A. Garofalo
A5027765936- Stellar, planetary, and galactic studies
- Astronomy and Astrophysical Research
- Gamma-ray bursts and supernovae
- Astro and Planetary Science
- Astronomical Observations and Instrumentation
- Astrophysics and Star Formation Studies
- Galaxies: Formation, Evolution, Phenomena
- Scientific Research and Discoveries
- Distributed and Parallel Computing Systems
- Geophysics and Gravity Measurements
- Geomagnetism and Paleomagnetism Studies
- History and Developments in Astronomy
- Geological Modeling and Analysis
- BIM and Construction Integration
- Planetary Science and Exploration
- Time Series Analysis and Forecasting
- Astrophysical Phenomena and Observations
- Complex Systems and Time Series Analysis
- Synthesis and Reactions of Organic Compounds
- Particle Detector Development and Performance
- Click Chemistry and Applications
- Calibration and Measurement Techniques
- Cosmology and Gravitation Theories
- Earth Systems and Cosmic Evolution
- 3D Modeling in Geospatial Applications
Osservatorio di Astrofisica e Scienza dello Spazio
2018-2024
Istituto di Astrofisica Spaziale e Fisica Cosmica di Bologna
2018-2024
Institut de Physique et Chimie des Matériaux de Strasbourg
2017-2022
National Institute for Astrophysics
2013-2021
University of Bologna
2013-2021
Osservatorio astronomico di Bologna
2013-2018
Max Planck Society
2018
Carnegie Observatories
2015
Context. The third Gaia data release is published in two stages. early part, EDR3, gives very precise astrometric and photometric properties for nearly billion sources together with seven million radial velocities from DR2. full release, DR3, will add velocities, spectra, light curves, astrophysical parameters a large subset of the sources, as well orbits solar system objects. Aims. Before publication catalogue, many different items have undergone dedicated validation processes. goal this...
The Gaia second Data Release (DR2) presents a first mapping of full-sky RR Lyrae stars and Cepheids observed by the spacecraft during initial 22 months science operations. Specific Object Study (SOS) pipeline, developed to validate fully characterise (SOS Cep&RRL) Gaia, has been presented in documentation papers accompanying Release. Here we describe how SOS pipeline was modified allow for processing multiband (G, G_BP G_RP) time series photometry all-sky candidate variables produce specific...
Context. Gaia has been in operations since 2014. The third data release expands from the early (EDR3) 2020 by providing 34 months of multi-epoch observations that allowed us to probe, characterise and classify systematically celestial variable phenomena. Aims. We present a summary variability processing analysis photometric spectroscopic time series 1.8 billion sources done for DR3. Methods. used statistical Machine Learning methods sources. Training sets were built global revision major...
Gaia DR3 contains 1.8 billion sources with G-band photometry, 1.5 of which BP and RP complemented by positions on the sky, parallax, proper motion. The median number field-of-view transits in three photometric bands is between 40 44 measurements per source covers 34 months data collection. We pursue a classification Galactic extra-galactic objects that are detected as variable across whole sky. Supervised machine learning (eXtreme Gradient Boosting Random Forest) was employed to generate...
We present an overview of the Carnegie-Chicago Hubble Program, ongoing program to obtain a 3 per cent measurement constant using alternative methods traditional Cepheid distance scale. aim establish completely independent route RR Lyrae variables, tip red giant branch (TRGB), and Type Ia supernovae (SNe Ia). This ladder can be applied galaxies any Type, inclination, and, utilizing old stars in low density environments, is robust degenerate effects metallicity interstellar extinction. Given...
We present results from the analysis of 401 RR Lyrae stars (RRLs) belonging to field Milky Way (MW). For a fraction them multi-band ($V$, $K_{\rm s}$, $W1$) photometry, metal abundances, extinction values and pulsation periods are available in literature accurate trigonometric parallaxes measured by Gaia mission alongside $G$-band time-series photometry have become with second data release (DR2) on 2018 April 25. Using Bayesian fitting approach we derive new near-, mid-infrared...
The Gaia second Data Release (DR2) presents a first mapping of full-sky RR Lyrae stars and Cepheids observed by the spacecraft during initial 22 months science operations. Specific Object Study (SOS) pipeline, developed to validate fully characterise (SOS Cep&RRL) Gaia, has been presented in documentation papers accompanying Release. Here we describe how SOS pipeline was modified allow for processing multiband (G, G_BP G_RP) time series photometry all-sky candidate variables produce...
We compare the Gaia DR2 and EDR3 performances in study of Magellanic Clouds show clear improvements precision accuracy new release. also that systematics still present data make determination 3D geometry LMC a difficult endeavour; this is at very limit usefulness astrometry, but it may become feasible with use additional external data. derive radial tangential velocity maps global profiles for several subsamples we defined. To our knowledge, first time two planar components ordered random...
Parallaxes for 331 classical Cepheids, 31 Type II Cepheids and 364 RR Lyrae stars in common between Gaia the Hipparcos Tycho-2 catalogues are published Data Release 1 (DR1) as part of Tycho-Gaia Astrometric Solution (TGAS). In order to test these first parallax measurements primary standard candles cosmological distance ladder, that involve astrometry collected by during initial 14 months science operation, we compared them with literature estimates derived new period-luminosity ($PL$),...
The Gaia Data Release 2 (DR2): we summarise the processing and results of identification variable source candidates RR Lyrae stars, Cepheids, long period variables (LPVs), rotation modulation (BY Dra-type) delta Scuti & SX Phoenicis short-timescale variables. In this release aim to provide useful but not necessarily complete samples candidates. processed data consist G, BP, RP photometry during first 22 months operations as well positions parallaxes. Various methods from classical...
Gaia DR3 publishes a catalogue of full-sky RR Lyrae stars (RRLs) observed during the initial 34 months science operations, that were processed through Specific Object Study (SOS) pipeline for Cepheids and RRLs (SOS Cep&RRL) by Gaia. The SOS Cep&RRL validation candidate relies on tools include Period (P) G-amplitude diagram P-phi21 -phi31 parameters G light curve Fourier decomposition, based sample bona fide known (Gold Sample). processing led to 271779 listed in vari_rrlyrae table DR3. By...
Context. Cepheids are pulsating stars that play a crucial role in several astrophysical contexts. Among the different types, Classical fundamental tools for calibration of extragalactic distance ladder. They also powerful stellar population tracers context Galactic studies. The Gaia Third Data Release (DR3) publishes improved data on collected during initial 34 months operations. Aims. We present DR3 catalogue all obtained through analysis carried out with Specific Object Study (SOS) Cep&RRL...
Gaia Data Release 3 (DR3) provides a wealth of new data products for the astronomical community to exploit, including astrophysical parameters half billion stars. In this work we demonstrate high quality these and illustrate their use in different contexts. We query parameter tables along with other DR3 derive samples stars interest. validate our results by using catalogue itself comparison external data. have produced six homogeneous across HR diagram exploit. first focus on three that span...
Abstract The Vera C. Rubin Legacy Survey of Space and Time (LSST) holds the potential to revolutionize time domain astrophysics, reaching completely unexplored areas Universe mapping variability scales from minutes a decade. To prepare maximize LSST data for exploration transient variable Universe, one four pillars science, Transient Variable Stars Science Collaboration, eight Collaborations, has identified research interest requirements, paths enable them. While our roadmap is...
Context. More than half a million of the 1.69 billion sources in Gaia Data Release 2 (DR2) are published with photometric time series that exhibit light variations during 22 months observation. Aims. An all-sky classification common high-amplitude pulsators (Cepheids, long-period variables, δ Scuti/SX Phoenicis, and RR Lyrae stars) is provided for stars brightness greater 0.1 mag G band. Methods. A semi-supervised approach was employed, firstly training multi-stage random forest classifiers...
Context. In the current ever increasing data volumes of astronomical surveys, automated methods are essential. Objects known classes from literature necessary for training supervised machine learning algorithms, as well verification/validation their results. Aims.The primary goal this work is to provide a comprehensive set variable objects cross-matched with \textit{Gaia}~DR3 sources, including large number both variability types and representatives, in order cover much possible sky regions...
We present results from an analysis of $\sim$ 29,000 RR Lyrae stars located in the Large Magellanic Cloud (LMC). For these objects, near-infrared time-series photometry VISTA survey Clouds system (VMC) and optical data OGLE (Optical Gravitational Lensing Experiment) IV Gaia Data Release 2 catalogue confirmed were exploited. Using VMC magnitudes we derived period-luminosity (PL), period-luminosity-metallicity (PLZ), period-Wesenheit (PW) period-Wesenheit-metallicity (PWZ) relations all...
We present new luminosity-metallicity (LZ; MV-[Fe/H] and MG-[Fe/H]) relations and, for the first time, empirical, Gaia three-band (G,GBP,GRP) period-Wesenheit-metallicity (PWZ) of RR Lyrae stars (RRLs) derived using a hierarchical Bayesian approach accurate parallaxes published these variables in Early Data Release 3 (EDR3). In previous study we obtained hierarchically-derived LZ from sample about four hundred Milky Way field RRLs with G-band light curves trigonometric 2 (DR2), V mean...
We have performed the first study of variable star population Ursa Major I (UMa I), an ultra-faint dwarf satellite recently discovered around Milky Way (MW) by Sloan Digital Sky Survey. Combining time series observations in B and V bands from four different telescopes, we identified seven RR Lyrae stars UMa I, which five are fundamental-mode (RRab) two first-overtone pulsators (RRc). Our V, − color–magnitude diagram reaches ∼ 23 mag (at a signal-to-noise ratio ∼6) shows features typical...
Context. As part of Gaia Data Release 3 (Gaia DR3), epoch photometry has been released for 1.2 million sources centred on M31. This is a taster 4 where all the will be released. Aims. In this paper content Andromeda Photometric Survey described, including statistics to assess quality data. Known issues with are also outlined. Methods. Methods given improve interpretation photometry, in particular, method error renormalization. Also, use correlations between three photometric passbands allows...
We present B, V time-series photometry of Andromeda XIX (And XIX), the most extended (half-light radius 62) Andromeda's dwarf spheroidal companions, which we observed with Large Binocular Cameras at Telescope. surveyed a 23' × area centered on And and deepest color–magnitude diagram (CMD) ever obtained for this galaxy, reaching, ∼ 26.3 mag, about one magnitude below horizontal branch (HB). The CMD shows prominent slightly widened red giant branch, along predominantly HB, extends to blue...
We present B and V time-series photometry of Andromeda XXV, the third galaxy in our program on Andromeda's satellites, that we have imaged with Large Binocular Cameras Telescope. The field XXV is found to contain 63 variable stars, for which light curves characteristics variation (period, amplitudes, variability type, mean magnitudes, etc.). sample includes 58 RR Lyrae variables (46 fundamental-mode $-$ RRab, 12 first-overtone $-$RRc, pulsators), three anomalous Cepheids, one eclipsing...