Results 91 to 100 of about 63,480 (217)

Observation of interstellar lithium in the low-metallicity Small Magellanic Cloud

, 2012
The primordial abundances of light elements produced in the standard theory of Big Bang nucleosynthesis (BBN) depend only on the cosmic ratio of baryons to photons, a quantity inferred from observations of the microwave background.
AJ Korn, BD Fields, Brian D. Fields, D Romano, DC Knauth, DE Welty, DE Welty, DE Welty, DL Lambert, F Iocco, G Steigman, G Steigman, Grant J. Mathews, H Dekker, J Dunkley, J Meléndez, J. Christopher Howk, JC Weingartner, K Jedamzik, L Sbordone, M Asplund, M Pospelov, M Spite, N Prantzos, Nicolas Lehner, NLJ Cox, RH Cyburt, S Kawanomoto, SIB Cartledge, T Prodanović, TK Suzuki   +30 more
core   +1 more source

Adsorption of Helium on Cationic or Anionic Tetracene and Pentacene

Small Structures, Volume 7, Issue 1, January 2026.
How does the arrangement of helium atoms that are adsorbed on tetracene or pentacene ions change with increasing coverage? When does the adsorption layer change from 1D to 2D, and to 3D? Is the transition abrupt? Are the helium atoms localized? Is the arrangement the same for cations and anions? What changes as the acene grows in length?
Miriam Kappe, Florent Calvo, Rasif William, Bilal Rasul, Masoomeh Mahmoodi‐Darian, Paul Scheier, Olof Echt   +6 more
wiley   +1 more source

The density distribution and 58.4 nm radiation intensity of interstellar helium in the heliosphere: a model simulation

Earth and Planetary Physics
Research on the interstellar medium and its interaction with the solar system constitutes a significant topic in planetary physics. As the Sun traverses the local interstellar cloud, interstellar neutrals penetrate the heliosphere, forming the ...
JiaLing Lyu, ChongJing Yuan, Fei He, BeiLi Ying   +3 more
doaj   +1 more source

Herschel/HIFI discovery of interstellar chloronium (H_2Cl^+) [PDF]

, 2010
We report the first detection of chloronium, H_2Cl^+, in the interstellar medium, using the HIFI instrument aboard the Herschel Space Observatory. The 2_(12)−1_(01) lines of ortho-H^(35)_2 Cl^+ and ortho-H^(37)_2 Cl^+ are detected in absorption towards ...
Bell, T. A., Blake, G. A., Boogert, A., Emprechtinger, M., Lis, D. C., Lord, S. D., Phillips, T. G., Zmuidzinas, J.   +7 more
core  

The chemistry of fluorine-bearing molecules in diffuse and dense interstellar gas clouds

, 2005
We present a theoretical investigation of the chemistry of fluorine-bearing molecules in diffuse and dense interstellar gas clouds. The chemistry of interstellar fluorine is qualitatively different from that of any other element, because - unlike the ...
Neufeld, David A., Schilke, Peter, Wolfire, Mark G.   +2 more
core   +1 more source

Ne and Fe Abundances in the Interstellar Medium: Archival Study of Fe-L and Ne-K Edges in Chandra and XMM-Newton

The Astrophysical Journal
The abundance of elements in the interstellar medium is a key facet for many fields of astrophysical study. In the soft X-ray spectra, absorption by interstellar gas can result in deep absorption features that affect continuum measurements. In this paper,
D. L. Moutard, L. R. Corrales, I. Psaradaki, E. Temple, M. Shi   +4 more
doaj   +1 more source

Strong and selective isotope effect in the vacuum ultraviolet photodissociation branching ratios of carbon monoxide

Nature Communications, 2019
Carbon monoxide is the main C and O reservoir in interstellar media, where it undergoes photochemistry. The authors show that isotopic substitution affects not only its absorption. spectrum and photodissociation rates but also the branching ratio, key to
Pan Jiang, Xiaoping Chi, Qihe Zhu, Min Cheng, Hong Gao   +4 more
doaj   +1 more source

The Local Group L-band Survey: The First Measurements of Localized Cold Neutral Medium Properties in the Low-metallicity Dwarf Galaxy NGC 6822

The Astrophysical Journal
Measuring the properties of the cold neutral medium (CNM) in low-metallicity galaxies provides insights into heating and cooling mechanisms in early Universe-like environments.
Nickolas M. Pingel, Hongxing Chen, Snežana Stanimirović, Eric W. Koch, Adam K. Leroy, Erik Rosolowsky, Chang-Goo Kim, Julianne J. Dalcanton, Fabian Walter, Michael P. Busch, Ryan Chown, Jennifer Donovan Meyer, Cosima Eibensteiner, Deidre A. Hunter, Sumit K. Sarbadhicary, Elizabeth Tarantino, Vicente Villanueva, Thomas G. Williams   +17 more
doaj   +1 more source

Modeling galactic extinction

Atti della Accademia Peloritana dei Pericolanti : Classe di Scienze Fisiche, Matematiche e Naturali, 2011
We present a model for interstellar extinction dust, in which we assume a bimodal distribution of extinction carriers, a dispersion of core-mantle grains, supplemented by a collection of PAHs in free molecular form.
C. Cecchi-Pestellini, G. Mulas, S. Casu, M.A. Iati', R. Saija, A. Cacciola, F. Borghese, P. Denti   +7 more
doaj   +1 more source

H i Kinematics and the E(B − V)/N(H i) Ratio

The Astrophysical Journal
The λ 21 cm H i emission that is used to trace the gas-to-dust ratio at high Galactic latitudes has contributions from material beyond the Milky Way disk, with uncertain and likely subsolar metallicity and dust content.
Harvey Liszt
doaj   +1 more source