105 citations · 149 across the 12 of their papers we have counts for
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A method to derive self-consistent NLTE astrophysical parameters for 4 million high-resolution 4MOST stellar spectra in half a day with invertible neural networks
Victor F. Ksoll, Nicholas Storm, Maria Bergemann +5
Modern spectroscopic surveys obtain spectra for millions of stars. However, classical spectroscopic methods can often be computationally expensive, rendering them impractical for t…
Observational constraints on the origin of the elements. X. Combining NLTE and machine learning for chemical diagnostics of 4 million stars in the 4MIDABLE-HR survey
Nicholas Storm, Maria Bergemann, Tomasz Różański +9
We present the 4MOST-HR resolution Non-Local Thermal Equilibrium (NLTE) Payne artificial neural network (ANN), trained on new FGK spectra with 16 elements computed in NL…
Solar carbon abundance from 3D non-LTE modelling of the diagnostic lines of the CH molecule
Richard Hoppe, Maria Bergemann, Philipp Eitner +5
The spectral lines of the CH molecule are a key carbon (C) abundance diagnostic in FGKM-type stars. These lines are detectable in metal-rich and, in contrast to atomic C lines, als…
3D Non-LTE radiation transfer: theory and applications to stars, exoplanets, and kilonovae
Maria Bergemann, Richard Hoppe
Most of the physical information about astrophysical objects is obtained via the analysis of their electromagnetic spectra. Observed data coupled with radiation transfer models in…
M3DIS -- A grid of 3D radiation-hydrodynamics stellar atmosphere models for stellar surveys. II. Carbon-enhanced metal-poor stars
Philipp Eitner, Maria Bergemann, Richard Hoppe +6
Understanding the origin and evolution of carbon-enhanced metal-poor (CEMP) stars is key to tracing the Galaxy's early chemical enrichment. We investigate how realistic 3D radiatio…
Observational constraints on the origin of the elements. IX. 3D NLTE abundances of metals in the context of Galactic Chemical Evolution Models and 4MOST
Nicholas Storm, Maria Bergemann, Philipp Eitner +8
Historically, various methods have been employed to understand the origin of the elements, including observations of elemental abundances which have been compared to Galactic Chemi…
NLTE abundances of Eu for a sample of metal-poor stars in the Galactic Halo and Metal-poor Disk with 1D and <3D> models
Yanjun Guo, Nicholas Storm, Maria Bergemann +6
Accurate measurements of europium abundances in cool stars are essential for an enhanced understanding of the r-process mechanisms. We measure the abundance of Eu in solar spectra…
M3DIS -- A grid of 3D radiation-hydrodynamics stellar atmosphere models for stellar surveys
Philipp Eitner, Maria Bergemann, Richard Hoppe +3
Large-scale stellar surveys, such as SDSS-V, 4MOST, WEAVE, and PLATO, require accurate atmospheric models and synthetic spectra of stars for accurate analyses of fundamental stella…
3D NLTE modelling of Y and Eu. Centre-to-limb variation and solar abundances
N. Storm, P. S. Barklem, S. A. Yakovleva +6
Context. Abundances of s- and r-process elements in Sun-like stars constrain nucleosynthesis in extreme astrophysical events, such as compact binary mergers and explosions of highl…
The GALAH Survey: Non-LTE departure coefficients for large spectroscopic surveys
A. M. Amarsi, K. Lind, Y. Osorio +23
Massive sets of stellar spectroscopic observations are rapidly becoming available and these can be used to determine the chemical composition and evolution of the Galaxy with unpre…