Publications (24)
Critical accretion rates for rapidly growing massive Population III stars
Devesh Nandal, John A. Regan, Tyrone E. Woods +3
Efforts to understand the origin and growth of massive black holes observed in the early Universe have spurred a strong interest in the evolution and fate of rapidly-accreting prim…
Modules for Experiments in Stellar Astrophysics (MESA): Time-Dependent Convection, Energy Conservation, Automatic Differentiation, and Infrastructure
Adam S. Jermyn, Evan B. Bauer, Josiah Schwab +19
We update the capabilities of the open-knowledge software instrument Modules for Experiments in Stellar Astrophysics (MESA). The new auto_diff module implements automatic different…
Fluorine production in He-burning regions of massive stars during cosmic history
Sophie Tsiatsiou, Georges Meynet, Eoin Farrell +11
The origin of fluorine is still a debated question. AGB stars synthesise this element and likely contribute significantly to its synthesis in the present-day Universe. However, it…
A method for non-linear inversion of the stellar structure applied to gravity-mode pulsators
Eoin Farrell, Gaël Buldgen, Georges Meynet +3
We present a method for a non-linear asteroseismic inversion suitable for gravity-mode pulsators and apply it to slowly pulsating B-type (SPB) stars. Our inversion method is based…
Applying sparse autoencoders to unlearn knowledge in language models
Eoin Farrell, Yeu-Tong Lau, Arthur Conmy
We investigate whether sparse autoencoders (SAEs) can be used to remove knowledge from language models. We use the biology subset of the Weapons of Mass Destruction Proxy dataset a…
Rapidly rotating Population III stellar models as a source of primary nitrogen
Sophie Tsiatsiou, Yves Sibony, Devesh Nandal +12
The first stars might have been fast rotators. This would have important consequences for their radiative, mechanical and chemical feedback. We discuss the impact of fast initial r…
SNAPSHOT: Connections between Internal and Surface Properties of Massive Stars
Eoin Farrell, Jose Groh, Georges Meynet +3
We introduce SNAPSHOT, a technique to systematically compute stellar structure models in hydrostatic and thermal equilibrium based on 3 structural properties - core mass $M_{\rm co…
Impact of binary interaction on the evolution of blue supergiants
Eoin Farrell, Jose Groh, Georges Meynet +5
A large fraction of massive stars evolve in interacting binary systems, which dramatically modifies the outcome of stellar evolution. We investigated the properties of blue supergi…
Grids of stellar models with rotation VI: Models from 0.8 to 120 at a metallicity Z = 0.006
Patrick Eggenberger, Sylvia Ekström, Cyril Georgy +14
Context: Grids of stellar models, computed with the same physical ingredients, allow one to study the impact of a given physics on a broad range of initial conditions and are a key…
Grids of stellar models with rotation: V. Models from 1.7 to 120 Msun at zero metallicity
Laura J. Murphy, Jose H. Groh, Sylvia Ekstrom +10
Understanding the nature of the first stars is key to understanding the early universe. With new facilities such as JWST we may soon have the first observations of the earliest ste…
Toward a Comprehensive Grid of Cepheid Models with MESA I. Uncertainties of the Evolutionary Tracks of Intermediate-Mass Stars
Oliwia ZióÅkowska, RadosÅaw Smolec, Anne Thoul +3
Helium-burning stars, in particular Cepheids, are especially difficult to model, as the choice of free parameters can greatly impact the shape of the blue loops - the part of the e…
Grids of stellar models with rotation VII: Models from 0.8 to 300 M at super-solar metallicity (Z = 0.020)
Norhasliza Yusof, Raphael Hirschi, Patrick Eggenberger +11
We present a grid of stellar models at super-solar metallicity (Z = 0.020) extending the previous grids of Geneva models at solar and sub-solar metallicities. A metallicity of Z =…
Ionizing photon production of Population III stars: effects of rotation, convection, and initial mass function
Laura J. Murphy, Jose H. Groh, Eoin Farrell +5
The first stars are thought to be one of the dominant sources of hydrogen reionization in the early Universe, with their high luminosities and surface temperatures expected to driv…
The possible disappearance of a massive star in the low metallicity galaxy PHL 293B
Andrew Allan, Jose Groh, Andrea Mehner +4
We investigate a suspected very massive star in one of the most metal-poor dwarf galaxies, PHL~293B. Excitingly, we find the sudden disappearance of the stellar signatures from our…
SAEBench: A Comprehensive Benchmark for Sparse Autoencoders in Language Model Interpretability
Adam Karvonen, Can Rager, Johnny Lin +12
Sparse autoencoders (SAEs) are a popular technique for interpreting language model activations, and there is extensive recent work on improving SAE effectiveness. However, most pri…
Coupling thermal evolution of planets and hydrodynamic atmospheric escape in MESA
Daria Kubyshkina, Aline A. Vidotto, Luca Fossati +1
The long-term evolution of hydrogen-dominated atmospheres of sub-Neptune-like planets is mostly controlled by two factors: a slow dissipation of the gravitational energy acquired a…
Massive black holes regulated by luminous blue variable mass loss and magnetic fields
Jose H. Groh, Eoin Farrell, Georges Meynet +5
We investigate the effects of mass loss during the main-sequence (MS) and post-MS phases of massive star evolution on black hole (BH) birth masses. We compute solar metallicity Gen…
Numerical experiments to help understand cause and effect in massive star evolution
Eoin Farrell, Jose Groh, Georges Meynet +1
The evolution of massive stars is affected by a variety of physical processes including convection, rotation, mass loss and binary interaction. Because these processes modify the i…
The Initial Magnetic Field Distribution in AB Stars
Eoin Farrell, Adam S. Jermyn, Matteo Cantiello +1
Stars are born with magnetic fields, but the distribution of their initial field strengths remains uncertain. We combine observations with theoretical models of magnetic field evol…
The Uncertain Masses of Progenitors of Core Collapse Supernovae and Direct Collapse Black Holes
Eoin Farrell, Jose Groh, Georges Meynet +1
We show that it is not possible to determine the final mass of a red supergiant (RSG) at the pre-supernova (SN) stage from its luminosity and effective temperatur…
The impact of rotational mixing in intermediate-age star clusters with extended main-sequence turn-offs and extended red clumps
Lorenzo Martinelli, Andrea Miglio, Gaël Buldgen +6
The extended main-sequence turn-offs (eMSTOs) and extended red clumps (eRCs) observed in intermediate-age star clusters challenge the traditional understanding of clusters as simpl…
Detailed Simulations of Massive Hierarchical Triple Star Systems - Exploring the impact of the stellar physics on the evolutionary pathways of massive hierarchical triple systems
Luca Sciarini, Sylvia Ekström, Floris Kummer +4
Recent observations estimate that 30% of early B and O-type stars are found in triple systems. So far, the evolution of triple star systems has mainly been modeled using fast stell…
Impact of different approaches for computing rotating stellar models I. The solar metallicity case
Devesh Nandal, Georges Meynet, Sylvia Ekström +6
The physics of stellar rotation plays a crucial role in the evolution of stars, their final fate and the properties of compact remnants. Diverse approaches have been adopted to inc…
Explaining the high nitrogen abundances observed in high-z galaxies via population III stars of a few thousand solar masses
Devesh Nandal, John A. Regan, Tyrone E. Woods +3
The chemical enrichment of the early Universe is a crucial element in the formation and evolution of galaxies, and Population III (PopIII) stars must play a vital role in this proc…