148 citations · 1.4k across the 55 of their papers we have counts for
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An empirical recipe for inelastic hydrogen-atom collisions in non-LTE calculations
Rana Ezzeddine, Thibault Merle, Bertrand Plez +3
We investigate the role of hydrogen collisions in NLTE spectral line synthesis, and introduce a new general empirical recipe to determine inelastic charge transfer (CT) and bound-b…
Ultra metal-poor stars: Spectroscopic determination of stellar atmospheric parameters using iron Non-LTE line abundances
Rana Ezzeddine, Anna Frebel, Bertrand Plez
We present new ultra-metal-poor (UMP) stars parameters with [Fe/H]<-4.0 based on line-by-line non-local thermodynamic equilibrium (NLTE) abundances using an up-to-date iron model a…
Chemical Diversity in the Ultra-faint Dwarf Galaxy Tucana II
Alexander P. Ji, Anna Frebel, Rana Ezzeddine +1
We present the first detailed chemical abundance study of the ultra-faint dwarf galaxy Tucana II based on high-resolution Magellan/MIKE spectra of four red giant stars. The metalli…