽  
Vol 31 ◽  
pp. 239-251 ◽  
Author(s):  
F. J. Kerr
Keyword(s):  
Central Region ◽  
Galactic Plane ◽  
Neutral Hydrogen ◽  
Continuum Emission ◽  
Galactic Centre ◽  
Interstellar Gas ◽  
Hydrogen Recombination ◽  
The Galaxy ◽  
Centre Region ◽  
The Relationship

A review is given of information on the galactic-centre region obtained from recent observations of the 21-cm line from neutral hydrogen, the 18-cm group of OH lines, a hydrogen recombination line at 6 cm wavelength, and the continuum emission from ionized hydrogen.Both inward and outward motions are important in this region, in addition to rotation. Several types of observation indicate the presence of material in features inclined to the galactic plane. The relationship between the H and OH concentrations is not yet clear, but a rough picture of the central region can be proposed.

The relationship of the scleractinian corals to the rugose corals

Paleobiology ◽  
1980 ◽  
Vol 6 (02) ◽  
pp. 146-160 ◽  
Author(s):  
William A. Oliver
Keyword(s):  
Critical Points ◽  
Scleractinian Corals ◽  
Convincing Evidence ◽  
Early Triassic ◽  
Rugose Corals ◽  
History Of ◽  
The Subject ◽  
Relationship Of ◽  
The Relationship ◽  
Biologic Factors

The Mesozoic-Cenozoic coral Order Scleractinia has been suggested to have originated or evolved (1) by direct descent from the Paleozoic Order Rugosa or (2) by the development of a skeleton in members of one of the anemone groups that probably have existed throughout Phanerozoic time. In spite of much work on the subject, advocates of the direct descent hypothesis have failed to find convincing evidence of this relationship. Critical points are:(1) Rugosan septal insertion is serial; Scleractinian insertion is cyclic; no intermediate stages have been demonstrated. Apparent intermediates are Scleractinia having bilateral cyclic insertion or teratological Rugosa.(2) There is convincing evidence that the skeletons of many Rugosa were calcitic and none are known to be or to have been aragonitic. In contrast, the skeletons of all living Scleractinia are aragonitic and there is evidence that fossil Scleractinia were aragonitic also. The mineralogic difference is almost certainly due to intrinsic biologic factors.(3) No early Triassic corals of either group are known. This fact is not compelling (by itself) but is important in connection with points 1 and 2, because, given direct descent, both changes took place during this only stage in the history of the two groups in which there are no known corals.

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