Results 61 to 70 of about 35,391 (195)

Photochemistry of interstellar molecules [PDF]

The photochemistry of two diatomic and eight polyatomic molecules is discussed quantitatively. For an interstellar molecule, the lifetime against photodecomposition depends upon the absorption cross section, the quantum yield or probability of ...
Stief, L. J.
core   +1 more source

The 15N-enrichment in dark clouds and Solar System objects

, 2013
The line intensities of the fundamental rotational transitions of H13CN and HC15N were observed towards two prestellar cores, L183 and L1544, and lead to molecular isotopic ratios 140 6 14N/15N 6 250 and 140 6 14N/15N 6 360, respectively.
Bonal, Lydie, Faure, Alexandre, Hily-Blant, Pierre, Quirico, Eric   +3 more
core   +2 more sources

Quantum mechanical modeling of interstellar molecules on cosmic dusts: H₂O, NH₃, and CO₂. [PDF]

Front Chem, 2022
Li F, Quan D, Zhang X, Li X, Esimbek J.
europepmc   +1 more source

Chemistry in Dense Molecular Clouds: Theory and Observational Constraints [PDF]

, 1988
For the most part, gas phase models of the chemistry of dense molecular clouds predict the abundances of simple species rather well. However, for larger molecules and even for small systems rich in carbon these models often fail spectacularly.
Blake, Geoffrey A.
core  

Effects of H2 coating of grains on depletion of molecular species

, 2012
Physical conditions in dense and cold regions of interstellar clouds favour the formation of ice mantles on the surfaces of interstellar grains. It is predicted that most of the gaseous species heavier than H2 or He will adsorb onto the grains and will ...
Hasegawa, Tatsuhiko I., Morata, Oscar
core   +1 more source

Determining the Methanol Deuteration in the Disk Around V883 Orionis with Laboratory Measured Spectroscopy

The Astronomical Journal
Deuterium fractionation, as studied through mono-deuterated methanol, is frequently used as a diagnostic tool to trace the physical conditions and chemical evolution of interstellar sources. This study investigates methanol deuteration in the disk around
Shaoshan Zeng, Jae-Hong Jeong, Takahiro Oyama, Jeong-Eun Lee, Yao-Lun Yang, Nami Sakai   +5 more
doaj   +1 more source

Interstellar grain chemistry and organic molecules [PDF]

The detection of prominant infrared absorption bands at 3250, 2170, 2138, 1670 and 1470 cm(-1) (3.08, 4.61, 4.677, 5.99 and 6.80 micron m) associated with molecular clouds show that mixed molecular (icy) grain mantles are an important component of the ...
Allamandola, L. J., Sandford, S. A.
core   +1 more source

The formation of H_2 and HD with the master equation approach

, 2005
The formation of H2 and HD molecules on interstellar dust grains is studied using rate equation and master equation models. Rate equations are used in the analysis of laboratory experiments which examine the formation of molecular hydrogen on ...
Biham, Ofer, Lipshtat, Azi, Perets, Hagai B.   +2 more
core   +1 more source

ALMA Reveals Diverse Dust-to-gas Mass Ratios and Quenching Modes in Old Quiescent Galaxies

The Astrophysical Journal Letters
Recent discoveries of dust and molecular gas in quiescent galaxies (QGs) up to z ∼ 4 challenge the long-standing view that the interstellar medium depletes rapidly once star formation ceases, raising key questions of whether dust and gas coevolve in QGs,
G. Lorenzon, D. Donevski, A. W. S. Man, M. Romano, K. E. Whitaker, S. Belli, D. Liu, M. M. Lee, D. Narayanan, A. Long, I. Shivaei, A. Nanni, K. Lisiecki, P. Sawant, G. Rodighiero, I. Damjanov, Junais, R. Davé, C. Pappalardo, C. Lovell, M. Hamed   +20 more
doaj   +1 more source

Regarding the Detection of Interstellar C4 and C5 Molecules

The Astrophysical Journal
Analysis of very high signal-to-noise ratio (S/N) spectra of reddened stars allowed us to determine an upper limit (UL) of the column density N (C _4 ).
G. A. Galazutdinov, E. I. Kazanina, J. Krełowski   +2 more
doaj   +1 more source