H ii regions are ionized nebulae surrounding massive stars. They exhibit a wealth of
emission lines that form the basis for estimation of chemical composition. Heavy elements …

We present a first study based on the analysis of the DEep Spectra of Ionized REgions Data
base (DESIRED). This is a compilation of 190 high signal-to-noise ratio optical spectra of …

We present a tutorial on the determination of the physical conditions and chemical
abundances in gaseous nebulae. We also include a brief review of recent results on the …

We provide new ionization correction factors (ICFs) for carbon, nitrogen, neon, sulfur,
chlorine, and argon in giant H ii regions. The ICFs were computed using the most …

Almost all chemical elements have been made by nucleosynthetic reactions in various kind
of stars and have been accumulated along our cosmic history. Among those elements, the …

Context. In stars, metallicity is usually traced using Fe, while in nebulae, O serves as the
preferred proxy. Both elements have different nucleosynthetic origins and are not directly …

We present the analysis of physical conditions, chemical composition, and kinematic
properties of two bow shocks–HH 529 II and HH 529 III–of the fully photoionized Herbig …

We here present the results from a detailed analysis of nebular abundances of commonly
observed ions in the collisional ring galaxy Cartwheel using the Very Large Telescope (VLT) …

High-resolution spectra of singly ionized nickel (Ni ii) have been recorded using Fourier
transform spectroscopy in the region 143–5555 nm (1800–70,000 cm− 1) with continuous …

We present the analysis of archival Very Large Telescope Multi-Unit Spectroscopic Explorer
observations of 179 H ii regions in the star-forming double-ring collisional galaxy AM 0644 …