arXiv subjects

Michelangelo Pantaleoni González

Publications and source records attributed to Michelangelo Pantaleoni González.

5 recordsLinked to original sources

arXiv2026

The Nearby Star Formation and Supernova Histories Reconstructed from Young Star Clusters

We reconstruct the recent star formation and core-collapse supernova (ccSN) histories of the Solar Neighborhood from the past trajectories of young star clusters. Using a \textit{Gaia}-based cluster sample with newly derived ages, masses, and bulk 3D velocities, we integrate orbits backward in an assumed axisymmetric Galactic potential and combine the trajectories with IMF sampling and stellar lifetimes to infer ccSN times and locations over the past 50 Myr. The result is an all-sky, 3D, time-resolved map of nearby ccSN activity for comparison with high-resolution 3D views of the local interstellar medium. The 0--15 Myr map shows strong enhancements toward Orion, Vela, Sco--Cen, and Cepheus, many within present-day cavities and shells. At earlier times, the dominant enhancements trace the Collinder 135, Messier 6, and Alpha Persei cluster families, showing how the remnants of massive star-forming complexes have shaped the recent local feedback history. We recover a bursty star formation history followed by a delayed, smoother ccSN history. Over the last 40 Myr, the mean star formation and ccSN rates are $823~M_\odot~\mathrm{Myr}^{-1}$ and $7.7~\mathrm{Myr}^{-1}$, respectively, corresponding to a Milky Way rate of $0.55\pm0.03~\mathrm{century}^{-1}$. Present-day OB-star catalogs yield rates ranging from agreement with the cluster reconstruction to several times higher. Because the catalogs overlap weakly and require different corrections, we do not rescale the ccSN map. Our reconstruction provides an empirical framework for connecting the recent history of massive-star feedback to the 3D structure and life cycle of gas in the nearby Milky Way.

astro-ph.GA↗

arXiv2026

Requiem for a belt: A spatial and kinematical reinterpretation of Gould's Belt in light of Gaia

We reassess the long-standing idea of Gould's Belt using Gaia DR3 for a sample of young massive stars and nearby young clusters. The structure surrounding the Sun, often interpreted as an inclined, expanding, and rotating ring, emerges in our analysis as a transient alignment of a few cluster families rather than an individual, coherent dynamical feature. By combining the ALS III catalog of OB stars with a homogeneous sample of clusters younger than 70 Myr, and by tracing their motions in a realistic Galactic potential, we show that neither the spatial distribution nor the kinematics form a unified system. The inferred expansion, rotation, and bulk motion of the Belt can be reproduced by the superposition of the $α$Per, Cr135, M6, and $γ$Vel cluster families and are further amplified by solar reflex motion and historical assumptions about the local standard of rest (LSR). The classic inclined geometry is largely explained by the oscillatory pattern of the Radcliffe Wave, which contributes a major arc of the supposed ring. Taken together, these results indicate that Gould's Belt is not a physical structure but a 3D asterism shaped by a complex local star formation history, observational biases, and projection effects.

astro-ph.GA↗

arXiv2025

The superclouds of the local Milky Way

Recent 3D dust maps of the local Milky Way are revolutionizing our understanding of the Sun's Galactic neighborhood, providing much needed insight into the large-scale organization of the interstellar medium. Focusing on the largest scales in $\textit{Gaia}$-based 3D dust maps, we find a pattern of seven highly elongated, mostly parallel structures in the local $\sim 5\,\mathrm{kpc}^2$, five of which were previously unknown. These structures show pitch angles of $33.5 \pm 4.0 ^\circ$ and masses ranging from $10^5$ to $10^6$ $\mathrm{M}_\odot$. We refer to these structures as superclouds. Nearly all known star-forming regions in the solar neighborhood lie within the superclouds, primarily along their central axes, supporting the idea that they act as gas reservoirs for the formation of giant molecular clouds. All but one of the seven superclouds show an underlying undulation, indicating that this is not a property unique to the Radcliffe Wave. We find that while the superclouds have linear masses that vary by about a factor of 4, their volume densities only vary by about 10$\%$. This suggests that superclouds self-regulate their physical sizes and internal structure to maintain pressure equilibrium with their environment. These findings establish a new framework for understanding how large-scale Galactic structures shape the conditions for star formation in the solar vicinity, and likely in galaxies like the Milky Way.

astro-ph.GA↗

arXiv2025

A Novel Method to Estimate the FUV Flux and a Catalogue for Star-Hosting Discs in Nearby Star-Forming Regions

Protoplanetary discs, when externally irradiated by Far Ultraviolet (FUV) photons from OBA-type stars, lose material through photoevaporative winds, reducing the amount of material available to form planets. Understanding the link between environmental irradiation and observed disc properties requires accurately evaluating the FUV flux at star-hosting discs, which can be challenging due stellar parallax uncertainties. In this paper, we address this issue proposing a novel approach: using the local density distribution of a star-forming region (i.e. 2D pairwise star separations distribution) and assuming isotropy, we infer 3D separations between star-hosting discs and massive stars. We test this approach on synthetic clusters, showing that it significantly improves the accuracy compared to previous methods. We compute FUV fluxes for a large sample of star-bearing discs in 7 regions within 200 pc, 6 regions in Orion, and Serpens sub-regions, providing a publicly accessible catalogue. We find that discs in regions hosting late-type B and early-type A stars can reach non-negligible irradiation levels for disc evolution (10-100 G0). We investigate dust disc masses relative to FUV fluxes detecting hints of a negative correlation when restricting to average region ages. However, we emphasize the need for more stellar and disc measurements at >10^2 G0 to probe the dependence of disc properties on the environmental irradiation. Including average interstellar dust extinction, median FUV fluxes are not significantly attenuated, though this result may change if high-resolution 3D dust extinction maps were available. The method presented in this work is a powerful tool that can be expanded to additional regions.

astro-ph.EP↗

arXiv2023

Clustering properties of intermediate and high-mass Young Stellar Objects

We have selected 337 intermediate and high-mass YSOs ($1.5$ to $20$ M$_{\odot}$) well-characterised with spectroscopy. By means of the clustering algorithm HDBSCAN, we study their clustering and association properties in the Gaia DR3 catalogue as a function of stellar mass. We find that the lower mass YSOs ($1.5-4$ M$_{\odot}$) have clustering rates of $55-60\%$ in Gaia astrometric space, a percentage similar to the one found in the T Tauri regime. However, intermediate-mass YSOs in the range $4-10$ M$_{\odot}$ show a decreasing clustering rate with stellar mass, down to $27\%$. We find tentative evidence suggesting that massive YSOs ($>10$ M$_{\odot}$) often appear $-$yet not always$-$ clustered. We put forward the idea that most massive YSOs form via a mechanism that demands many low-mass stars around them. However, intermediate-mass YSOs form in a classical core-collapse T Tauri way, yet they do not appear often in the clusters around massive YSOs. We also find that intermediate and high-mass YSOs become less clustered with decreasing disk emission and accretion rate. This points towards an evolution with time. For those sources that appear clustered, no major correlation is found between their stellar properties and the cluster sizes, number of cluster members, cluster densities, or distance to cluster centres. In doing this analysis, we report the identification of 55 new clusters. We present tabulated all the derived cluster parameters for the considered intermediate and high-mass YSOs.

astro-ph.SR↗