Results 21 to 30 of about 36,750 (220)

Chemical Evolution of Some Selected Complex Organic Molecules in Low-mass Star-forming Regions

The Astrophysical Journal, 2023
The destiny of complex organic molecules (COMs) in star-forming regions is interlinked with various evolutionary phases. Therefore, identifying these species in diversified environments of identical star-forming regions would help to understand their ...
Bratati Bhat, Rumela Kar, Suman Kumar Mondal, Rana Ghosh, Prasanta Gorai, Takashi Shimonishi, Kei E. I. Tanaka, Kenji Furuya, Ankan Das   +8 more
doaj   +1 more source

Applications of Abundance Data and Requirements for Cosmochemical Modeling [PDF]

, 2001
Understanding the evolution of the universe from Big Bang to its present state requires an understanding of the evolution of the abundances of the elements and isotopes in galaxies, stars, the interstellar medium, the Sun and the heliosphere, planets and
Binns, W. R., Busemann, H., Chiappini, C., Gloeckler, G., Hoppe, P., Kirilova, D., Leske, R. A., Manuel, O. K., Mewaldt, R. A., Möbius, E., Wieler, R., Wiens, R. C., Wimmer-Schweingruber, R. F., Yanasak, N. E.   +13 more
core   +2 more sources

Inhomogeneous Enrichment of Radioactive Nuclei in the Galaxy: Deposition of Live 53Mn, 60Fe, 182Hf, and 244Pu into Deep-sea Archives. Surfing the Wave?

The Astrophysical Journal, 2023
While modeling the galactic chemical evolution (GCE) of stable elements provides insights to the formation history of the Galaxy and the relative contributions of nucleosynthesis sites, modeling the evolution of short-lived radioisotopes (SLRs) can ...
Benjamin Wehmeyer, Andrés Yagüe López, Benoit Côté, Maria K. Pető, Chiaki Kobayashi, Maria Lugaro   +5 more
doaj   +1 more source

Interstellar magnesium abundances

The Astrophysical Journal, 1984
An improved evaluation of the Mg II 1240 A doublet oscillator strength is used in conjunction with recently published Copernicus observations to derive accurate Mg II column densities toward 74 stars. These imply an average of 40 percent of interstellar magnesium is in the gaseous phase.
M. J. Murray, P. L. Dufton, A. Hibbert, D. G. York   +3 more
openaire   +1 more source

A JWST/NIRSpec Exploration of the Connection between Ionization Parameter, Electron Density, and Star-formation-rate Surface Density in z = 2.7–6.3 Galaxies

The Astrophysical Journal, 2023
We examine the factors responsible for the variation in the ionization parameter ( U ) of high-redshift star-forming galaxies based on medium-resolution JWST/NIRSpec observations obtained by the Cosmic Evolution Early Release Science survey.
Naveen A. Reddy, Michael W. Topping, Ryan L. Sanders, Alice E. Shapley, Gabriel Brammer   +4 more
doaj   +1 more source

Abundance of interstellar aluminum

The Astrophysical Journal, 1984
New observations of Al II 1670 A, the only line of the dominant ionization stage of interstellar aluminum detected to date, are presented. Observations of ionized silicon are used to define an empirical curve of growth from which aluminum depletions can be derived.
E. S. Barker, P. M. Lugger, E. J. Weiler, D. G. York   +3 more
openaire   +1 more source

Constraints on the nucleosynthesis of refractory nuclides in galactic cosmic rays [PDF]

, 2001
Abundances of the isotopes of the refractory elements Ca, Fe, Co, and Ni in the galactic cosmic-ray source are compared with corresponding abundances in solar-system matter.
Binns, W. R., Christian, E. R., Cummings, A. C., Davis, A. J., George, J. S., Hink, P. L., Israel, M. H., Leske, R. A., Mewaldt, R. A., Stone, E. C., von Rosenvinge, T. T., Wiedenbeck, M. E., Yanasak, N. E.   +12 more
core   +1 more source

Isotopic ratios and fractionation in the local Universe [PDF]

EPJ Web of Conferences, 2022
The knowledge of isotopic abundances is important in galaxy evolution studies because isotopes provide diagnostics for the chemical enrichment in galaxies over time.
Viti Serena
doaj   +1 more source

Cyanopolyyne Chemistry in the L1544 Prestellar Core: New Insights from GBT Observations

The Astrophysical Journal, 2023
We report a comprehensive study of the cyanopolyyne chemistry in the prototypical prestellar core L1544. Using the 100 m Robert C. Byrd Green Bank Telescope, we observe three emission lines of HC _3 N, nine lines of HC _5 N, five lines of HC _7 N, and ...
Eleonora Bianchi, Anthony Remijan, Claudio Codella, Cecilia Ceccarelli, Francois Lique, Silvia Spezzano, Nadia Balucani, Paola Caselli, Eric Herbst, Linda Podio, Charlotte Vastel, Brett McGuire   +11 more
doaj   +1 more source

Galactic Abundances: Report of Working Group 3 [PDF]

, 2001
We summarize the various methods and their limitations and strengths to derive galactic abundances from in-situ and remote-sensing measurements, both from ground-based observations and from instruments in space. Because galactic abundances evolve in time
Bothmer, V., Buclin, F., Christian, E. R., Cummings, A. C., Flückiger, E. O., George, J. S., Hofer, M. Y., Jones, F. C., Keller, J. W., Kirilova, D., Klecker, B., Kunow, H., Laming, M., Salerno, E., Sofia, U. J., Stone, E. C., Thielemann, F.-K., Tranquille, C., Wenzel, K.-P., Wiedenbeck, M. E.   +19 more
core   +1 more source