M. Pinamonti
A5013607333- Stellar, planetary, and galactic studies
- Astronomy and Astrophysical Research
- Astro and Planetary Science
- Astrophysics and Star Formation Studies
- Gamma-ray bursts and supernovae
- Astronomical Observations and Instrumentation
- Calibration and Measurement Techniques
- Space Exploration and Technology
- Astrophysical Phenomena and Observations
- Solar and Space Plasma Dynamics
- Scientific Research and Discoveries
- Geomagnetism and Paleomagnetism Studies
- Atmospheric Ozone and Climate
- Spectroscopy and Laser Applications
- Planetary Science and Exploration
- High-pressure geophysics and materials
- Spectroscopy and Chemometric Analyses
- Pulsars and Gravitational Waves Research
- Spacecraft and Cryogenic Technologies
- Statistical and numerical algorithms
- Relativity and Gravitational Theory
- Advanced Frequency and Time Standards
- Earth Systems and Cosmic Evolution
- Scientific Measurement and Uncertainty Evaluation
- Nuclear physics research studies
Osservatorio Astrofisico di Torino
2017-2024
National Institute for Astrophysics
2020-2023
Trieste Astronomical Observatory
2016-2017
University of Trieste
2016-2017
Istituto Nazionale di Fisica Nucleare, Sezione di Genova
2017
The exoplanet population characterized by relatively short orbital periods ( P < 100 d) around solar-type stars is dominated super-Earths and sub-Neptunes. However, these planets are missing in our Solar System the reason behind this absence still unknown. Two theoretical scenarios invoke role of Jupiter as possible culprit: may have acted a dynamical barrier to inward migration sub-Neptunes from beyond water iceline; alternatively, considerably reduced flux material (pebbles) required...
Radial-velocity (RV) signals induce RV variations an order of magnitude larger than the signal created by orbit Earth-twins, thus preventing their detection. The goal this paper is to compare efficiency different methods used deal with stellar recover extremely low-mass planets despite. However, because observed at m/s precision level or below a combination induced unresolved orbiting planets, star, and instrument, performing such comparison using real data challenging. To circumvent...
We present the confirmation of two new planets transiting nearby mid-M dwarf LTT 3780 (TIC 36724087, TOI-732, $V=13.07$, $K_s=8.204$, $R_s$=0.374 R$_{\odot}$, $M_s$=0.401 M$_{\odot}$, d=22 pc). The planet candidates are identified in a single TESS sector and validated with reconnaissance spectroscopy, ground-based photometric follow-up, high-resolution imaging. With measured orbital periods $P_b=0.77$ days, $P_c=12.25$ days sizes $r_{p,b}=1.33\pm 0.07$ R$_{\oplus}$, $r_{p,c}=2.30\pm 0.16$...
Most of our current knowledge on planet formation is still based the analysis main-sequence, solar-type stars. Conversely, detailed chemical studies large samples M-dwarf hosts are missing. We develop for first time a methodology to determine stellar abundances elements others than iron M dwarf stars from high-resolution, optical spectra. Our use principal component and sparse Bayesian's methods. made set dwarfs orbiting around an FGK primary with known train applied methods derive...
Context. The existence of hot Jupiters is still not well understood. Two main channels are thought to be responsible for their current location: a smooth planet migration through the protoplanetary disk or circularization an initial highly eccentric orbit by tidal dissipation leading strong decrease in semimajor axis. Different formation scenarios result different observable effects, such as orbital parameters (obliquity and eccentricity) frequency planets at stellar ages. Aims. In context...
We present the complete Bayesian statistical analysis of HArps-n red Dwarf Exoplanet Survey (HADES), which monitored radial velocities a large sample M dwarfs with HARPS-N at TNG, over last 6 years. The targets were selected in narrow range spectral types from M0 to M3, $0.3$ M$_\odot < M_\star 0.71$ M$_\odot$, order study planetary population around well-defined class host stars. take advantage statistics derive an accurate estimate detectability function survey. Our also includes...
Great strides have been made in recent years the understanding of mechanisms involved formation and evolution planetary systems; despite this, many observational facts still do not an explanation. A great contribution to study processes comes from young, low-mass planets, with short orbital periods. In last years, TESS satellite has identified planets this kind, their characterization is mandatory understand how they formed evolved. Within framework GAPS project, we performed validation...
Abstract Exoplanet detection with precise radial velocity (RV) observations is currently limited by spurious RV signals introduced stellar activity. We show that machine-learning techniques such as linear regression and neural networks can effectively remove the activity (due to starspots/faculae) from observations. Previous efforts focused on carefully filtering out in time using modeling like Gaussian process regression. Instead, we systematically only changes average shape of spectral...
We aim to investigate the presence of signatures magnetic cycles and rotation on a sample 71 early M-dwarfs from HADES RV programme using high-resolution time-series spectroscopy Ca II H & K Halpha chromospheric activity indicators, radial velocity series, parameters cross correlation function V-band photometry. used mainly HARPS-N spectra, acquired over four years, add HARPS spectra public ESO database ASAS photometry light-curves as support data, extending baseline observations some stars...
ABSTRACT Based on HARPS-N radial velocities (RVs) and TESS photometry, we present a full characterization of the planetary system orbiting late G dwarf TOI-561. After identification three transiting candidates by TESS, discovered two additional external planets from RV analysis. RVs cannot confirm outer candidate, which would also make dynamically unstable. We demonstrate that transits initially associated with this candidate are instead due to single using RVs. The four TOI-561 include an...
For more than two years, we monitored with the HARPS-N spectrograph 400 Myr-old star HD\,63433, which hosts close-in (orbital periods $P_b\sim7.1$ and $P_c\sim20.5$ days) sub-Neptunes detected by TESS space telescope, it was announced in 2020. Using radial velocities additional photometry, aim to provide first measurement of their masses, improve measure size orbital parameters, study evolution atmospheric mass-loss rate due photoevaporation. We tested state-of-the-art analysis techniques...
Minimising the impact of stellar variability in Radial Velocity (RV) measurements is a critical challenge achieving 10 cm s$^{-1}$ precision needed to hunt for Earth twins. Since 2012, dedicated programme has been underway with HARPS-N, conduct blind RV Rocky Planets Search (RPS) around bright stars Northern Hemisphere. Here we describe results comprehensive search planetary systems two RPS targets, HD 166620 and 144579. Using wavelength-domain line-profile decorrelation vectors mitigate...
The low masses of M dwarfs create attractive opportunities for exoplanet radial-velocity (RV) detections. These stars, however, exhibit strong stellar activity that may attenuate or mimic planetary signals. We present a velocimetric analysis one such dwarf, GJ 3998 (d= parsec ), with two published short-period super-Earths: b and c. use additional data from the HARPS-N spectrograph to confirm these planets look more. carry out joint modelling of: (i) RV signals, (ii) rotation in indicators...
Expanding the number of hot giant planets with atmospheric characterisation can improve our understanding their atmospheres as well formation and evolution mechanisms. In this work, we use high-resolution spectroscopy in near-infrared (NIR) to search for chemical signatures two Jupiters KELT-8 b KELT-23 Ab, perform a first properties. We measured transmission spectrum each target NIR spectrograph GIANO-B at TNG searched signals by cross-correlating data synthetic spectra. order characterise...
Hot Jupiters are among the most suitable targets for atmospheric studies. Expanding number of hot gaseous giant planets with characterisations can improve our understanding chemical-physical properties their atmospheres, as well formation and evolution these extreme planets. In this work, we use high-resolution spectroscopy in near-infrared (NIR) to search chemical signatures atmosphere two KELT-8,b eq K) KELT-23,Ab =1,561±20,K) present a first characterisation properties. We measured...
The TESS mission is searching for transiting planets over the entire sky, including two continuous viewing zones. Data from zones span a long time baseline and offer ideal conditions precise planet radius estimations, enabling community to prepare PLATO mission. We report on validation characterisation of around TOI-1453, K-dwarf star in northern zone. In addition data, we used ground-based photometric, spectroscopic, high-resolution imaging follow-up observations validate planets. obtained...
We present 20 yr of radial velocity (RV) measurements the M1 dwarf Gl15A, combining five years intensive RV monitoring with HARPS-N spectrograph 15 archival HIRES/Keck data. have carried out an MCMC-based analysis time series, inclusive Gaussian Process (GP) approach to description stellar activity induced variations. Our confirms Keplerian nature and refines orbital solution for 11.44-day period super Earth, Gl15A b, reducing its amplitude 1.68 −0.18 +0.17 m s −1 ( M sin i = 3.03 −0.44...
This paper reports on the detailed characterisation of K2-111 planetary system with K2, WASP, and ASAS-SN photometry as well high-resolution spectroscopic data from HARPS-N ESPRESSO. The host, K2-111, is confirmed to be a mildly evolved ($\log g=4.17$), iron-poor ([Fe/H]$=-0.46$), but alpha-enhanced ([$α$/Fe]$=0.27$), chromospherically quiet, very old thick disc G2 star. A global fit, performed by using PyORBIT shows that transiting planet, K2-111b, orbits period $P_b=5.3518\pm0.0004$ d, has...
Context. Small planets around low-mass stars often show orbital periods in a range that corresponds to the temperate zones of their host which are therefore prime interest for planet searches. Surface phenomena such as spots and faculae create periodic signals radial velocities observational activity tracers same range, so they can mimic or hide true planetary signals. Aims. We aim detect Doppler corresponding companions, determine most probable configurations, understand stellar its impact...
Context. Young stars and multi-planet systems are two types of primary objects that allow us to study, understand, constrain planetary formation evolution theories. Aims. We validate the physical nature Neptune-sized planets transiting TOI-942 (TYC 5909-319-1), a previously unacknowledged young star (50 −20 +30 Myr) observed by TESS space mission in Sector 5. Methods. Thanks comprehensive stellar characterization, light curve modeling precise radial-velocity measurements, we validated...
Context. Detecting and characterising exoworlds around very young stars (age ≤10 Myr) are key aspects of exoplanet demographic studies, especially for understanding the mechanisms timescales planet formation migration. Any reliable theory such physical phenomena requires a robust observational database to be tested. However, detection using radial velocity method alone can challenging because amplitude signals caused by magnetic activity orders magnitude larger than those induced even...
Aims. We aim to extract the transmission spectrum of H I Balmer lines ultra-hot Jupiter (UHJ) KELT-20b/MASCARA-2b from observations and further compare results with what was obtained through forward modelling, accounting for non-local thermodynamic equilibrium (NLTE) effects. Methods. extracted line profiles six transits HARPS-N high-resolution spectrograph attached Telescopio Nazionale Galileo telescope. computed temperature-pressure (TP) profile employing HELIOS code in lower atmosphere C...