Protoplanetary disks are fundamental objects for our understanding of planet formation. Whereas they are in essence a consequence of angular momentum conservation, the exact amount of mass and angular momentum which are delivered towards the proto-star remain largely unknown. Indeed, this process seems to be largelly controlled by magnetic field and more specifically by magnetic braking....
Molecular are the sites of star formation, made by networks of filaments (e.g., Andre’ et al. 2014, Hacar et al. 2023).
Individual filaments composing a molecular cloud accumulate mass by accretion from the parental cloud, until they become gravitationally unstable and fragment into cores, that eventually collapse into stars and stellar clusters. The candidates for supporting the clouds are...
Investigating the formation of the most massive stars has since ever been a theoretical challenge and a difficult observational task. Substantial progress has been made recently on both fronts and it appears that circumstellar accretion disks (and the associated jets) are key to explain how these stars form. We will report on our contribution to this topic in the last twenty years, with...
As a stellar group forms within its parent molecular cloud, new members first appear in the deep interior. Theory suggests, and observations confirm, that these crowded stars continually diffuse outward. I suggest that they also leak out of the cloud, to form an expanding envelope which I call the ``stellar mantle." In a nascent OB association, the mantle remains nested deep inside the...
Pedro R. Rivera-Órtiz, Basmah Riaz, Gabriel Verrier, Shingo Nozaki, Vianey Camacho
The origin of stellar masses and the link between core and stellar mass distributions (CMF and IMF respectively) are a central open issue in astrophysics. I will present the ALMA-IMF Large Program, whose goal is to determine if and how the origin of the IMF depends on the cloud characteristics and evolution. We surveyed 15 massive protoclusters covering a wide variety of Galactic environments...
A complete understanding of high-mass (> 8 M$_{Sun}$) star formation, including the overall process of jet emission and its behavior, remains elusive. Whether or not the accretion variability broadly observed in low-mass star formation is also a common process regulating the formation of massive stars has been highly debated in the last decade. We have recently discovered that the 1.3 cm...
Dust grains are essential ingredients in star formation and play a significant role in gas/dust dynamics, chemical reactions, and radiative transfer. The efficiency of all these physical processes depends on the grain-size distribution and how it evolves in time. Thus, accurate dust modeling is a much needed feature of star formation simulations. Dust growth and fragmentation are...
Stars form within dense cores embedded in turbulent molecular clouds. In this study, we investigate the cloud fragmentation process in Galactic molecular clouds with various star formation acttivity. Using astrodendro, we identified over $10^4$ dense cores across both nearby molecular clouds and high-mass star-forming clumps. Our central hypothesis is that core mass and separation provide key...
The formation of high-mass stars remains a complex and not fully understood process, differing significantly from that of low-mass stars. Understanding their early evolutionary stages is crucial for uncovering the mechanisms governing their formation and their impact on galactic evolution.
In this poster I present a study of the infall dynamics of dense cores (1000-3000 AU) associated with...
Explosive outflows (EOs) can significantly influence the structure of star-forming environments. EOs present a more complex scenario than conventional bipolar molecular outflows driven by jets and winds. Observed in high-mass star-forming regions, they consist of numerous dense clumps leading gaseous filaments spreading nearly isotropically from a common center. They have been identified in...
We investigate the kinetic and magnetic energy budget in a hub-filament system that arises self-consistently in an adaptive mesh refinement (AMR) simulation of a molecular cloud undergoing global hierarchical collapse (GHC). Our goal is to assess whether the energy distribution and dynamics of the formed structure are consistent with observations and to explore the role of magnetic fields...
The physical mechanisms behind the fragmentation of high-mass dense clumps into compact star-forming cores and the properties of these cores are fundamental topics that are heavily investigated in current astrophysical research. The ALMAGAL survey (Molinari et al. 2025, A&A, in press) provides the opportunity to study this process at an unprecedented level of detail and statistical...
Star formation, particularly in massive star-forming regions, is a complex, multi-scale process.
To explore the fundamental mechanisms driving the collapse of parsec-scale clumps, ultimately shaping the star-formation outcome, the Rosetta Stone project was developed. This project provides an end-to-end (simulations ⇔ observations) framework for comparing observational data with numerical...
