Results 61 to 70 of about 889,569 (256)

Boundary conditions for the paleoenvironment: Chemical and physical processes in the pre-solar nebula [PDF]

Detailed study of the first interstellar hydrocarbon ring, cyclopropenylidene (C3H2), is continuing. The singly deuterated isotope of this molecule, C3HD, was observed in several cold interstellar clouds.
Irvine, William M., Schloerb, F. Peter
core   +4 more sources

Kinematics of H I Envelopes Associated with Molecular Clouds

The Astronomical Journal
We investigate the evolution of molecular clouds through the kinematics of their atomic hydrogen (H I ) envelopes, using ^12 CO and 21 cm emission to trace the molecular and atomic gas, respectively.
Thummim Mekuria, Nia Imara
doaj   +1 more source

FORMATION OF SMALL-SCALE STRUCTURES IN THEINTERSTELLAR MEDIUM

Odessa Astronomical Publications, 2008
We consider formation of small scale structures in the process of interstellar cloud destruction by shock waves. We calculate statistical properties of HI column densities, optical depth and brightness temperature in 21 cm line.
E. E. Matvienko, E. O. Vasiliev, Yu. A. Shchekinov   +2 more
doaj   +1 more source

High-resolution Observations of H i in the IC 63 Reflection Nebula

The Astronomical Journal, 2023
Photodissociation regions (PDRs), where the (far-)ultraviolet light from hot young stars interact with the gas in surrounding molecular clouds, provide laboratories for understanding the nature and role of feedback by star formation on the interstellar ...
Lars Bonne, B-G Andersson, Robert Minchin, Archana Soam, Joshua Yaldaei, Kristin Kulas, Janik Karoly, Lewis B. G. Knee, Siddharth Kumar, Nirupam Roy   +9 more
doaj   +1 more source

Physical conditions in CaFe interstellar clouds

, 2007
Interstellar clouds that exhibit strong Ca I and Fe I lines were called CaFe clouds. The ionisation equilibrium equations were used to model the column densities of Ca II, Ca I, K I, Na I, Fe I and Ti II in CaFe clouds.
Badnell, Bagnulo, Black, Bondar, Danks, de Boer, Federman, Gnacinski, Gnacinski, Grevesse, Keenan, Landini, Landini, M. Krogulec, Mazzotta, Morton, P. Gnaciński, Piskunov, Shull, Voronov, Weingartner   +20 more
core   +1 more source

Prebiotic Organic Chemistry of Diketopiperazines

Asian Journal of Organic Chemistry, Volume 15, Issue 4, April 2026.
Diketopiperazines (DKPs) are considered essential in many life forms, but their prebiotic importance has not been fully understood. This review aims to discuss prebiotic organic chemistry for experimentally and computationally simulated reactions involving DKPs. ABSTRACT Even though the significance of amino acids and polypeptides is well recognized in
Jun Ohata
wiley   +1 more source

The H2 Glow of a Quiescent Molecular Cloud Observed with JWST

The Astrophysical Journal Letters
We report JWST MIRI/MRS observations of the H _2 S (1) 17.04 μ m transition in two regions in the boundary of the Taurus molecular cloud. The two regions, denoted “Edge” (near the relatively sharp boundary of the ^13 CO J  = 1 → 0 emission) and “Peak ...
Paul F. Goldsmith, Shengzhe Wang, Xin Wang, Raphael Skalidis, Gary A. Fuller, Di Li, Chao-Wei Tsai, Lile Wang, Donghui Quan   +8 more
doaj   +1 more source

Physical Properties of Giant Molecular Clouds in the Large Magellanic Cloud [PDF]

, 2010
The Magellanic Mopra Assessment (MAGMA) is a high angular resolution CO mapping survey of giant molecular clouds (GMCs) in the Large and Small Magellanic Clouds using the Mopra Telescope. Here we report on the basic physical properties of 125 GMCs in the
A. Hughes, A. Kawamura, Akritas, Alves, Babu, Ballesteros-Paredes, Ballesteros-Paredes, Bergin, Bernard, Blanc, Blitz, Blitz, Blitz, Blitz, Bolatto, Bolatto, Boulanger, Chieze, Chin, Cole, D. Paradis, Dickey, Dickman, Dobashi, E. Muller, Elmegreen, Federman, Fleck, Fukui, Garay, Gaustad, Hartmann, Heikkilä, Heyer, Heyer, Heyer, Israel, Israel, Israel, Israel, J. L. Pineda, J. Ott, J.-P. Bernard, Johansson, Kawamura, Kelly, Kim, Kim, Krumholz, Krumholz, Kutner, L. Staveley-Smith, Ladd, Larson, Larson, Lequeux, Leroy, Leroy, Leroy, Luks, M. Meixner, Mac Low, MacLaren, Maloney, Marx-Zimmer, McKee, Meixner, Minamidani, Miville-Deschênes, Mizuno, Moorey, Muller, N. Mizuno, Nikolaev, Nikolaev, Ott, Paradis, Pineda, Pineda, Press, Rosolowsky, Rosolowsky, Rosolowsky, Rosolowsky, S. Kim, S. Maddison, Sault, Skrutskie, Solomon, Sorai, Staveley-Smith, Strong, T. Onishi, T. Wong, Tasker, Tremaine, Van Der Marel, Van Dishoeck, W. T. Reach, Walter, Williams, Williams, Wilson, Wolfire, Wong, Wong, Y. Fukui, Y. Mizuno, Yang, Zhao   +109 more
core   +3 more sources

Composite Single‐Reference and Explicitly Correlated Multireference Calculations on the Mechanism of Pyrrole Pyrolysis

Journal of Physical Organic Chemistry, Volume 39, Issue 4, April 2026.
New calculations have been applied to the pyrolysis of pyrrole under shock‐tube conditions and to the radical‐radical reaction between allyl and •CN at low temperature and pressure, using the same mechanistic scheme for both. ABSTRACT The pyrolysis of pyrrole has previously been studied in shock‐tube experiments and in jet‐stirred reactors. The results
Barry K. Carpenter
wiley   +1 more source

Strength Ratios of Diffuse Interstellar Bands in Slightly Reddened Objects

Universe
The disk of the Milky Way fills the interstellar medium in the form of discrete clouds, many (∼30) light-years across. The average density of this medium is 1 hydrogen atom per cm3 (Oort limit), in the clouds—several dozen atoms, and between the clouds ...
Jacek Krełowski, Arkadii Bondar
doaj   +1 more source