Results 201 to 210 of about 2,644 (226)

Rapid Temporal Variations of Interstellar Absorption Lines in the Carina Nebula

The Astrophysical Journal, 2001
Two observations of the complex interstellar absorption-line profiles in the UV spectrum of CPD -59°2603, obtained 22 months apart in the R ~ 110,000 mode of the Space Telescope Imaging Spectrograph on the Hubble Space Telescope, reveal substantial variations in the intensities of several high-velocity components, including the virtual disappearance of
Anthony C. Danks, Nolan R. Walborn, Gladys Vieira, Wayne B. Landsman, Joel Gales, Beatriz García   +5 more
openaire   +1 more source

Absorption Lines from Intermediate-Latitude Interstellar Complexes

Publications of the Astronomical Society of the Pacific, 1966
Recent observations of the 21 cm emission line of hydrogen ( Blaauw 1962) have revealed the existence of massive interstellar cloud complexes at considerable distances from the galactic plane. The region 126° < ln < 142°, -19° < bn < -7°, near the association I Persei, in particular, shows a high level of emission at velocities of -48 km/sec (feature ...
openaire   +1 more source

Determination of distances to interstellar clouds using OH absorption lines

Astrophysics, 1984
An attempt is made to determine distances to interstellar clouds by a method free of the limitations of the conventional method (using the galactic rotation curve). It is shown that the term delta, given by the square root of the ratio of the half width of the OH absorption lines to the antenna temperature, varies linearly with the distance R to the ...
I. G. Kolesnik, L. V. Yurevich
openaire   +1 more source

A Discussion on astronomy in the ultraviolet - Interstellar molecular absorption lines

Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences, 1975
Abstract The ultraviolet absorption lines produced in interstellar clouds through the absorption of radiation from early type stars by molecular hydrogen H2 may be analysed to yield the particle densities and ultraviolet fluxes in the absorbing regions and the absorption by HD may be analysed to determine the proton densities and the ...
openaire   +1 more source

Tentative identification of the diffuse interstellar absorption bands and of a diffuse interstellar doublet line

Astrophysics and Space Science, 1969
The four diffuse interstellar absorption bands at λ4430, λ4760, λ4890, and λ6180 and the two diffuse lines at λ5780 and λ5797 are interpreted as belonging to pre-ionization transitions in H− and O−, respectively. In both cases the identifications are supported by extrapolations of wave numbers of resonance lines along isoelectronic sequences.
openaire   +1 more source

Line Absorption Studies of the Interstellar Gas Near 10¹⁵ Hz

Symposium - International Astronomical Union, 1974
The Copernicus satellite now opens up the ultraviolet region for inspection, and the number of resonance lines which may be studied has increased from 6, seen in the visible, to more than 30. The distribution and properties of an important constituent of the interstellar gas, molecular hydrogen, can be studied in detail using this instrument.
openaire   +1 more source

Detection of PAH Absorption and Determination of the Mid-infrared Diffuse Interstellar Extinction Curve from the Sight Line toward Cyg OB2-12

Astrophysical Journal, 2020
Brandon S Hensley, B T Draine
exaly  

Interstellar Absorption Lines

2004
openaire   +1 more source

INTERSTELLAR ABUNDANCES FROM ABSORPTION-LINE OBSERVATIONS WITH THEHUBBLE SPACE TELESCOPE

Annual Review of Astronomy and Astrophysics, 1996
Blair D Savage, Kenneth R Sembach
exaly  

New aspects of absorption line formation in intervening turbulent clouds -- II. Monte Carlo simulation of interstellar H+D Ly  absorption profiles

Monthly Notices of the Royal Astronomical Society, 1997
S A Levshakov, W H Kegel, I E Mazets
exaly