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Marco Tarantino

Publications and source records attributed to Marco Tarantino.

3 recordsLinked to original sources

Using a neural network approach and starspots dependent models to predict effective temperatures and ages of young stars

This study presents a statistical approach to accurately predict the effective temperatures of pre-main sequence stars, which are necessary for determining stellar ages using the isochrone methodology and cutting-age starspots-dependent models. By training a Neural Network model on high-quality spectroscopic temperatures from the Gaia-ESO Survey as the response variable, and using photometric data from Gaia DR3 and 2MASS catalogs as explanatory variables, we implemented a methodology to accurately derive the effective temperatures of much larger populations of stars for which only photometric data are available. The model demonstrated robust performance for low-mass stars with temperatures below 7000 K, including young stars, the primary focus of this work. Predicted temperatures were employed to construct Hertzsprung-Russell diagrams and to predict stellar ages of different young clusters and star forming regions through isochrone interpolation, achieving excellent agreement with spectroscopic-based ages and literature values derived from model-independent methods like lithium equivalent widths. The inclusion of starspot evolutionary models improved the age predictions, providing a more accurate description of stellar properties. Additionally, the results regarding the effective temperature and age predictions of the young clusters provide evidence for intrinsic age spreads in the youngest clusters, suggesting multiple formation events over time.

astro-ph.SR

The Dynamics of the Milky Way: Unveiling the 6D Skeleton of Star Formation in the 2040s

The Milky Way (MW) is our unique laboratory to test star formation theories at the level of individual stars, serving as the Rosetta Stone to interpret extragalactic observations. The proposed White Paper focuses on the following key questions regarding the structure and evolution of the MW traced by young stellar populations: Q1. How do large-scale dynamical instabilities, like warps and vertical waves, drive the star formation of the Galactic thin disk? Q2. Do star-forming regions form stochastically, driven by local self-propagating feedback, or are they triggered by a common dynamical process acting on Galactic scales? Do internal feedback loops and external interactions tend to sustain or quench star formation in the MW? Q3. Are the clustered star-forming regions the only environments where stars form, or can stars also form in more diffuse structures such as the stellar strings?

astro-ph.IM

Recollements from Cotorsion Pairs

Given a complete hereditary cotorsion pair $(\mathcal{A},\mathcal{B})$ in a Grothendieck category $\mathcal{G}$, the derived category $\mathcal{D}(\mathcal{B})$ of the exact category $\mathcal{B}$ is defined as the quotient of the category $\mathrm{Ch}(\mathcal{B})$, of unbounded complexes with terms in $\mathcal{B}$, modulo the subcategory $\widetilde{\mathcal{B}}$ consisting of the acyclic complexes with terms in $\mathcal{B}$ and cycles in $\mathcal{B}$. We restrict our attention to the cotorsion pairs such that $\widetilde{\mathcal{B}}$ coincides with the class $ex\mathcal{B}$ of the acyclic complexes of $\mathrm{Ch}(\mathcal{G})$ with terms in $\mathcal{B}$. In this case the derived category $\mathcal{D}(\mathcal{B})$ fits into a recollement $\dfrac{ex\mathcal{B}}{\sim} \mathrel{\substack{\textstyle\leftarrow\textstyle\rightarrow\textstyle\leftarrow}} {K(\mathcal{B})} \mathrel{\substack{\textstyle\leftarrow\textstyle\rightarrow\textstyle\leftarrow}} {\dfrac{\mathrm{Ch}(\mathcal{B})}{ex\mathcal{B} }}$. We will explore the conditions under which $\mathrm{ex}\,\mathcal{B}=\widetilde{\mathcal{B}}$ and provide many examples. Symmetrically, we prove analogous results for the exact category $\mathcal{A}$.

math.CT