A5065642219- Stellar, planetary, and galactic studies
- Astronomy and Astrophysical Research
- Astrophysics and Star Formation Studies
- Astro and Planetary Science
- Gamma-ray bursts and supernovae
- Galaxies: Formation, Evolution, Phenomena
- Astronomical Observations and Instrumentation
- Nuclear physics research studies
- Nuclear Physics and Applications
- Astronomical and nuclear sciences
- Spectroscopy and Laser Applications
- Adaptive optics and wavefront sensing
- History and Developments in Astronomy
- Cosmology and Gravitation Theories
- Atmospheric Ozone and Climate
- Geophysics and Gravity Measurements
- High-pressure geophysics and materials
- Pulsars and Gravitational Waves Research
- Astrophysical Phenomena and Observations
- Dark Matter and Cosmic Phenomena
- Atmospheric and Environmental Gas Dynamics
- Nuclear reactor physics and engineering
- Atomic and Subatomic Physics Research
- Calibration and Measurement Techniques
- Impact of Light on Environment and Health
University of Padua
2016-2025
Istituto Nazionale di Fisica Nucleare, Sezione di Padova
2016-2025
Osservatorio Astronomico di Padova
2015-2024
Istituto Nazionale di Fisica Nucleare, Galileo Galilei Institute for Theoretical Physics
2014-2023
Space Telescope Science Institute
2019
HUN-REN Institute for Nuclear Research
2019
Institut d'Astrophysique de Paris
2011
European Southern Observatory
2011
Vrije Universiteit Brussel
2011
Max Planck Institute for Astrophysics
1999-2001
We present the updated version of code used to compute stellar evolutionary tracks in Padova. It is result a thorough revision major input physics, together with inclusion pre-main sequence phase, not our previous releases models. Another innovative aspect possibility promptly generating accurate opacity tables fully consistent any selected initial chemical composition, by coupling Opacity Project At Livermore (OPAL) data at high temperatures molecular opacities computed æsopus code. In this...
We present a large set of theoretical isochrones, whose distinctive features mostly reside on the greatly improved treatment thermally pulsing asymptotic giant branch (TP-AGB) phase. Essentially, we have coupled TP-AGB tracks described in Paper I, at their stages pre-flash quiescent H-shell burning, with evolutionary for previous phases from Girardi et al. (2000). Theoretical isochrones any intermediate value age and metallicity are then derived by interpolation grids. take care that keep,...
We introduce a new generation of PARSEC-COLIBRI stellar isochrones that include detailed treatment the thermally-pulsing asymptotic giant branch (TP-AGB) phase, and covering wide range initial metallicities (0.0001<Zi<0.06). Compared to previous releases, main novelties improvements are: use TP-AGB tracks related atmosphere models spectra for M C-type stars; inclusion surface H+He+CNO abundances in isochrone tables, accounting effects diffusion, dredge-up episodes hot-bottom burning;...
Many stellar models present difficulties in reproducing basic observational relations of very low mass stars (VLMS), including the mass--radius relation and optical colour--magnitudes cool dwarfs. Here, we improve PARSEC on these points. We implement T--tau from PHOENIX BT-Settl model atmospheres as outer boundary conditions code, finding that this change alone reduces discrepancy 8 to 5 per cent. compare with multi--band photometry clusters Praesepe M67, showing use clearly improves...
We complement the parsec data base of stellar evolutionary tracks with new models massive stars, from pre-main-sequence phase to central carbon ignition. consider a broad range metallicities, 0.0001 ≤ Z 0.04 and initial masses up Mini = 350 M⊙. The main difference respect our previous stars is adoption recent formalizm accounting for mass-loss enhancement when ratio Eddington luminosity, Γe, approaches unity. With this formalizm, are able reproduce Humphreys–Davidson limit observed in...
We extend the {\sl\,PARSEC} library of stellar evolutionary tracks by computing new models massive stars, from 14\Msun to 350\Msun. The input physics is same used in {\sl\,PARSEC}~V1.1 version, but for mass-loss rate which included considering most recent updates literature. focus on low metallicity, $Z$=0.001 and $Z$=0.004, metal poor dwarf irregular star forming galaxies, Sextans A, WLM NCG6822, provide simple powerful workbenches. reproduce fairly well observed CMDs colour distributions...
Context. In many astrophysical contexts, the helium content of stars may differ significantly from those usually assumed in evolutionary calculations.
We present new synthetic models of the TP-AGB evolution. They are computed for 7 values initial metal content (Z from 0.0001 to 0.03) and masses between 0.5 5.0 , thus extending low- intermediate-mass tracks Girardi et al. (2000) beginning post-AGB phase. The calculations performed by means a code that incorporates many recent improvements, among which we mention: (1) use detailed revised analytical relations describe evolution quiescent luminosity, inter-pulse period, third dredge-up, hot...
In an attempt to constrain evolutionary models of the asymptotic giant branch (AGB) phase at limit low masses and metallicities, we have examined luminosity functions number ratio between AGB red (RGB) stars from a sample resolved galaxies ACS Nearby Galaxy Survey Treasury (ANGST). This database provides HST optical photometry together with maps completeness, photometric errors, star formation histories for dozens within 4 Mpc. We select 12 characterized by predominantly metal-poor...
We present the COLIBRI code for computing evolution of stars along TP-AGB phase. Compared to purely synthetic codes, relaxes a significant part their analytic formalism in favour detailed physics applied complete envelope model, which stellar structure equations are integrated from atmosphere down bottom hydrogen-burning shell. This allows predict self-consistently: (i) effective temperature, and more generally convective structures, correctly coupled changes surface chemical abundances gas...
We describe the content and properties of UV source catalogs from GALEX’s All-Sky Imaging Survey (AIS, 5σ depth ≈19.9(FUV)/20.8(NUV) mag, in AB system) Medium-depth (MIS, ≈22.6(FUV)/22.7(NUV) mag), constructed by Bianchi L., et al.: Mon. Not. R. Astron. Soc. (2010, press). The contain 65.3/12.6 million (AIS/MIS) unique sources with photometric error NUV less than 0.5 over 21 435(AIS)/1579(MIS) square degrees. Matched optical data GSC-II provide additional B, R, I photometry for brightest...
The thermally-pulsing asymptotic giant branch (TP-AGB) experienced by low- and intermediate-mass stars is one of the most uncertain phases stellar evolution models need to be calibrated with aid observations. To this purpose, we couple high-quality observations resolved in Small Magellanic Cloud (SMC) detailed population synthesis simulations computed TRILEGAL code. strength our approach relies on spatially-resolved star formation history SMC, derived from deep near-infrared photometry VISTA...
We present a new comprehensive collection of stellar evolutionary tracks and isochrones for rotating low- intermediate-mass stars assembled with the updated version PARSEC V2.0. This includes our recent calibration extra mixing from overshooting rotation, as well several improvements in nuclear reaction network, treatment convective zones, mass loss other physical input parameters. The initial models covers range 0.09 $M_\odot$ to 14 $M_\odot$, six sets metallicity, Z=0.004 Z=0.017. Rotation...
Abstract We present NIRCam and NIRISS modules for DOLPHOT, a widely used crowded-field stellar photometry package. describe details of the including pixel masking, astrometric alignment, star finding, photometry, catalog creation, artificial tests. tested these using images M92 (a Milky Way globular cluster), Draco II (an ultrafaint dwarf galaxy), Wolf–Lundmark–Mellote star-forming galaxy). DOLPHOT’s is highly precise, color–magnitude diagrams are deeper have better definition than...
We extend our theoretical computations for low-mass stars to intermediate-mass and massive stars, which few databases exist in the literature. Evolutionary tracks isochrones are computed from 2.50 20 solar masses agrid of 37 chemical compositions with metal content Z between 0.0001 0.070 helium Y 0.23 0.40. Synthetic TP-AGB models allow stellar be extended until end thermal pulses along AGB. provide software tools bidimensional interpolation (in Z) isochrones. present scaled-solar abundances...
We introduce a new tool – ÆSOPUS: Accurate Equation of State and OPacity Utility Software for computing the equation state Rosseland mean (RM) opacities matter in ideal gas phase. Results are given as function one pair variables, (i.e. temperature <i>T<i/> range , parameter ), arbitrary chemical mixture. The chemistry is presently solved about 800 species, consisting almost 300 atomic 500 molecular species. account many continuum discrete sources, including opacities, absorption bands,...
We study the spectroscopic and photometric properties of carbon stars. In first paper this series we focus on objects that can be described by hydrostatic models neglecting dynamical phenomena like pulsation mass loss. As a consequence, reddening due to circumstellar dust is not included. Our results are collected in database, which used conjunction with stellar evolution population synthesis calculations involving AGB. have computed grid 746 spherically symmetric COMARCS atmospheres...
We present color-magnitude diagram analysis of deep Hubble Space Telescope imaging a mass-limited sample 18 intermediate-age (1 - 2 Gyr old) star clusters in the Magellanic Clouds, including 8 for which new data was obtained. find that ${\it all}$ our feature extended main sequence turnoff (eMSTO) regions are wider than can be accounted by simple stellar population (including unresolved binary stars). FWHM widths MSTOs indicate age spreads 200-550 Myr. evaluate dynamical evolution with and...
We present the dust ejecta of new stellar models for thermally pulsing asymptotic giant branch (TP-AGB) phase computed with colibri code. use a formalism growth coupled stationary wind both M- and C-stars. In original version this formalism, most efficient destruction process silicate in M-giants is chemisputtering by H2 molecules. For these stars, we find that grains can only form at relatively large radial distances (r ∼ 5R*), where they cannot be efficiently accelerated, agreement other...
Pair-instability (PI) is expected to open a gap in the mass spectrum of black holes (BHs) between $\approx{}40-65$ M$_\odot$ and $\approx{}120$ M$_\odot$. The existence currently being challenged by detection GW190521, with primary component $85^{+21}_{-14}$ M$_{\odot}$. Here, we investigate main uncertainties on PI gap: $^{12}$C($\alpha$, $\gamma$)$^{16}$O reaction rate H-rich envelope collapse. With standard rate, lower edge can be 70 if allow for collapse residual at metallicity...