Nucleosynthesis and molecular processes in the late stages of Stellar Evolution

    General
    Description

    Low- to intermediate-mass (M < 8 solar masses, Ms) stars represent the majority of stars in the Cosmos. They finish their lives on the Asymptotic Giant Branch (AGB) - just before they form planetary nebulae (PNe) - where they experience complex nucleosynthetic and molecular processes. AGB stars are important contributors to the enrichment of the interstellar medium where new stars/planets are born (including our own Early Solar System, ESS), and to the chemical evolution of stellar systems like globular clusters (GCs) and galaxies. In particular, the more massive (M > 4-5 Ms) AGB stars synthesize very different (radio)isotopes from those formed by lower mass AGB stars and Supernova detonations, as a consequence of different nucleosynthesis mechanisms. Evolved stars in the transition phase between AGB stars and PNe also form diverse organic compounds like PAHs, and fullerene and graphene molecular nanostructures, being a wonderful laboratory for Astrochemistry. On-going massive surveys like SDSS-IV/APOGEE-2 and the upcoming James Webb Space Telescope (JWST) represent a fundamental step forward to understand the nucleosynthesis and molecular processes in evolved stars. We aim to explore the nucleosynthesis of light and heavy (radio)isotopes in AGB stars and how they contribute to the ESS radioactive inventory as well as to the formation and evolution of GCs and galaxies. We also aim at understanding the top-down formation process of fullerene and graphene molecular nanostructures in evolved stars. Finally, it is intended to perform data mining with the Gaia satellite, in order to study the AGB- PNe evolutionary phase. In addition we aim to use the GALEX database to discover binary central stars in Galactic PNe.

    Principal investigator

    1. During 2020, we have published 37 papers in high-impact international refereed astronomical journals (including one invited review) and 2 papers in the Chemistry -Physics journal FNCN.

    2. Phosphorus-rich stars with an extremely peculiar chemical abundance pattern have been discovered for the first time, challenging the theoretical nucleosynthesis predictions.

    3. It was demonstrated that the P-rich star progenitors represent a new site for s-process nucleosynthesis, with important implications for the chemical evolution of our Galaxy.

    Related publications

    Phase-transfer catalysis in the oxidation of C60 and C70 fullerene with KMnO4 and crown ether 2018FNCN...26..578C
    Raman, FT-IR spectroscopy and morphology of carbon dust from carbon arc in liquid benzene 2018FNCN...26..654G
    The Second APOKASC Catalog: The Empirical Approach 2018ApJS..239...32P
    Comprehensive comparison between APOGEE and LAMOST. Radial velocities and atmospheric stellar parameters 2018A&A...620A..76A
    When binaries keep track of recent nucleosynthesis. The Zr-Nb pair in extrinsic stars as an s-process diagnostic 2018A&A...618A..32K
    The Origin of the 300 km s‑1 Stream near Segue 1 2018ApJ...866...42F
    The Gaia-ESO Survey: the origin and evolution of s-process elements 2018A&A...617A.106M
    The Gaia-ESO Survey: properties of newly discovered Li-rich giants 2018A&A...617A...4S
    Modeling dust emission in PN IC 418 2018A&A...617A..85G
    The APOGEE-2 Survey of the Orion Star-forming Complex. II. Six-dimensional Structure 2018AJ....156...84K
    A Chemical and Kinematical Analysis of the Intermediate-age Open Cluster IC 166 from APOGEE and Gaia DR2 2018AJ....156...94S
    APOGEE Data Releases 13 and 14: Data and Analysis 2018AJ....156..125H
    APOGEE Data Releases 13 and 14: Stellar Parameter and Abundance Comparisons with Independent Analyses 2018AJ....156..126J
    The Open Cluster Chemical Abundances and Mapping Survey. II. Precision Cluster Abundances for APOGEE Using SDSS DR14 2018AJ....156..142D
    The Double Dust Envelopes of R Coronae Borealis Stars 2018AJ....156..148M
    Evolved stars in the Local Group galaxies - II. AGB, RSG stars, and dust production in IC10 2018MNRAS.479.5035D
    Self-enrichment in globular clusters: the extreme He-rich populationof NGC 2808 2018MNRAS.479.5325D
    A new linelist for the A3Π-X3Σ- transition of the NH free radical 2018JQSRT.217...29F
    A new line list for the A2Σ+ -X2 Π electronic transition of OH 2018JQSRT.217..416Y
    Forty-four New and Known M-dwarf Multiples in the SDSS-III/APOGEE M-dwarf Ancillary Science Sample 2018AJ....156...45S
    Kepler-503b: An Object at the Hydrogen Burning Mass Limit Orbiting a Subgiant Star 2018ApJ...861L...4C
    Binary Companions of Evolved Stars in APOGEE DR14: Search Method and Catalog of ∼5000 Companions 2018AJ....156...18P
    Stellar and Planetary Characterization of the Ross 128 Exoplanetary System from APOGEE Spectra 2018ApJ...860L..15S
    Signatures of the Galactic bar on stellar kinematics unveiled by APOGEE 2018MNRAS.478.1231P
    Chemical Composition of Two Bright, Extremely Metal-poor Stars from the SDSS MARVELS Pre-survey 2018ApJ...859..114B
    Disk-like Chemistry of the Triangulum-Andromeda Overdensity as Seen by APOGEE 2018ApJ...859L...8H
    Age-resolved chemistry of red giants in the solar neighbourhood 2018MNRAS.477.2326F
    The Fourteenth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the Extended Baryon Oscillation Spectroscopic Survey and from the Second Phase of the Apache Point Observatory Galactic Evolution Experiment 2018ApJS..235...42A
    Heavy-element yields and abundances of asymptotic giant branch models with a Small Magellanic Cloud metallicity 2018MNRAS.477..421K
    Magnesium isotopes: a tool to understand self-enrichment in globular clusters 2018MNRAS.477..438V
    Chemical Abundances of Main-sequence, Turnoff, Subgiant, and Red Giant Stars from APOGEE Spectra. I. Signatures of Diffusion in the Open Cluster M67 2018ApJ...857...14S
    StarHorse: a Bayesian tool for determining stellar masses, ages, distances, and extinctions for field stars 2018MNRAS.476.2556Q
    The Metal-poor non-Sagittarius (?) Globular Cluster NGC 5053: Orbit and Mg, Al, and Si Abundances 2018ApJ...855...38T
    Massive Stars in the SDSS-IV/APOGEE SURVEY. I. OB Stars 2018ApJ...855...68R
    GTC/CanariCam Mid-IR Imaging of the Fullerene-rich Planetary Nebula IC 418: Searching for the Spatial Distribution of Fullerene-like Molecules 2018AJ....155..105D
    A view of the H-band light-element chemical patterns in globular clusters under the AGB self-enrichment scenario 2018MNRAS.475.3098D
    Submerged carbon arc in liquid benzene: GC-MS analysis of the products 2017FNCN...25..576C
    Gas and dust from solar metallicity AGB stars 2018MNRAS.475.2282V
    280 one-opposition near-Earth asteroids recovered by the EURONEAR with the Isaac Newton Telescope 2018A&A...609A.105V
    A photometric study of globular clusters observed by the APOGEE survey 2018MNRAS.475.1633M

    Related talks

    No related talks were found.

    Related conferences

    No related conferences were found.