Results 51 to 60 of about 206,370 (204)
Nebular Abundances of Nearby Southern Dwarf Galaxies [PDF]
The results of optical spectroscopy of H II regions in a sample of southern dwarf irregulars consisting of five dwarf galaxies in the Centaurus A group, four dwarfs in the Sculptor group, and eight additional dwarf galaxies are presented. Oxygen abundances are derived using the direct method where [O III]4363 is detected; otherwise, abundances are ...
arxiv +1 more source
Oxygen and nitrogen abundances in Virgo and field spirals [PDF]
The oxygen and nitrogen abundances in the HII regions of the nine Virgo spirals of the sample from Skillman et al (1996) and in nine field spiral galaxies are re-determined with the recently suggested P - method.
Alloin+79 more
core +2 more sources
The Gas-phase Mass–Metallicity Relation for Massive Galaxies at z ∼ 0.7 with the LEGA-C Survey
The massive end of the gas-phase mass–metallicity relation (MZR) is a sensitive probe of active galactic nuclei (AGN) feedback that is a crucial but highly uncertain component of galaxy evolution models.
Zach J. Lewis+14 more
doaj +1 more source
Chemical Abundances of the Leo II Dwarf Galaxy
We use previously-published moderate-resolution spectra in combination with stellar atmosphere models to derive the first measured chemical abundance ratios in the Leo II dSph galaxy.
Azzopardi+44 more
core +1 more source
We present the elemental abundances and ages of 19 massive quiescent galaxies at z ∼ 1.4 and z ∼ 2.1 from the Keck Heavy Metal Survey. The ultradeep LRIS and MOSFIRE spectra were modeled using a full-spectrum stellar population fitting code with variable
Aliza G. Beverage+13 more
doaj +1 more source
The Distribution of Alpha Elements in Andromeda Dwarf Galaxies [PDF]
We present alpha to iron abundance ratios for 226 individual red giant branch stars in nine dwarf galaxies of the Andromeda (M 31) satellite system. The abundances are measured from the combined signal of Mg, Si, Ca, and Ti lines in Keck/DEIMOS medium-resolution spectra.
arxiv +1 more source
The building up of the disk galaxy M33 and the evolution of the metallicity gradient
The evolution of radial gradients of metallicity in disk galaxies and its relation with the disk formation are not well understood. Theoretical models of galactic chemical evolution make contrasting predictions about the time evolution of metallicity ...
Aller+104 more
core +1 more source
Chemical Abundance Analysis of Tucana III, the Second $r$-process Enhanced Ultra-Faint Dwarf Galaxy [PDF]
We present a chemical abundance analysis of four additional confirmed member stars of Tucana III, a Milky Way satellite galaxy candidate in the process of being tidally disrupted as it is accreted by the Galaxy.
Bechtol, K.+60 more
core +3 more sources
Barium abundance in the central part of the dSph Fornax galaxy [PDF]
We revisited barium abundance in a sample of giant stars in the dwarf spheroidal Fornax galaxy. Non-local thermodynamic equilibrium (NLTE) synthesis was used to derive the barium abundance from two Ba II lines. Our new NLTE result for barium shows that in the range of metallicities from -1 to -0.5 the abundance of this element is almost the same as in ...
arxiv +1 more source
Nucleosynthesis: Stellar and Solar Abundances and Atomic Data [PDF]
Abundance observations indicate the presence of often surprisingly large amounts of neutron capture (i.e., s- and r-process) elements in old Galactic halo and globular cluster stars.
Collier, Jason+5 more
core +4 more sources