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On interstellar reddening law in the Taurus dark clouds
Astrophysics and Space Science, 1982The interstellar reddening law in the Taurus dark clouds is investigated from visual, infrared, and ground based ultraviolet photometric observations of heavily reddened stars HD 29647, HDE 283701, and HDE 283812. The star HD 29647 located in the center of a very dense dark cloud Khavtassi 278 shows a reddening law which is anomalous in the wavelengths
V Straižys
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Interstellar chemistry of nitrogen hydrides in dark clouds [PDF]
Astronomy and Astrophysics, 2014 The aim of the present work is to perform a comprehensive analysis of the interstellar chemistry of nitrogen, focussing on the gas-phase formation of the smallest polyatomic species and in particular nitrogen hydrides. We present a new chemical network in which the kinetic rates of critical reactions have been updated based on recent experimental and ...
Alexandre Faure +2 more
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Interstellar extinction in the direction of the Merope dark cloud in pleiades
Astrophysics and Space Science, 1987The dependence of interstellar extinction on distance in the direction of the dark cloud south of Merope is determined using photoelectric photometry of 93 stars in the Vilnius photometric system. The cloud front edge is detected at 120–130 pc from the Sun and the distance of the Pleiades cluster is found to be 127 pc.
K Černis
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Young Stellar Objects and Dark Interstellar Clouds
Annual Review of Astronomy and Astrophysics, 1975This review synthesizes current observational knowledge concerning pre- main-sequence evolution and the interaction of pre-main-sequence stars with their dark cloud environment. Questions of current interest are raised and the direction of future fruitful research is discussed. (80 references) (BJG)
S E Strom, G L Grasdalen
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The 15 273 Å diffuse interstellar band in the dark cloud Barnard 68⋆ [PDF]
Astronomy and Astrophysics, 2017 High obscuration of background stars behind dark clouds precludes the detection of optical diffuse interstellar bands (DIBs) and hence our knowledge of DIB carriers in these environments. Taking advantage of the reduced obscuration of starlight in the near-infrared (NIR) we used one of the strongest NIR DIBs at 15 273 Å to probe the presence and ...
Rosine Lallement, Meriem Elyajouri
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Diffuse and Dark Clouds in the Interstellar Medium
1987This chapter deals with the IUE observations of interstellar matter in diffuse and dark clouds in the Milky Way and Magellanic Clouds. We will describe the data, its means of analysis, and the derived scientific knowledge about the structure, abundances, and physical state of the gas.
Klaas S. De Boer +2 more
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Supersonic waves of magnetization in dark interstellar molecular clouds
Journal of Experimental and Theoretical Physics Letters, 2000We suggest that supersonic linewidths inferred from recent measurements of magnetic fields toward the core position in dark interstellar molecular clouds may be due to transverse waves of magnetization propagating in a poorly ionized, magnetically ordered gas—dust medium composed of tiny ferromagnetic dusty grains suspended in a cold gaseous cloud of ...
J. Yang, S. I. Bastrukov
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Chemical Exchange Reactions and H2 Formation in Dark Interstellar Clouds
Nature, 1968Stecher and Williams1 have sought to explain the lack of 21 cm radiation in dark clouds on the basis of the formation of molecular H2. We wish to point out several serious deficiencies in their proposed production mechanism. Their chemical exchange process gives an H2 production rate1
P. M. SOLOMON, N. C. WICKRAMASINGHE
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The Chemistry of Diffuse and Dark Interstellar Clouds
1998Abstract Ever since the realization early this century that the space between the stars is not empty, the study of the physics and chemistry of the interstellar gas has played a prominent role in astrophysics (Eddington 1926). Most of the early work focused on absorption line observations of diffuse interstellar clouds, which do not ...
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Chemical processes in dark interstellar clouds – the effects of CNO depletion
Monthly Notices of the Royal Astronomical Society, 1991The effects of depletion on the elements C, N and O on the chemical composition of dark clouds are investigated, using both isothermal and isochoric cloud models. This work differs from previous approaches in that a much larger range of CNO depletions is considered.
Desforets, G.P. +2 more
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