Results 31 to 40 of about 612,500 (304)
Ruthenium and hafnium abundances in giant and dwarf barium stars
, 2007 We present abundances for Ru and Hf, compare them to abundances of other heavy elements, and discuss the problems found in determining Ru and Hf abundances with laboratory gf-values in the spectra of barium stars.
Allen +31 more
core +1 more source
Julius-Kühn-Archiv, 2013 Agricultural landscapes have crucial functions for biodiversity conservation. Contrary to the goals of biodiversity protection the habitat functions and the biological diversity are deteriorating, especially in arable areas.
Hoffmann, Jörg +5 more
doaj +1 more source
Understanding the Chemical Evolution of Blue Edge-on Low Surface Brightness Galaxies
The Astrophysical Journal, 2023 We present a sample of 330 blue edge-on low surface brightness galaxies (ELSBGs). To understand the chemical evolution of ELSBGs, we derived the gas-phase abundance and the [ α /Fe] ratio.
Tian-wen Cao +6 more
doaj +1 more source
Chemical Abundances in AGN Environment: X-Ray/UV Campaign on the MRK 279 Outflow [PDF]
, 2006 We present the first reliable determination of chemical abundances in an AGN outflow. The abundances are extracted from the deep and simultaneous FUSE and HST/STIS observations of Mrk 279.
Ari Laor +15 more
core +3 more sources
Direct D-atom Incorporation in Radicals: An Overlooked Pathway for Deuterium Fractionation
The Astrophysical Journal, 2023 Direct D-H exchange in radicals is investigated in a quasi-uniform flow employing chirped-pulse millimeter-wave spectroscopy. Inspired by the H-atom catalyzed isomerization of C _3 H _2 reported in our previous study, D-atom reactions with the propargyl (
Nureshan Dias +4 more
doaj +1 more source
Optical and mid-infrared neon abundance determinations in star-forming regions [PDF]
, 2013 We employed observational spectroscopic data of star-forming regions compiled from the literature and photoionization models to analyse the neon ionic abundances obtained using both optical and mid-infrared emission-lines.
Cardaci, Monica V. +8 more
core +4 more sources
The Astrophysical Journal, 2023 Stellar streams in the Galactic halo are useful probes of the assembly of galaxies like the Milky Way. Many tidal stellar streams that have been found in recent years are accompanied by a known progenitor globular cluster or dwarf galaxy.
Keith Hawkins +10 more
doaj +1 more source
Atomic diffusion in the atmosphere of Feige 86
Open Astronomy, 2017 We have revisited the ultraviolet and optical spectra of the blue horizontal branch star Feige 86. The new analysis finds the star cooler and more compact than previously determined. The IUE spectrum of Feige 86 holds numerous unidentified spectral lines
Németh Péter
doaj +1 more source
Chemical abundances of LINER galaxies – nitrogen abundance estimations
Monthly Notices of the Royal Astronomical SocietyABSTRACT In this work, we investigated the nitrogen and oxygen abundances in a sample of galaxies with Low Ionization Nuclear Emission Regions (LINERs) in their nucleus. Optical spectroscopic data (3600 – 10 000 Å) of 40 LINERs from the Mapping Nearby Galaxies (MaNGAs) survey were considered.
C B Oliveira +7 more
openaire +3 more sources
Results of 40-year Studies of the X-Ray Binary Cyg X-1 = V1357 Cyg
Open Astronomy, 2016 This paper reviews the results of our 40-year studies of Cyg X-1 using various methods and observational data: mainly optical photometric, spectroscopic, and polarimetric ones, with X-ray data also considered.
Karitskaya E. A.
doaj +1 more source