Start year
1986
Organizational Unit
Organizing institutions
Grants related:
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.
Members
Principal investigator
Domingo Aníbal
García Hernández
Project staff
Arturo
Manchado Torres
Thomas
Masseron
Olga María
Zamora Sánchez
LUCIO
CRIVELLARI
Collaborators
Dr.
P. García Lario
Dr.
G. García Segura
Dr.
L. Stanghellini
Dr.
E. Villaver
Carlos
Allende Prieto
Jorge
García Rojas
Dr.
B. Plez
Dr.
A. Karakas
Dr.
M. Lugaro
Dr.
D. Lambert
Dr.
P. Ventura
Dr.
F. Cataldo
Dr.
Andres Yague
Dr.
Sun Kwok
Dr.
R. Szczerba
Dr.
J.M. Trigo Rodríguez
Dr.
K. Rao
S. Sadjadi
M. Manteiga
C. Dafonte
R. Santoveña
L. Bianchi
Sz. Mészáros
S. Cristallo
L. Piersanti
Results
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.
Scientific activity
Related publications
-
12C/13C isotopic ratios in red-giant stars of the open cluster NGC 6791Carbon isotope ratios, along with carbon and nitrogen abundances, are derived in a sample of 11 red-giant members of one of the most metal-rich clusters in the Milky Way, NGC 6791. The selected red-giants have a mean metallicity and standard deviation of [Fe/H] = +0.39 ± 0.06 (Cunha et al. 2015). We used high-resolution H-band spectra obtained bySzigeti, L. et al.
Advertised on:
32018 -
The interaction of the halo around the butterfly planetary nebula NGC 650-1 with the interstellar mediumWith its bright and wide equatorial waist seen almost edge-on (`the butterfly body') and the faint and broad bipolar extensions (`the butterfly wings'), NGC 650-1 is the archetypical example of bipolar planetary nebula (PN) with butterfly morphology. We present here deep high-resolution broad- and narrow-band optical images that expose the rich andRamos-Larios, G. et al.
Advertised on:
32018 -
The First APOKASC Catalog of Kepler Dwarf and Subgiant StarsWe present the first APOKASC catalog of spectroscopic and asteroseismic data for dwarfs and subgiants. Asteroseismic data for our sample of 415 objects have been obtained by the Kepler mission in short (58.5 s) cadence, and light curves span from 30 up to more than 1000 days. The spectroscopic parameters are based on spectra taken as part of theSerenelli, A. et al.
Advertised on:
122017 -
The 13th Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the SDSS-IV Survey Mapping Nearby Galaxies at Apache Point ObservatoryThe fourth generation of the Sloan Digital Sky Survey (SDSS-IV) began observations in 2014 July. It pursues three core programs: the Apache Point Observatory Galactic Evolution Experiment 2 (APOGEE-2), Mapping Nearby Galaxies at APO (MaNGA), and the Extended Baryon Oscillation Spectroscopic Survey (eBOSS). As well as its core program, eBOSSAlbareti, F. D. et al.
Advertised on:
122017 -
C70 Fullerene charge-transfer interaction with alkylnaphthalenes, pinenes, and a dieneAlkylnaphthalenes are not able to form Diels-Alder adducts with C70 fullerene but selected alkylnaphthalenes are able to yield weak charge-transfer complexes (CTC) with C70. More in detail, 1-methylnaphthalene, 2-ethylnaphthalene, and pure naphthalene are not able to produce neither Diels-Alder adducts with C70 fullerene nor CTC. Instead, 1,4García-Hernández, D. A. et al.
Advertised on:
52017 -
Charge-transfer interaction between C60 fullerene and alkylnaphthalenesA series of alkylnaphthalenes, namely 1,4-dimethylnaphthalene, 2,6-diethylnaphthalene, 2-ethylnaphthalene and pure naphthalene are not able to form Diels-Alder adducts with C60 fullerene but produce a series of 1:1 charge-transfer complexes (CTC) where the aromatic compounds act as donor and C60 as acceptor. The spectrophotometric analysis of theseGarcía-Hernández, D. A. et al.
Advertised on:
12017 -
Target Selection for the SDSS-IV APOGEE-2 SurveyAPOGEE-2 is a high-resolution, near-infrared spectroscopic survey observing ∼3 × 105 stars across the entire sky. It is the successor to APOGEE and is part of the Sloan Digital Sky Survey IV (SDSS-IV). APOGEE-2 is expanding on APOGEE’s goals of addressing critical questions of stellar astrophysics, stellar populations, and Galactic chemodynamicalZasowski, G. et al.
Advertised on:
112017 -
Rubidium and zirconium abundances in massive Galactic asymptotic giant branch stars revisitedContext. Luminous Galactic OH/IR stars have been identified as massive (>4-5 M⊙) asymptotic giant branch (AGB) stars experiencing hot bottom burning and Li production. Their Rb abundances and [Rb/Zr] ratios, as derived from classical hydrostatic model atmospheres, are significantly higher than predictions from AGB nucleosynthesis models, posing aPérez-Mesa, V. et al.
Advertised on:
92017 -
Adding the s-Process Element Cerium to the APOGEE Survey: Identification and Characterization of Ce ii Lines in the H-band Spectral WindowNine Ce ii lines have been identified and characterized within the spectral window observed by the Apache Point Observatory Galactic Evolution Experiment (APOGEE) survey (between λ1.51 and 1.69 μm). At solar metallicities, cerium is an element that is produced predominantly as a result of the slow capture of neutrons (the s-process) duringCunha, K.a et al.
Advertised on:
82017 -
APOGEE Chemical Abundances of the Sagittarius Dwarf GalaxyThe Apache Point Observatory Galactic Evolution Experiment provides the opportunity of measuring elemental abundances for C, N, O, Na, Mg, Al, Si, P, K, Ca, V, Cr, Mn, Fe, Co, and Ni in vast numbers of stars. We analyze thechemical-abundance patterns of these elements for 158 red giant stars belonging to the Sagittarius dwarf galaxy (Sgr). This isHasselquist, S. et al.
Advertised on:
82017 -
The Apache Point Observatory Galactic Evolution Experiment (APOGEE)The Apache Point Observatory Galactic Evolution Experiment (APOGEE), one of the programs in the Sloan Digital Sky Survey III (SDSS-III), has now completed its systematic, homogeneous spectroscopic survey sampling all major populations of the Milky Way. After a three-year observing campaign on the Sloan 2.5 m Telescope, APOGEE has collected a halfMajewski, S. R. et al.
Advertised on:
92017 -
Atypical Mg-poor Milky Way Field Stars with Globular Cluster Second-generation-like Chemical PatternsWe report the peculiar chemical abundance patterns of 11 atypical Milky Way (MW) field red giant stars observed by the Apache Point Observatory Galactic Evolution Experiment (APOGEE). These atypical giants exhibit strong Al and N enhancements accompanied by C and Mg depletions, strikingly similar to those observed in the so-called second-generationFernández-Trincado, J. G. et al.
Advertised on:
92017 -
The evolution of Galactic planetary nebula progenitors through the comparison of their nebular abundances with AGB yieldsWe study the chemical abundances of a wide sample of 142 Galactic planetary nebulae (PNe) with good-quality observations, for which the abundances have been derived more or less homogeneously, thus allowing a reasonable comparison with stellar models. The goal is the determination of mass, chemical composition and formation epoch of theirGarcía-Hernández, D. A. et al.
Advertised on:
112017 -
Sloan Digital Sky Survey IV: Mapping the Milky Way, Nearby Galaxies, and the Distant UniverseWe describe the Sloan Digital Sky Survey IV (SDSS-IV), a project encompassing three major spectroscopic programs. The Apache Point Observatory Galactic Evolution Experiment 2 (APOGEE-2) is observing hundreds of thousands of Milky Way stars at high resolution and high signal-to-noise ratios in the near-infrared. The Mapping Nearby Galaxies at ApacheMao, Shude et al.
Advertised on:
72017 -
The Correlation between Mixing Length and Metallicity on the Giant Branch: Implications for Ages in the Gaia EraIn the updated APOGEE-Kepler catalog, we have asteroseismic and spectroscopic data for over 3000 first ascent red giants. Given the size and accuracy of this sample, these data offer an unprecedented test of the accuracy of stellar models on the post-main-sequence. When we compare these data to theoretical predictions, we find a metallicityTayar, Jamie et al.
Advertised on:
52017 -
Asymptotic giant branch and super-asymptotic giant branch stars: modelling dust production at solar metallicityWe present dust yields for asymptotic giant branch (AGB) and super-asymptotic giant branch (SAGB) stars of solar metallicity. Stars with initial mass 1.5 M⊙ ≤ Mini ≤ 3 M⊙ reach the carbon star stage during the AGB phase and produce mainly solid carbon and SiC. The size and the amount of the carbon particles formed follows a positive trend with theDell'Agli, F. et al.
Advertised on:
62017 -
Red giants observed by CoRoT and APOGEE: The evolution of the Milky Way's radial metallicity gradientUsing combined asteroseismic and spectroscopic observations of 418 red-giant stars close to the Galactic disc plane (6 kpc RGal ≲ 13 kpc, | ZGal| 0.3 kpc), we measure the age dependence of the radial metallicity distribution in the Milky Way's thin disc over cosmic time. The slope of the radial iron gradient of the young red-giant population (-0Anders, F. et al.
Advertised on:
32017 -
Two groups of red giants with distinct chemical abundances in the bulge globular cluster NGC 6553 through the eyes of APOGEEMultiple populations revealed in globular clusters (GCs) are important windows to the formation and evolution of these stellar systems. The metal-rich GCs in the Galactic bulge are an indispensable part of this picture, but the high optical extinction in this region has prevented extensive research. In this work, we use the high-resolution nearTang, B. et al.
Advertised on:
22017 -
Chemical tagging with APOGEE: discovery of a large population of N-rich stars in the inner GalaxyFormation of globular clusters (GCs), the Galactic bulge, or galaxy bulges in general is an important unsolved problem in Galactic astronomy. Homogeneous infrared observations of large samples of stars belonging to GCs and the Galactic bulge field are one of the best ways to study these problems. We report the discovery by APOGEE (Apache PointSchiavon, R. P. et al.
Advertised on:
22017 -
Chemical Abundances of M-dwarfs from the APOGEE Survey. I. The Exoplanet Hosting Stars Kepler-138 and Kepler-186We report the first detailed chemical abundance analysis of the exoplanet-hosting M-dwarf stars Kepler-138 and Kepler-186 from the analysis of high-resolution (R ∼ 22,500) H-band spectra from the SDSS-IV–APOGEE survey. Chemical abundances of 13 elements—C, O, Na, Mg, Al, Si, K, Ca, Ti, V, Cr, Mn, and Fe—are extracted from the APOGEE spectra ofSouto, D. et al.
Advertised on:
22017
