A5048859670- Stellar, planetary, and galactic studies
- Astronomy and Astrophysical Research
- Astrophysics and Star Formation Studies
- Astro and Planetary Science
- History and Developments in Astronomy
- Galaxies: Formation, Evolution, Phenomena
- Isotope Analysis in Ecology
- Gamma-ray bursts and supernovae
- Adaptive optics and wavefront sensing
- Astronomical Observations and Instrumentation
- Geology and Paleoclimatology Research
- Geomagnetism and Paleomagnetism Studies
- Astronomical and nuclear sciences
- X-ray Spectroscopy and Fluorescence Analysis
- Spectroscopy and Laser Applications
- Phonetics and Phonology Research
- Remote Sensing in Agriculture
- Spectroscopy and Chemometric Analyses
- Spectroscopy Techniques in Biomedical and Chemical Research
- Archaeological and Geological Studies
- Pigment Synthesis and Properties
- Impact of Light on Environment and Health
Osservatorio Astronomico di Padova
2021-2025
University of Padua
2021-2024
In the past years, we have undertaken an extensive investigation of LMC and SMC star clusters based on HST data. We present photometry astrometry stars in 101 fields observed with WFC/ACS, UVIS/WFC3 NIR/WFC3 cameras. These comprise 113 clusters. provide differential-reddening maps illustrate various scientific outcomes that arise from early inspection photometric catalogs. particular, new insights extended main-sequence turn-off (eMSTO) phenomenon: i) detected eMSTOs two clusters, KMHK361...
Binary stars play a crucial role in our understanding of the formation and evolution star clusters their stellar populations. We use Gaia Data Release 3 to homogeneously analyze 78 Galactic open unresolved binary systems they host, each composed two main sequence (MS) stars. first investigated structural parameters these clusters, such as core radius central density, determined cluster mass function (MF) total by interpolating density profile cluster. measured fraction binaries with large...
Disentangling distinct stellar populations along the red-giant branches (RGBs) of Globular Clusters (GCs) is possible by using pseudo two-color diagram dubbed chromosome map (ChM). One most intriguing findings that so-called first-generation (1G) stars, characterized same chemical composition their natal cloud, exhibit extended sequences in ChM. Unresolved binaries and internal variations helium or metallicity have been suggested to explain this phenomenon. Here, we derive high-precision...
Abstract James Webb Space Telescope (JWST) observations have been demonstrated to be efficient in detecting multiple stellar populations globular clusters (GCs) the low-mass regime of M dwarfs. We present an overview, and first results, different projects that can explored by using JWST gathered under program GO2560 for 47 Tucanae, entirely devoted investigation very-low-mass stars, which includes spectroscopic data faintest GC stars spectra are available. Our color–magnitude diagram (CMD)...
Abstract The pseudo two-color diagram, known as chromosome map (ChM), is a valuable tool for identifying globular clusters (GCs), which consist of single or multiple stellar populations (MPs). Recent surveys Galactic GCs using ChMs have provided stringent observational constraints on the formation and their populations. However, these primarily focused at moderate distances from center composed MPs. In this paper, we present first detailed study composition four in outer halo Milky Way: Arp...
ABSTRACT We present a detailed analysis of the internal dynamics multiple stellar populations (MPs) in 28 Galactic globular clusters (GCs) across wide field view, extending from innermost regions to clusters’ outskirts. Using astrophotometric catalogues ground-based observations, Gaia and Hubble Space Telescope (HST), we identify first- (1P) second-population (2P) stars, study MPs using high-precision DR3 HST proper motions. Our results reveal that while 1P transitions isotropy slight...
We use images collected with the near-infrared camera (NIRCam) on board James Webb Space Telescope and Hubble (HST) to investigate multiple populations at bottom of main sequence (MS) 47 Tucanae. The F115W vs. F115W-F322W2 CMD from NIRCam shows that, below knee, MS stars span a wide color range, where majority M-dwarfs exhibit blue colors, tail are distributed toward red. A similar pattern is observed F160W F110W-F160W HST, also visible in optical F606W F606W-F814W CMD. narrow faint masses...
ABSTRACT The presence of differential reddening in the direction Galactic globular clusters (GCs) has proven to be a serious limitation traditional colour–magnitude diagram (CMD) analysis. Here, we estimate local variations 56 GCs. To do that, use public catalogues derived as part Hubble Space Telescope UV Legacy Survey GCs, which include photometry F275W, F336W, F438W, F606W, and F814W filters. We corrected for found that 21 out GCs adopted correction procedure significantly improved CMDs....
Recent work on metal-intermediate globular clusters (GCs) with [Fe/H]=$-1.5$ and $-0.75$ has illustrated the theoretical behavior of multiple populations in photometric diagrams obtained James Webb Space Telescope (JWST). These results are confirmed by observations among M-dwarfs 47 Tucanae. Here, we explore metal-poor GCs [Fe/H]=$-$2.3. We take advantage synthetic spectra isochrones that account for chemical composition to identify separate distinct stellar GCs. derived high-precision...
ABSTRACT M 22 (NGC 6656) is a chemically complex globular cluster-like system reported to harbour heavy element abundance variations. However, the extent of these variations and origin this cluster still debated. In work, we investigate chemical in-homogeneity using differential line-by-line analysis high-quality (R = 110 000, S/N 300 per pixel at 514 nm) VLT/UVES spectra six carefully chosen red giant branch stars. By achieving uncertainties as low ∼0.01 dex (∼2 cent), high precision data...
Hubble Space Telescope (HST) photometry is providing an extensive analysis of globular clusters (GCs). In particular, the pseudo two-colour diagram dubbed 'chromosome map (ChM)' allowed to detect and characterize their multiple populations with unprecedented detail. The main limitation these studies small field view HST, which makes it challenging investigate some important aspects populations, such as spatial distributions internal kinematics in outermost cluster regions. To overcome this...
Recent work has shown that NIR Hubble Space Telescope (HST) photometry allows us to disentangle multiple populations (MPs) among M dwarfs of globular clusters (GCs) and investigate this phenomenon in very low-mass (VLM) stars. Here, we present the color-magnitude diagrams (CMDs) nine GCs open cluster NGC 6791 F110W F160W bands HST, showing main sequences (MSs) below knee are either broadened or split thus providing evidence MPs VLM In contrast, MS is consistent with a single population. The...
We investigate the behavior of multiple stellar populations in globular clusters (GCs) using photometric diagrams constructed with Euclid photometry. By employing synthetic spectra and isochrones that incorporate chemical differences between first-population (1P) stars, resembling field second-population (2P) enriched helium nitrogen but depleted carbon oxygen, we identify, from a theoretical perspective, color-magnitude chromosome maps most effective at distinguishing these within GCs....
Wide-field photometry of Galactic globular clusters (GCs) has been investigated to overcome limitations from the small field view Hubble Space Telescope in study multiple populations. In particular, 'chromosome maps' (ChMs) built with ground-based were constructed identify first and second generation stars (1G 2G) over wide-field view. The ChMs allow us derive fraction distinct populations an analyzed We present here radial distribution 2G 29 GCs. distributions show that all GCs either have...
Recent work with JWST has demonstrated its capability to identify and chemically characterize multiple populations in globular clusters down the H-burning limit. In this study, we explore kinematics of cluster 47 Tucanae by combining data from JWST, HST, Gaia. We analyzed velocity dispersion anisotropy profiles center out $\sim$10$R_h$. Our findings indicate that while 1G stars are isotropic, 2G significantly radially anisotropic. These results align predictions simulations dynamical...
The morphology of the Horizontal Branch (HB) in Globular Clusters (GC) is among early evidences that they contain multiple populations stars. Indeed, location each star along HB depends both on its initial helium content (Y) and global average mass loss red giant branch ($\mu$). In most GCs, it generally straightforward to analyse first stellar population (standard Y), extreme one (largest while more tricky look at "intermediate" (mildly enhanced Y). this work, we do for GCs NGC6752 NGC2808;...
Abstract Wide-field photometry of Galactic globular clusters (GCs) has been investigated to overcome limitations from the small field view Hubble Space Telescope in study multiple populations. In particular, “chromosome maps” (ChMs) built with ground-based were constructed identify first- and second-generation (1G 2G) stars over wide view. The ChMs allow us derive fraction distinct populations an analyzed We present here radial distribution 2G 29 GCs. distributions show that all GCs have...
The morphology of the horizontal branch (HB) in globular clusters (GCs) offers some early evidence that they contain multiple populations stars. Indeed, location each star along HB depends both on its initial helium content (Y) and global average mass loss red giant (μ) In most GCs it is generally straightforward to analyse first stellar population (standard Y) extreme one (largest Y), while more tricky look at 'intermediate' (mildly enhanced Y). this work, we consider segement for NGC,6752...
We investigate the behavior of multiple stellar populations in globular clusters (GCs) using photometric diagrams constructed with Euclid photometry. By employing synthetic spectra and isochrones that incorporate chemical differences between first-population (1P) stars (resembling field stars) second-population (2P) (enriched helium nitrogen, but depleted carbon oxygen) we have identified, from a theoretical perspective, color-magnitude chromosome maps most effective at distinguishing these...
Globular clusters (GCs) are known to host distinct stellar populations, characterized by different chemical compositions. Despite extensive research, the origin of these populations remains elusive. According many formation scenarios, second population (2P) originated within a compact and denser region embedded in more extended first (1P) system. As result, 2P binaries should be disrupted at larger rate than 1P binaries. For this reason, binary systems offer valuable insight into...
Our understanding of multiple populations in globular clusters (GCs) largely comes from photometry and spectroscopy. Appropriate photometric diagrams are able to disentangle first second (1P 2P, respectively), with 1P having chemical signatures similar field stars 2P showing unique light-element variations. Spectroscopy enables detailed analysis abundances these populations. We combined multi-band extensive spectroscopic data investigate the composition across 38 GCs, yielding a abundance...
Recent work with JWST has demonstrated its capability to identify and chemically characterize multiple populations in globular clusters down the H-burning limit. In this study, we explore kinematics of cluster 47,Tucanae by combining data from HST Gaia, ground-based telescopes. We analyzed velocity dispersion anisotropy profiles center out ∼10R_h. Our findings indicate that while first population (1G) stars' motions are isotropic, second (2G) significantly radially anisotropic. These results...
Almost all globular clusters (GCs) contain multiple stellar populations consisting of stars with varying helium and light-element abundances. These include first-population stars, which exhibit similar chemical compositions as halo-field comparable Fe/H second-population characterized by higher nitrogen abundances along reduced levels oxygen carbon. Nowadays, one the most intriguing open questions about GCs pertains to formation evolution their populations. Recent works based on N-body...
Abstract The “chromosome maps” (ChMs) of globular clusters (GCs) have revealed that these ancient structures are inhomogeneous in metallicity various ways and different natures. Type II GCs generally display larger variations, sometimes coupled with slow neutron-capture ( s ) element enrichments on the ChMs redder sequences, which been interpreted as due to multiple generations stars. On other hand, most first populations (1P) form large ranges Δ F275W,F814W values, pointing toward a not...
The origin of young star clusters represents a major challenge for modern stellar astrophysics. While rotation partially explains the colour spread observed along main-sequence turn-offs, i.e. where stars leave after exhaustion hydrogen in their core, and multiple main sequences colour-magnitude diagrams systems younger than approximately 2 Gyr, it appears that an age difference may still be required to fulfill observational constraints. Here we introduce alternative approach exploits...