Results 31 to 40 of about 793,175 (240)

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

Abundance determinations in HII regions: model fitting versus Te-method [PDF]

, 2002
The discrepancy between the oxygen abundances in high-metallicity HII regions determined through the Te-method (and/or through the corresponding "strong lines - oxygen abundance" calibration) and that determined through the model fitting (and/or through ...
Alloin, Caplan, Cardelli, Castellanos, Deharveng, Dopita, Edmunds, Garnett, Kewley, Kinkel, Kobulnicky, L. S. Pilyugin, Malinie, McCall, McGaugh, Meyer, Pagel, Peimbert, Pilyugin, Pilyugin, Pilyugin, Pilyugin, Pilyugin, Sofia, Stasinska, Zaritsky   +25 more
core   +2 more sources

Galactic Cosmic Ray Origins and OB Associations: Evidence from SuperTIGER Observations of Elements $_{26}$Fe through $_{40}$Zr [PDF]

, 2016
We report abundances of elements from $_{26}$Fe to $_{40}$Zr in the cosmic radiation measured by the SuperTIGER (Trans-Iron Galactic Element Recorder) instrument during 55 days of exposure on a long-duration balloon flight over Antarctica.
Binns, W. R., Brandt, T. J., Hams, T., Israel, M. H., Labrador, A. W., Link, J. T., Mewaldt, R. A., Mitchell, J. W., Murphy, R. P., Rauch, B. F., Sakai, K., Sasaki, M., Stone, E. C., Waddington, C. J., Walsh, N. E., Ward, J. E., Wiedenbeck, M. E.   +16 more
core   +3 more sources

Observational Constraints on the Physical Properties of Interstellar Dust in the Post-Planck Era [PDF]

Astrophysical Journal, 2020
We present a synthesis of the astronomical observations constraining the wavelength-dependent extinction, emission, and polarization from interstellar dust from UV to microwave wavelengths on diffuse Galactic sight lines.
B. Hensley, B. Draine
semanticscholar   +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

Connecting the primordial and Galactic deuterium abundances [PDF]

, 2007
The deuterium abundances inferred from observations of the interstellar medium within 1-2 kpc of the Sun range over a factor of three and the corresponding oxygen abundances show an even larger dispersion.
Romano, Donatella, Steigman, Gary, Tosi, Monica   +2 more
core   +3 more sources

The carbon monoxide-rich interstellar comet 2I/Borisov [PDF]

, 2020
Interstellar comets offer direct samples of volatiles from distant protoplanetary disks. 2I/Borisov is the first notably active interstellar comet discovered in our Solar System 1 .
Dennis Bodewits, J. Noonan, Paul D. Feldman, Michele T. Bannister, D. Farnocchia, Walt Harris, Jenny Li, K. Mandt, J. Parker, Z. Xing, Z. Xing   +10 more
semanticscholar   +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

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