Explanipedia

Brown Dwarf Formation through Gravitational Collapse: Insights from 3D Numerical Simulations Open

A. Ahmad, B. Commerçon, G. Chabrier, Antonin Borderies · 2025

The formation mechanism of brown dwarfs (BDs), whether akin to stars or ejected planetary-mass objects, remains debated. We present the first 3D radiation-MHD simulations of magnetized, turbulent, gravitationally unstable low-mass cores (0…

Turn up the light: Radiative efficiency of protostars at birth Open

Asmita Bhandare, A. Ahmad, B. Commerçon · 2025

The early stages of stellar birth comprise a two-step process involving the formation of two hydrostatic cores. The second step of gravitational collapse sets the radiative efficiency and accretion rate of the young protostar. These two pa…

Two-moment cosmic ray transport in RAMSES Open

Joakim Rosdahl, Yohan Dubois, B. Commerçon, N. Diallo, N. Lin , et al. · 2025

Cosmic rays (CRs) are an important source of feedback in a variety of astrophysical contexts. Magneto-hydrodynamical (MHD) simulations treating CRs as a fluid have shown that how their feedback operates is strongly dependent on their trans…

Brown Dwarf Formation Through Gravitational Collapse: Insights From 3D Numerical Simulations Open

A. Ahmad, B. Commerçon, G. Chabrier, Antonin Borderies · 2025

The formation mechanism of Brown Dwarfs (BDs), whether akin to stars or ejected planetary-mass objects, remains debated. We present the first 3D radiation-MHD simulations of magnetized, turbulent, gravitationally unstable low-mass cores ($…

The influence of magnetic fields on second-generation star formation in globular clusters Open

Asiyeh Yaghoobi, F. S. Tabatabaei, Joakim Rosdahl, B. Commerçon, Somayeh Sheikhnezami , et al. · 2025

We investigate the previously unexplored role of magnetic fields in the formation of second-generation (SG) stars in proto-globular clusters (GCs) using 3D radiation-magnetohydrodynamical simulations. This study is based on the asymptotic …

PRODIGE – envelope to disk with NOEMA Open

J.J. Miranzo-Pastor, A. Fuente, D. Navarro-Almaida, J. E. Pineda, Dominique Segura-Cox , et al. · 2025

Context . Determining the amount of sulfur in volatiles and refractories in the interstellar medium remains one of the main problems in astrochemistry. The detection of H 2 S ices, which are thought to be one of the main sulfur reservoirs,…

The Influence of Magnetic Fields on Second-Generation Star Formation in Globular Clusters Open

Asiyeh Yaghoobi, F. S. Tabatabaei, Joakim Rosdahl, B. Commerçon, Somayeh Sheikhnezami , et al. · 2025

We investigate the previously unexplored role of magnetic fields in the formation of second-generation (SG) stars in proto-globular clusters (GCs) using 3D radiation-magnetohydrodynamical simulations. This study is based on the asymptotic …

Cosmic ray and plasma coupling for isothermal supersonic turbulence in the magnetized interstellar medium Open

Matt L. Sampson, James R. Beattie, Romain Teyssier, Philipp Kempski, Eric R Moseley , et al. · 2025

Cosmic rays (CRs) are an integral part of the non-thermal pressure budget in the interstellar medium (ISM) and are the leading-order ionization mechanism in cold molecular clouds. We study the impacts that different microphysical CR diffus…

Massive star cluster seeds form by gravo-turbulent flows rather than magnetized collapse Open

Junhao Liu, Patricio Sanhueza, Piyali Saha, Kaho Morii, A. Maury , et al. · 2025

High-mass stars form in protoclusters, where gravo-magnetic processes shape massive star-forming clouds and clumps to be elongated preferentially perpendicular to magnetic fields. Yet it remains unclear whether magnetic fields still govern…

Birth of magnetized low-mass protostars and circumstellar disks Open

A. Ahmad, M. González, P. Hennebelle, U. Lebreuilly, B. Commerçon · 2025

Context. Providing a comprehensive description of the birth of protostars and circumstellar disks, and how these two evolve over time, are among the goals of stellar formation theory. Although the two objects are often studied separately o…

Magnetic Fields in Massive Star-forming Regions (MagMaR). V. The Magnetic Field at the Onset of High-mass Star Formation Open

Patricio Sanhueza, Junhao Liu, Kaho Morii, J. M. Girart, Qizhou Zhang , et al. · 2025

A complete understanding of the initial conditions of high-mass star formation and what processes determine multiplicity requires the study of the magnetic field in young massive cores. Using Atacama Large Millimeter/submillimeter Array (A…

Dust evolution by chemisputtering during protostellar formation Open

Antonin Borderies, B. Commerçon, Bernard Bourdon · 2025

Dust grains play a crucial role in the modeling of protostellar formation, particularly through their opacity and interaction with the magnetic field. The destruction of dust grains in numerical simulations is currently modeled primarily b…

Dust evolution by chemisputtering during protostellar formation Open

Antonin Borderies, B. Commerçon, Bernard Bourdon · 2025

Context . Dust grains play a crucial role in the modeling of protostellar formation, particularly through their opacity and interaction with the magnetic field. The destruction of dust grains in numerical simulations is currently modeled p…

Magnetic Fields in Massive Star-forming Regions (MagMaR). V. The Magnetic Field at the Onset of High-mass Star Formation Open

Patricio Sanhueza, Junhao Liu, Kaho Morii, J. M. Girart, Qizhou Zhang , et al. · 2024

A complete understanding of the initial conditions of high-mass star formation and what processes determine multiplicity require the study of the magnetic field (B-field) in young, massive cores. Using ALMA 250 GHz polarization (0.3" = 100…

Formation and evolution of a protoplanetary disk: Combining observations, simulations, and cosmochemical constraints Open

Alessandro Morbidelli, Yves Marrocchi, A. Ahmad, Asmita Bhandare, S. Charnoz , et al. · 2024

Context. The formation and evolution of protoplanetary disks remains elusive. We have numerous astronomical observations of young stellar objects of different ages with their envelopes and/or disks. Moreover, in the last decade, there has …

Formation and evolution of a protoplanetary disk: combining observations, simulations and cosmochemical constraints Open

Alessandro Morbidelli, Yves Marrocchi, A. Ahmad, Asmita Bhandare, S. Charnoz , et al. · 2024

We present a plausible and coherent view of the evolution of the protosolar disk that is consistent with the cosmochemical constraints and compatible with observations of other protoplanetary disks and sophisticated numerical simulations. …

NASCENT-stars large program: origin of molecular complexity towards emerging high-mass protostars Open

T. Csengeri, Bontemps Baudry, L. Bouscasse, A. López-Sepulcre, Romane Le Gal , et al. · 2024

During the star formation process, the interstellar medium gets enriched in a complex zoo of molecules. The extremely rich chemistry of the star forming gas holds the key to constrain the link between the chemistry of disks and their formi…

Discs are born eccentric Open

B. Commerçon, Francesco Lovascio, Elliot M Lynch, Enrico Ragusa · 2024

Context. Recent observations have begun probing the early phases of disc formation, but little data yet exists on disc structure and morphology of Class 0 objects. Using simulations, we are able to lay out predictions of disc morphologies …

Redesign of astrophysical codes for exascale computing: the SPACE experience Open

Giuliano Taffoni, A. Mignone, L. Tornatore, ‬‬‬‬‬‬Eva Sciacca, Massimiliano Guarrasi , et al. · 2024

High Performance Computing based simulations are crucial in Astrophysics and Cosmology, helping scientists investigate and understand complex astrophysical phenomena. Taking advantage of Exascale computing capabilities is essential for the…

Past activity of Sgr A<sup>⋆</sup> is unlikely to affect the local cosmic-ray spectrum up to the TeV regime Open

Martin Fournier, Jérémy Fensch, B. Commerçon · 2024

Context The presence of kiloparsec-sized bubble structures on both sides of the Galactic plane suggests active phases of Sgr A ⋆ , the central supermassive black hole of the Milky Way in the last 1–6 Myr. We investigated the contribution o…

Mixing is easy: New insights for cosmochemical evolution from pre-stellar core collapse Open

Asmita Bhandare, B. Commerçon, Guillaume Laibe, Mario Flock, R. Kuiper , et al. · 2024

Context . Signposts of early planet formation are ubiquitous in substructured young discs. Dense, hot, and high-pressure regions that formed during the gravitational collapse process, integral to star formation, facilitate dynamical mixing…

Formation of low-mass protostars and their circumstellar disks Open

A. Ahmad, M. González, P. Hennebelle, B. Commerçon · 2024

Context. Understanding circumstellar disks is of prime importance in astrophysics; however, their birth process remains poorly constrained due to observational and numerical challenges. Recent numerical works have shown that the small-scal…

Grain growth and its chemical impact in the first hydrostatic core phase Open

D. Navarro-Almaida, U. Lebreuilly, P. Hennebelle, A. Fuente, B. Commerçon , et al. · 2024

Context. The first hydrostatic core (FHSC) phase is a brief stage in the protostellar evolution that is difficult to detect. Its chemical composition determine that of later evolutionary stages. Numerical simulations are the tool of choice…

Grain growth and its chemical impact in the first hydrostatic core phase Open

D. Navarro-Almaida, U. Lebreuilly, P. Hennebelle, A. Fuente, B. Commerçon , et al. · 2024

The first hydrostatic core (FHSC) phase is a brief stage in the protostellar evolution that is difficult to detect. Our goal is to characterize the chemical evolution of gas and dust during the formation of the FHSC. Moreover, we are inter…

Simulations of early structure formation: Properties of halos that host primordial star formation Open

Romain Lenoble, B. Commerçon, Joakim Rosdahl · 2024

Context. Population III (pop III) stars were born in halos characterised by a pristine gas composition. In such a halo, once the gas density reaches n H ∼ 1 cm −3 , molecular cooling leads to the collapse of the gas and the birth of pop II…

Synthetic populations of protoplanetary disks: Impact of magnetic fields and radiative transfer Open

U. Lebreuilly, P. Hennebelle, Tine Colman, A. Maury, Ngo-Duy Tung , et al. · 2023

Context . Protostellar disks are the product of angular momentum conservation during protostellar collapse. Understanding their formation is crucial because they are the birthplace of planets and their formation is also tightly related to …

Synthetic populations of protoplanetary disks. Impact of magnetic fields and radiative transfer Open

U. Lebreuilly, P. Hennebelle, Tine Colman, A. Maury, Ngo-Duy Tung , et al. · 2023

Protostellar disks are the product of angular momentum conservation during the protostellar collapse. Understanding their formation is crucial because they are the birthplace of planets and because their formation is tightly related to sta…

The birth and early evolution of a low-mass protostar Open

A. Ahmad, M. González, P. Hennebelle, B. Commerçon · 2023

Context. Understanding the collapse of dense molecular cloud cores to stellar densities and the subsequent evolution of the protostar is of importance to model the feedback effects such an object has on its surrounding environment, as well…

The birth and early evolution of a low mass protostar Open

A. Ahmad, M. González, P. Hennebelle, B. Commerçon · 2023

Understanding the collapse of dense molecular cloud cores to stellar densities and the subsequent evolution of the protostar is of importance to model the feedback effects such an object has on its surrounding environment, as well as descr…

Dust dynamics in current sheets within protoplanetary disks Open

U. Lebreuilly, Mordecai‐Mark Mac Low, B. Commerçon, D. S. Ebel · 2023

Context. Chondrules originate from the reprocessing of dust grains. They are key building blocks of telluric planets, yet their formation, which must happen in strongly localized regions of high temperature, remains poorly understood. Aims…

B. Commerçon YOU? Author Swipe