Stellar evolution
View article: TU-GUT-SYSY v23 – 10 December 2025: Stellar Evolution and Black Stars via Progressive Entanglement Saturation
TU-GUT-SYSY v23 – 10 December 2025: Stellar Evolution and Black Stars via Progressive Entanglement Saturation Open
v23 shows that stellar cores are regions of progressive entanglement saturation. Neutron stars with saturated cores ("black stars") are the observable intermediate phase between ordinary neutron stars and black holes. No new fields — pure …
View article: Data, Analysis, and Modeling for Henney et al. (2025)
Data, Analysis, and Modeling for Henney et al. (2025) Open
Observational data, analysis, and modeling that forms the basis of the paper: Kinematics and physical structure of Ou 5: A bipolar planetary nebula with extreme abundance discrepancy and an eclipsing binary core Henney et al., MNRAS in pre…
View article: Discovery of 79 <i>δ</i> Scuti Stars in NGC 3532 Suggests a Decrease of Pulsator Occurrence with Age
Discovery of 79 <i>δ</i> Scuti Stars in NGC 3532 Suggests a Decrease of Pulsator Occurrence with Age Open
Many A–F type stars do not display δ Scuti pulsations, despite being located within the instability strip. Open clusters provide a unique opportunity to study δ Scuti pulsations among coeval populations with uniform chemical composition. H…
View article: How the External Medium Outside Prestellar Cores Affects Protostellar Growth: Variations in Accretion Rate and Evolution of Disks and Outflows
How the External Medium Outside Prestellar Cores Affects Protostellar Growth: Variations in Accretion Rate and Evolution of Disks and Outflows Open
We investigate how the external medium surrounding prestellar cores affects the star formation process by conducting three-dimensional resistive magnetohydrodynamic simulations. The initial cores follow critical Bonnor–Ebert profiles and a…
View article: TU-GUT-SYSY v23 – 10 December 2025: Stellar Evolution and Black Stars via Progressive Entanglement Saturation
TU-GUT-SYSY v23 – 10 December 2025: Stellar Evolution and Black Stars via Progressive Entanglement Saturation Open
v23 shows that stellar cores are regions of progressive entanglement saturation. Neutron stars with saturated cores ("black stars") are the observable intermediate phase between ordinary neutron stars and black holes. No new fields — pure …
View article: 1000-Star Catalog for γ≈1 Universality in Astrophysical Turbulence-Kepler- TESS & HST Data Release
1000-Star Catalog for γ≈1 Universality in Astrophysical Turbulence-Kepler- TESS & HST Data Release Open
Title 1000-Star Catalog for γ≈1 Universality in Astrophysical Turbulence: Kepler, TESS & HST Data Release Authors Chowdhury, Faridul Islam (ORCID: 0000-0003-5187-0671) Grok (xAI) Publication date Today (auto-filled) Description: This 221-p…
View article: 1000-Star Catalog for γ≈1 Universality in Astrophysical Turbulence-Kepler- TESS & HST Data Release
1000-Star Catalog for γ≈1 Universality in Astrophysical Turbulence-Kepler- TESS & HST Data Release Open
Title 1000-Star Catalog for γ≈1 Universality in Astrophysical Turbulence: Kepler, TESS & HST Data Release Authors Chowdhury, Faridul Islam (ORCID: 0000-0003-5187-0671) Grok (xAI) Publication date Today (auto-filled) Description: This 221-p…
View article: Rethinking stellar and planetary evolution in the Robitaillian paradigm – a first thread-based pre-formal open peer review dialogue
Rethinking stellar and planetary evolution in the Robitaillian paradigm – a first thread-based pre-formal open peer review dialogue Open
In order to resolve several issues with the standard gaseous solar model, Pierre-Marie Robitaille has introduced a liquid metallic hydrogen model of the Sun, based on various observations and theoretical insights. Working further on this s…
View article: Data, Analysis, and Modeling for Henney et al. (2025)
Data, Analysis, and Modeling for Henney et al. (2025) Open
Observational data, analysis, and modeling that forms the basis of the paper: Kinematics and physical structure of Ou 5: A bipolar planetary nebula with extreme abundance discrepancy and an eclipsing binary core Henney et al., MNRAS in pre…
View article: Near-IR CO and CN in classical Cepheids
Near-IR CO and CN in classical Cepheids Open
We present medium resolution near-infrared spectral measurements of the carbon monoxide (CO) and the cyano radical (CN) features in 12 Galactic classical Cepheids. The pulsation periods of our sample range from 5.5 to 69 days, and the star…
View article: FIRESTORM I: Stellar Feedback and Gas Kinematics in the Evolved W40 Hub-Filament System
FIRESTORM I: Stellar Feedback and Gas Kinematics in the Evolved W40 Hub-Filament System Open
The FIRESTORM project--Feedback-Induced Regions and Emission from Star-forming Tracers of ObseRvable Molecular Gas--has targeted four star-forming regions to quantify the impact of stellar feedback on star formation. In this paper, we pres…
View article: The Impact of Irradiation on the Radius and Thermal Evolution of Transiting Brown Dwarfs
The Impact of Irradiation on the Radius and Thermal Evolution of Transiting Brown Dwarfs Open
Masses and radii of transiting brown dwarfs can be measured directly in contrast to isolated field brown dwarfs, whose mass and radius inferences are model dependent. Therefore, transiting brown dwarfs are a testbed for the interior and ev…
View article: The Birth of Be Star Disks II. A High-Resolution Spectroscopic Campaign and TESS Observations of an Outburst of the Classical Be star λ Pavonis
The Birth of Be Star Disks II. A High-Resolution Spectroscopic Campaign and TESS Observations of an Outburst of the Classical Be star λ Pavonis Open
Be stars are non-supergiant, rapidly rotating B stars that have shown emission lines originating in a circumstellar disk. The exact mechanisms that lead to disk formation and dissipation are not fully known although progress has been made …
View article: Theoretical Models for the Late Thermal Pulse in Post-asymptotic Giant Branch Stars: The Case of DY Cen
Theoretical Models for the Late Thermal Pulse in Post-asymptotic Giant Branch Stars: The Case of DY Cen Open
We present theoretical predictions of the born-again scenario for post-asymptotic giant branch stars. An extensive model grid for born-again objects has been constructed, particularly including models for the very late thermal pulse with a…
View article: The Birth of Be Star Disks II. A High-Resolution Spectroscopic Campaign and TESS Observations of an Outburst of the Classical Be star λ Pavonis
The Birth of Be Star Disks II. A High-Resolution Spectroscopic Campaign and TESS Observations of an Outburst of the Classical Be star λ Pavonis Open
Be stars are non-supergiant, rapidly rotating B stars that have shown emission lines originating in a circumstellar disk. The exact mechanisms that lead to disk formation and dissipation are not fully known although progress has been made …
View article: Evolution of ultracompact neutron star--helium star binaries
Evolution of ultracompact neutron star--helium star binaries Open
Ultracompact binaries (detached and X-ray-emitting) are regularly detected and studied; however, it is not known whether even more compact configurations featuring degenerate stars exist. The recent discovery of PSR J1928+1815, which has a…
View article: The Head-on Collision of a Neutron Star with a White Dwarf
The Head-on Collision of a Neutron Star with a White Dwarf Open
We have computed the physical processes involved in a head-on collision between a neutron star (NS) and a white dwarf (WD). The outcomes of such collisions vary depending on the mass and type of the WD. We have separately examined the dyna…
View article: Supernovae Shock Breakout from Red Supergiants in Two Dimensions
Supernovae Shock Breakout from Red Supergiants in Two Dimensions Open
We present new two-dimensional radiation hydrodynamic simulations of supernova shock breakout from red supergiants using the $\texttt{CASTRO}$ code. Our progenitors are 20 and 25 M$_{\odot}$ solar-metallicity stars evolved from the zero-ag…
View article: Exploring the binary origin of B and Be rapid rotators
Exploring the binary origin of B and Be rapid rotators Open
Observational evidence has continued to mount that a significant fraction of rapidly rotating early-B type stars are products of binary mass transfer. However, very few mid- and late-type B stars with rapid rotation have been demonstrated …
View article: FIRESTORM I: Stellar Feedback and Gas Kinematics in the Evolved W40 Hub-Filament System
FIRESTORM I: Stellar Feedback and Gas Kinematics in the Evolved W40 Hub-Filament System Open
The FIRESTORM project--Feedback-Induced Regions and Emission from Star-forming Tracers of ObseRvable Molecular Gas--has targeted four star-forming regions to quantify the impact of stellar feedback on star formation. In this paper, we pres…
View article: Exploring the binary origin of B and Be rapid rotators
Exploring the binary origin of B and Be rapid rotators Open
Observational evidence has continued to mount that a significant fraction of rapidly rotating early-B type stars are products of binary mass transfer. However, very few mid- and late-type B stars with rapid rotation have been demonstrated …
View article: Near-IR CO and CN in classical Cepheids
Near-IR CO and CN in classical Cepheids Open
We present medium resolution near-infrared spectral measurements of the carbon monoxide (CO) and the cyano radical (CN) features in 12 Galactic classical Cepheids. The pulsation periods of our sample range from 5.5 to 69 days, and the star…
View article: Chemical analysis of the Milky Way's Nuclear Star Cluster: Evidence for a metallicity gradient
Chemical analysis of the Milky Way's Nuclear Star Cluster: Evidence for a metallicity gradient Open
The Milky Way nuclear star cluster (MWNSC) is located together with its surrounding nuclear stellar disc (MWNSD) in the Galactic centre and they dominate the gravitational potential within the inner 300\,pc. However, the formation and evol…
View article: Chemical analysis of the Milky Way's Nuclear Star Cluster: Evidence for a metallicity gradient
Chemical analysis of the Milky Way's Nuclear Star Cluster: Evidence for a metallicity gradient Open
The Milky Way nuclear star cluster (MWNSC) is located together with its surrounding nuclear stellar disc (MWNSD) in the Galactic centre and they dominate the gravitational potential within the inner 300\,pc. However, the formation and evol…
View article: Supernovae Shock Breakout from Red Supergiants in Two Dimensions
Supernovae Shock Breakout from Red Supergiants in Two Dimensions Open
We present new two-dimensional radiation hydrodynamic simulations of supernova shock breakout from red supergiants using the $\texttt{CASTRO}$ code. Our progenitors are 20 and 25 M$_{\odot}$ solar-metallicity stars evolved from the zero-ag…
View article: The Impact of Irradiation on the Radius and Thermal Evolution of Transiting Brown Dwarfs
The Impact of Irradiation on the Radius and Thermal Evolution of Transiting Brown Dwarfs Open
Masses and radii of transiting brown dwarfs can be measured directly in contrast to isolated field brown dwarfs, whose mass and radius inferences are model dependent. Therefore, transiting brown dwarfs are a testbed for the interior and ev…
View article: JWST TRAPPIST-1 e/b Program: Motivation and first observations
JWST TRAPPIST-1 e/b Program: Motivation and first observations Open
One of the forefront goals in the field of exoplanets is the detection of an atmosphere on a temperate terrestrial exoplanet, and among the best suited systems to do so is TRAPPIST-1. However, JWST transit observations of the TRAPPIST-1 pl…
View article: BSN: Light Curve Modeling and Orbital Evolution of the Total-Eclipse Contact Binary EZ Oct
BSN: Light Curve Modeling and Orbital Evolution of the Total-Eclipse Contact Binary EZ Oct Open
We present the first detailed multiband (BVR_cI_c and TESS) photometric analysis of the short-period binary EZ Oct. This study combines ground-based observations conducted at a Southern Hemisphere observatory in Argentina with data from th…
View article: Revisiting the Evolutionary Status of Massive Stars at the central parsec of the Milky Way
Revisiting the Evolutionary Status of Massive Stars at the central parsec of the Milky Way Open
Massive stars and their winds have a large influence in their environment, e.g, determining the accretion rate on to the Galactic Centre (GC) super-massive black hole Sgr A*. The winds of those stars collide and are accreted, at a rate tha…
View article: Analytical Solutions for the Dynamics of Planetary Nebulae with and without Common Envelope Evolution
Analytical Solutions for the Dynamics of Planetary Nebulae with and without Common Envelope Evolution Open
We present new analytical solutions for the dynamics of planetary nebulae. These equations consider the temporal variation of the mechanical luminosity as well as the common envelope evolution scenario. By comparing a database of nebulae w…