The Leiden Atomic and Molecular Database (LAMDA) collects spectroscopic information
and collisional rate coefficients for molecules, atoms, and ions of astrophysical and …

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 …

The CHIANTI spectral code consists of two parts: an atomic database and a suite of
computer programs in Python and IDL. Together, they allow the calculation of the optically …

Recently, Nicholls et al., inspired by in situ observations of solar system astrophysical
plasmas, suggested that the electrons in H ii regions are characterized by a κ-distribution of …

We present gas-phase elemental abundance ratios of thirteen local extremely metal-poor
galaxies (EMPGs), including our new Keck/LRIS spectroscopy determinations together with …

The derivation of abundances in gaseous nebulae ionized by massive stars using optical
collisionally excited emission lines is studied in this work, comparing the direct or T e …

Ultraviolet nebular emission lines are important for understanding the time evolution and
nucleosynthetic origins of their associated elements, but the underlying trends of their …

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 …

ABSTRACT The CHemical Abundances of Spirals (CHAOS) project leverages the combined
power of the Large Binocular Telescope (LBT) with the broad spectral range and sensitivity …

We present a reassessment of the radial abundance gradients of C, N, O, Ne, S, Cl, and Ar
in the Milky Way using deep spectra of 33 H ii regions gathered from the literature, covering …