626 citations · 4.9k across the 107 of their papers we have counts for
107 papers
Detailed Abundance Determination of Metal-Poor Stars with X-Shooter II. - Chemically Disentangling the Halo, Disk and GSE
Benjamin D. C. Lowe, Luca Casagrande, Thomas Nordlander +2
We present a detailed chemical analysis of seven extremely metal-poor (EMP) star candidates observed with X-Shooter, combining them with 16 EMP candidates from Paper I. We measured…
The complex stellar system M 22: constraining the chemical enrichment from AGB stars using magnesium isotope ratios
M. McKenzie, D. Yong, A. I. Karakas +8
The complex star cluster M 22 (NGC 6656) provides a unique opportunity for studying slow neutron-capture (s-process) nucleosynthesis at low metallicity due to its two stellar group…
The impact of stellar binaries and star cluster dynamics on pair-instability supernovae
Francesco Gabrielli, Cristiano Ugolini, Lavinia Paiella +12
Pair-instability supernovae (PISNe) are among the most luminous transients in the Universe. However, they have never been confidently observed. Solving this puzzle would have key i…
The GALAH Survey: Neutron-Capture Elemental Abundances for 350,000 Gaia-RVS spectra and the Chemodynamics of Accreted Structures
Pradosh Barun Das, Daniel B. Zucker, Aldo Mura-Guzmán +15
We present a comprehensive data-driven spectroscopic analysis of 357,415 red giant stars using Gaia DR3 Radial Velocity Spectrometer (RVS) spectra (8460-8700 A; ),…
Detailed Abundance Determination of Metal-Poor Stars with X-Shooter I. Unusual Chemistry in Halo Stars
Benjamin D. C. Lowe, Thomas Nordlander, Luca Casagrande +5
We present a detailed chemical analysis study of 16 candidate metal-poor stars, previously identified with 2dF + AAOmega, using X-Shooter spectra and the Korg 1D local thermodynami…
Optical spectroscopic signatures of the red giant evolutionary state
Ella Xi Wang, Melissa Ness, Thomas Nordlander +17
Modern spectroscopic surveys output large data volumes. Theoretical models provide a means to transform the information encoded in these data to measurements of physical stellar pr…
Abundance Measurements of the Metal-poor M subdwarf LHS 174 Using High-resolution Optical Spectroscopy
Neda Hejazi, Sebastien Lepine, Thomas Nordlander +3
Metal-poor M subdwarfs are among the oldest stellar populations and carry valuable information about the chemical enrichment history of the Milky Way. The measurements of chemical…
A Main Sequence CH-star in the globular cluster M55 (NGC 6809)
G. S. Da Costa, T. Nordlander
Spectra have been obtained with multi-fibre instrument 2dF on the Anglo-Australian Telescope of 89 candidate main sequence stars in the globular cluster M55 (NGC 6809). Radial velo…
C3PO IV: co-natal stars depleted in refractories are magnetically more active -- possible imprints of planets
Jie Yu, Yuan-Sen Ting, Luca Casagrande +14
Chemical abundance anomalies in twin stars have recently been considered tell-tale signs of interactions between stars and planets. While such signals are prevalent, their nature r…
The Rise of the Milky Way Disk through EMP Stars
B. Lowe, T. Nordlander, L. Casagrande +6
We present a chemo-dynamical study conducted with 2dFAAOmega of Gaia DR3 non-variable candidate metal-poor stars that lie in the direction of the Galactic plane. Our…
The GALAH survey: Improving chemical abundances using star clusters
Janez Kos, Sven Buder, Kevin L. Beeson +18
Large spectroscopic surveys aim to consistently compute stellar parameters of very diverse stars while minimizing systematic errors. We explore the use of stellar clusters as bench…
A simple model for spectroscopic analyses of active stars
T. Nordlander, M. Baratella, L. Spina +1
Spectroscopic analyses of young late-type stars suffer from systematic inaccuracies, typically under-estimating metallicities but over-estimating abundances of certain elements inc…
Starkiller: subtracting stars and other sources from IFU spectroscopic data through forward modeling
Ryan Ridden-Harper, Michele T. Bannister, Sophie E. Deam +1
We present starkiller, an open-source Python package for forward-modeling flux retrieval from integral field unit spectrograph (IFU) datacubes. Starkiller simultaneously provides s…
The GALAH Survey: Stellar parameters and abundances for 800,000 Gaia RVS spectra using GALAH DR4 and The Cannon
Pradosh Barun Das, Daniel B. Zucker, Gayandhi M. De Silva +15
Analysing stellar parameters and abundances from nearly one million Gaia Data Release 3 (DR3) Radial Velocity Spectrometer (RVS) spectra poses challenges due to the limited spectra…
The GALAH Survey: Data Release 4
S. Buder, J. Kos, E. X. Wang +36
The stars of the Milky Way carry the chemical history of our Galaxy in their atmospheres as they journey through its vast expanse. Like barcodes, we can extract the chemical finger…
High-resolution Elemental Abundance Measurements of Cool JWST Planet Hosts Using AutoSpecFit: An Application to the Sub-Neptune K2-18b's Host M dwarf
Neda Hejazi, Ian J. M. Crossfield, Diogo Souto +9
We present an in-depth, high-resolution spectroscopic analysis of the M dwarf K2-18 that hosts a sub-Neptune exoplanet in its habitable zone. We show our technique to accurately no…
The Wide-field Spectroscopic Telescope (WST) Science White Paper
Vincenzo Mainieri, Richard I. Anderson, Jarle Brinchmann +214
The Wide-field Spectroscopic Telescope (WST) is proposed as a new facility dedicated to the efficient delivery of spectroscopic surveys. This white paper summarises the initial con…
Metallicities for more than 10 million stars derived from Gaia BP/RP spectra
T. Xylakis-Dornbusch, N. Christlieb, T. T. Hansen +3
Context. The third Gaia Data Release, which includes BP/RP spectra for 219 million sources, has opened a new window in the exploration of the chemical history and evolution of the…
Cool and Data-Driven: An Exploration of Optical Cool Dwarf Chemistry with Both Data-Driven and Physical Models
Adam D. Rains, Thomas Nordlander, Stephanie Monty +6
Detailed chemical studies of F/G/K -- or Solar-type -- stars have long been routine in stellar astrophysics, enabling studies in both Galactic chemodynamics, and exoplanet demograp…
3D NLTE Lithium abundances for late-type stars in GALAH DR3
Ella Xi Wang, Thomas Nordlander, Sven Buder +7
Lithium's susceptibility to burning in stellar interiors makes it an invaluable tracer for delineating the evolutionary pathways of stars, offering insights into the processes gove…
High-resolution spectroscopic study of extremely metal-poor stars in the Large Magellanic Cloud
W. S. Oh, T. Nordlander, G. S. Da Costa +2
We present detailed abundance results based on UVES high dispersion spectra for 7 very and extremely metal-poor stars in the Large Magellanic Cloud. We confirm that all 7 stars, tw…
Atomic Diffusion and Mixing in Old Stars VIII: Chemical abundance variations in the globular cluster M4 (NGC 6121)
T. Nordlander, P. Gruyters, O. Richard +1
Variations in chemical abundances with evolutionary phase have been identified among stars in globular and open clusters with a wide range of metallicities. In the metal-poor clust…
HRMOS White Paper: Science Motivation
Laura Magrini, Thomas Bensby, Anna Brucalassi +52
The High-Resolution Multi-Object Spectrograph (HRMOS) is a facility instrument that we plan to propose for the Very Large Telescope (VLT) of the European Southern Observatory (ESO)…
3D Stagger model atmospheres with FreeEOS I. Exploring the impact of microphysics on the Sun
Yixiao Zhou, Anish M. Amarsi, Victor Aguirre Børsen-Koch +3
Three-dimensional radiation-hydrodynamics (3D RHD) simulations of stellar surface convection provide valuable insights into many problems in solar and stellar physics. However, alm…