C. Lazzoni
A5049830424- Stellar, planetary, and galactic studies
- Astronomy and Astrophysical Research
- Astrophysics and Star Formation Studies
- Astro and Planetary Science
- Astronomical Observations and Instrumentation
- Gamma-ray bursts and supernovae
- Adaptive optics and wavefront sensing
- Calibration and Measurement Techniques
- Spectroscopy and Laser Applications
- Molecular Spectroscopy and Structure
- Astrophysical Phenomena and Observations
- Chemical Thermodynamics and Molecular Structure
- Advanced Neural Network Applications
- Nuclear physics research studies
- Scientific Measurement and Uncertainty Evaluation
- Robotics and Sensor-Based Localization
- Pulsars and Gravitational Waves Research
- Astronomical and nuclear sciences
- Solar and Space Plasma Dynamics
- Advanced Optical Sensing Technologies
- Geomagnetism and Paleomagnetism Studies
- Geophysical Methods and Applications
- Earthquake Detection and Analysis
- earthquake and tectonic studies
- Space Exploration and Technology
University of Exeter
2022-2024
Osservatorio Astronomico di Padova
2016-2024
ETH Zurich
2023
University of Padua
2017-2022
Phillips Exeter Academy
2022
Istituto Nazionale di Fisica Nucleare, Galileo Galilei Institute for Theoretical Physics
2018-2021
National Institute for Astrophysics
2019
Young circumstellar disks are of prime interest to understand the physical and chemical conditions under which planet formation takes place. Only very few detections candidates within these exist, most them currently suspected be disk features. In this context, transition around young star PDS 70 is particular interest, due its large gap identified in previous observations, indicative ongoing formation. We aim search for presence planets structures disk-planet interactions other evolutionary...
Aims: We aim to characterize the orbital and atmospheric properties of PDS 70 b, which was first identified on May 2015 in course SHINE survey with SPHERE, extreme adaptive-optics instrument at VLT. Methods: obtained new deep SPHERE/IRDIS imaging SPHERE/IFS spectroscopic observations b. The astrometric baseline now covers 6 years allows us perform an analysis. For time, we present spectrophotometry young planet almost entire near-infrared range (0.96 3.8 micrometer). use different models...
We present the highest fidelity spectrum to date of a planetary-mass object. VHS 1256 b is $<$20 M$_\mathrm{Jup}$ widely separated ($\sim$8\arcsec, = 150 au), young, companion that shares photometric colors and spectroscopic features with directly imaged exoplanets HR 8799 c, d, e. As an L-to-T transition object, exists along region color-magnitude diagram where substellar atmospheres from cloudy clear. observed 1256~b \textit{JWST}'s NIRSpec IFU MIRI MRS modes for coverage 1 $\mu$m 20 at...
We present JWST Early Release Science (ERS) coronagraphic observations of the super-Jupiter exoplanet, HIP 65426 b, with Near-Infrared Camera (NIRCam) from 2-5 $\mu$m, and Mid-Infrared Instrument (MIRI) 11-16 $\mu$m. At a separation $\sim$0.82" (86$^{+116}_{-31}$ au), b is clearly detected in all seven our observational filters, representing first images an exoplanet to be obtained by JWST, ever direct detection beyond 5 These demonstrate that exceeding its nominal predicted performance up...
The substellar companion HD206893b has recently been discovered by direct imaging of its disc-bearing host star with the SPHERE instrument. We investigate atypical properties companion, which reddest near-infrared colours among all known objects, either orbiting a or isolated, and we provide comprehensive characterisation star-disc-companion system. conducted follow-up adaptive optics spectro-imaging SPHERE, multiinstrument star. obtain R=30 spectrum from 0.95 to 1.64 micron additional...
Context. In recent decades, direct imaging has confirmed the existence of substellar companions (exoplanets or brown dwarfs) on wide orbits (>10 au) around their host stars. striving to understand formation and evolution mechanisms, in 2015 we initiated SPHERE infrared survey for exoplanets (SHINE), a systematic young, nearby stars that is targeted at exploring demographics. Aims. We aim detect characterize population giant planets dwarfs beyond snow line Combined with completeness, our...
Context. Large surveys with new-generation high-contrast imaging instruments are needed to derive the frequency and properties of exoplanet populations separations from ~5 300 au. A careful assessment stellar is crucial for a proper understanding when, where, how frequently planets form, they evolve. The sensitivity detection limits age makes this key parameter direct surveys. Aims. We describe SpHere INfrared survey Exoplanets (SHINE), largest planet-search campaign initiated at VLT in 2015...
The direct characterization of exoplanetary systems with high contrast imaging is among the highest priorities for broader exoplanet community. As large space missions will be necessary detecting and characterizing exo-Earth twins, developing techniques technology exoplanets a driving focus For first time, JWST directly observe extrasolar planets at mid-infrared wavelengths beyond 5$\mu$m, deliver detailed spectroscopy revealing much more precise chemical abundances atmospheric conditions,...
Abstract The unprecedented medium-resolution ( R λ ∼ 1500–3500) near- and mid-infrared (1–18 μ m) spectrum provided by JWST for the young (140 ± 20 Myr) low-mass (12–20 M Jup ) L–T transition (L7) companion VHS 1256 b gives access to a catalog of molecular absorptions. In this study, we present comprehensive analysis data set utilizing forward-modeling approach applying our Bayesian framework, ForMoSA . We explore five distinct atmospheric models assess their performance in estimating key...
Context. PDS 70 is a young (5.4 Myr), nearby (~113 pc) star hosting known transition disk with large gap. Recent observations SPHERE and NACO in the near-infrared (NIR) allowed us to detect planetary mass companion, PDS70b, within cavity. Moreover, H_alpha MagAO MUSE revealed emission associated PDS70b another new companion candidate, PDS70c, at larger separation from star. Aims. Our aim confirm discovery of second planet PDS70c using VLT, further characterize its physical properties, search...
Aims. HD 206893 is a nearby debris disk star that hosts previously identified brown dwarf companion with an orbital separation of ∼10 au. Long-term precise radial velocity (RV) monitoring, as well anomalies in the system proper motion, has suggested presence additional, inner system. Methods. Using information from ongoing precision RV measurements HARPS spectrograph, Gaia host astrometry, we have undertaken multi-epoch search for purported additional planet using VLTI/GRAVITY instrument....
The SHINE project is a 500-star survey performed with SPHERE on the VLT for purpose of directly detecting new substellar companions and understanding their formation early evolution. Here we present an initial statistical analysis subsample 150 stars that are representative full sample. Our goal to constrain frequency masses between 1 75 MJup semimajor axes 5 300 au. We adopt detection limits as function angular separation from data all converted into mass projected orbital using...
The assessment of the frequency planetary systems reproducing Solar System's architecture is still an open problem. Detailed study multiplicity and generally hampered by limitations in quality, temporal extension observing strategy, causing difficulties detecting low-mass inner planets presence outer giant bodies. We present results high-cadence high-precision HARPS observations on 20 solar-type stars known to host a single long-period planet order search for additional companions estimate...
HD95086 (A8V, 17Myr) hosts a rare planetary system for which multi-belt debris disk and giant planet of 4-5MJup have been directly imaged. Our study aims to characterize the physical orbital properties HD95086b, search additional planets at short wide orbits image cold outer belt in scattered light. We used HARPS ESO 3.6m telescope monitor radial velocity over 2 years investigate existence less than 3au distance. With IRDIS dual-band imager IFS integral field spectrograph SPHERE VLT, we...
Young planets are expected to cause perturbations in protostellar disks that may be used infer their presence. Clear detection of still-forming embedded within gas-rich is rare. HD 169142 a very young Herbig Ae-Be star surrounded by pre-transitional disk, composed at least three rings. While claims sub-stellar objects around this have been made previously, follow-up studies remain inconclusive. We SPHERE ESO VLT obtain sequence high-contrast images the immediate surroundings over about...
The nearby Herbig Be star HD100546 is known to be a laboratory for the study of protoplanets and their relation with circumstellar disk that carved by at least 2 gaps. We observed environment high contrast imaging exploiting several different observing modes SPHERE, including datasets with/without coronagraphs, dual band imaging, integral field spectroscopy polarimetry. picture emerging from these data sets complex. Flux-conservative algorithms images clearly show up 200au. More aggressive...
Abstract We present a performance analysis for the aperture masking interferometry (AMI) mode on board James Webb Space Telescope Near Infrared Imager and Slitless Spectrograph (JWST/NIRISS). Thanks to self-calibrating observables, AMI accesses inner working angles down even within classical diffraction limit. The scientific potential of this has recently been demonstrated by Early Release Science (ERS) 1386 program with deep search close-in companions in HIP 65426 exoplanetary system. As...
During the past decade, state-of-the-art planet-finder instruments like SPHERE@VLT, coupling coronagraphic devices and extreme adaptive optics systems, unveiled, thanks to large surveys, around 20 planetary mass companions at semi-major axis greater than 10 astronomical units. Direct imaging being only detection technique be able probe this outer region of SPHERE infrared survey for exoplanets (SHINE) was designed conducted from 2015 2021 study demographics such young gas giant planets 400...
Over the past decade, large surveys with state-of-the-art planet-finder instruments such as Spectro-Polarimetric High-contrast Exoplanet REsearch on board Very Large Telescope (SPHERE@VLT), coupled coronagraphic devices and extreme adaptive optics (AO) systems, have unveiled around 20 planetary mass companions at a semi-major axis greater than 10 astronomical units (au). Since direct imaging is only detection technique ability to probe this outer region of SPHERE infrared survey for...
HIP 65426 b is a recently discovered exoplanet imaged during the course of SPHERE-SHINE survey. Here we present new $L'$ and $M'$ observations planet from NACO instrument at VLT NACO-ISPY survey, as well $Y-H$ spectrum $K$-band photometry SPHERE-SHINE. Using these data, confirm nature companion warm, dusty with mid-L spectral type. From comparison its SED BT-Settl atmospheric models, derive best-fit effective temperature $T_{\text{eff}}=1618\pm7$ K, surface gravity $\log...
Context. The 51 Eridani system harbors a complex architecture with its primary star forming hierarchical the binary GJ 3305AB at projected separation of 2000 au, giant planet orbiting 13 and low-mass debris disk around possibly cold component warm inferred from spectral energy distribution. Aims. We aim to better constrain orbital parameters known planet. Methods. monitored over three years 2015 2018 VLT/SPHERE exoplanet imaging instrument. Results. measure an motion for ~130 mas slightly...
Jets are rarely associated with pre-main-sequence intermediate-mass stars. Optical and near-IR observations of jet-driving sources often hindered by the presence a natal envelope. around partly embedded useful diagnostic to constrain geometry concealed protoplanetary disk. In fact, mechanisms affected both spatial anisotropies episodic variations at (sub-)au scale from star. We obtained rich set high-contrast VLT/SPHERE 0.6 micron 2.2 young star RY Tau. Given proximity Sun this source, our...
Context. High contrast imaging enables the determination of orbital parameters for substellar companions (planets, brown dwarfs) from observed relative astrometry and estimation model age-dependent masses their magnitudes or spectra. Combining astrometric positions with radial velocity gives direct constraints on orbit dynamical companions. A dwarf was discovered VLT/SPHERE instrument at Very Large Telescope (VLT) in 2017, which orbits ∼11 au around HD 206893. Its mass estimated between 12...
Debris disks are the intrinsic by-products of star and planet formation processes. Most likely due to instrumental limitations their natural faintness, little is known about debris around low-mass stars, especially when it comes spatially resolved observations. We present new VLT/SPHERE IRDIS Dual-Polarization Imaging (DPI) observations in which we detect dust ring M2 spectral type TWA\,7. Combined with additional Angular Differential aim at a fine characterization disk setting constraints...
In 2015, we initiated a survey of Scorpius-Centaurus A-F stars that are predicted to host warm-inner and cold-outer belts debris similar the case system HR~8799. The aims resolve disks detect planets responsible for disk morphology. this paper, study F-type star HIP~67497 present first-order modelisation in order derive its main properties. We used near-infrared integral field spectrograph (IFS) dual-band imager IRDIS VLT/SPHERE obtain angular-differential imaging observations circumstellar...