papers

Publications (41)

astro-ph.EP2025

Discovery of a multi-planetary system orbiting the aged Sun-like star HD 224018

M. Damasso, L. Naponiello, A. Anna John +22

In 2016, Kepler/K2 detected a system of two sub-Neptunes transiting the star HD 224018, one of them showing a mono-transit event. In 2017, we began a spectroscopic follow-up with H…

astro-ph.EP2025

Transit Timing Variations in HIP 41378: CHEOPS and TESS confirm a non-transiting sixth planet in the system

P. Leonardi, L. Borsato, L. Pagliaro +89

In multiple-planet systems, gravitational interactions of exoplanets could lead to transit timing variations (TTVs), whose amplitude becomes significantly enhanced when planets are…

astro-ph.EP2025

A four-planet system orbiting the old thick disk star TOI-1203

D. Gandolfi, A. Alnajjarine, L. M. Serrano +120

TOI-1203 is a bright (V=8.6) G3 V star known to host a transiting warm sub-Neptune on a 25.5 d orbit. Here we report on an intensive high-precision radial velocity and photometric…

astro-ph.EP2026

The GAPS Programme at TNG. LXXIII. Confirmation of the hot sub-Neptune TOI-4602 b (HD 25295 b), a key target for future atmospheric characterization

C. Di Maio, S. Benatti, D. Locci +25

Precise mass and radius measurements of small, transitional exoplanets, such as super-Earths and sub-Neptunes, are essential to constrain their bulk density and formation history,…

astro-ph.EP2023

The GAPS programme at TNG XLIX. TOI-5398, the youngest compact multi-planet system composed of an inner sub-Neptune and an outer warm Saturn

G. Mantovan, L. Malavolta, S. Desidera +68

Short-period giant planets are frequently found to be solitary compared to other classes of exoplanets. Small inner companions to giant planets with 15 days are known…

astro-ph.EP2024

The GAPS Programme at TNG: LIV. A HeI survey of close-in giant planets hosted by M-K dwarf stars with GIANO-B

G. Guilluy, M. C. D'Arpa, A. S. Bonomo +30

Atmospheric escape plays a fundamental role in shaping the properties of exoplanets. The metastable near-infrared helium triplet at 1083.3 nm (HeI) is a powerful proxy of extended…

astro-ph.EP2026

The GAPS programme at TNG LXXI. A sub-Neptune suitable for atmospheric characterization in a multiplanet and mutually inclined system orbiting the bright K dwarf TOI-5789 (HIP 99452)

A. S. Bonomo, L. Naponiello, A. Sozzetti +37

Sub-Neptunes with planetary radii of are the most common planets around solar-type stars in short-period ( d) orbits. It is still unclear, howe…

astro-ph.EP2024

TOI-837 b: characterisation, formation and evolutionary history of an infant warm Saturn-mass planet

M. Damasso, D. Polychroni, D. Locci +15

We aim to determine the fundamental properties of the 35 Myr old star TOI-837 and its close-in Saturn-sized planet, and to investigate the system's formation and evolutionary…

astro-ph.EP2025

Improved characterization of the TOI-2141 system: a dense sub-Neptune with non-transiting inner and outer companions

R. Luque, K. W. F. Lam, J. Cabrera +87

We aim to refine the fundamental parameters of the TOI-2141 planetary system, which includes a transiting sub-Neptune orbiting a Sun-like star in a relatively long orbit of 18.26 d…

astro-ph.EP2025

Transit-timing variations in the AU Mic system observed with CHEOPS

Á. Boldog, Gy. M. Szabó, L. Kriskovics +86

AU Mic is a very active M dwarf with an edge-on debris disk and two transiting sub-Neptunes with a possible third planetary companion. The two transiting planets exhibit significan…

astro-ph.EP2025

The Hot-Neptune Initiative (HONEI) I. Two hot sub-Neptunes on a close-in, eccentric orbit (TOI-5800 b) and a farther-out, circular orbit (TOI-5817 b)

L. Naponiello, S. Vissapragada, A. S. Bonomo +37

Neptune-sized exoplanets are key targets for atmospheric studies, yet their formation and evolution remain poorly understood due to their diverse characteristics and limited sample…

astro-ph.EP2026

The GAPS programme at TNG: LXXVI. TOI-1533: a compact system hosting a super-Neptune-mass pair with disparate radii

G. Mantovan, V. Nascimbeni, S. Desidera +49

The present-day architecture of planetary systems contains information about their formation and migration histories. The origin of hot Jupiters (HJs, P 10 d, $R_{\rm p}…

astro-ph.EP2024

The GAPS Programme at TNG. LIII. New insights on the peculiar XO-2 system

A. Ruggieri, S. Desidera, K. Biazzo +20

Planets in binary systems are a fascinating and yet poorly understood phenomenon. Since there are only a few known large-separation systems in which both components host planets, c…

astro-ph.EP2026

TOI-159 b: an eccentric hot-Jupiter planet around a young, pulsating Doradus star

G. Mantovan, A. Llancaqueo Albornoz, A. Psaridi +16

Fast-rotating hot stars are challenging targets for exoplanet searches due to rotational broadening and stellar variability. Moreover, hot stars often exhibit pulsations, an additi…

astro-ph.EP2024

The GAPS programme at TNG. LVII. TOI-5076b: A warm sub-Neptune planet orbiting a thin-to-thick-disk transition star in a wide binary system

M. Montalto, N. Greco, K. Biazzo +36

Aims. We report the confirmation of a new transiting exoplanet orbiting the star TOI-5076. Methods. We present our vetting procedure and follow-up observations which led to the con…

astro-ph.EP2026

The 35-Myr old infant planet TOI-837 b has a mildly misaligned orbit

G. Mantovan, L. Malavolta, F. Marzari +6

The measurement of the spin-orbit obliquity, that is, the angle between the orbital axis of a planet and the stellar spin axis, provides crucial insights into how planets form and…

astro-ph.EP2026

The GAPS Programme at the TNG: LXX. TOI-5734b: A hot sub-Neptune orbiting a relatively young K dwarf with an Earth-like density

S. Filomeno, T. Trifonov, M. Damasso +40

Increasing interest in young exoplanets is leading to a growing effort to understand the formation and evolutionary processes responsible for their different architectures. One int…

astro-ph.EP2024

Orbital obliquity of the young planet TOI-5398 b and the evolutionary history of the system

G. Mantovan, L. Malavolta, D. Locci +19

Multi-planet systems exhibit remarkable architectural diversity. However, short-period giant planets are typically isolated. Compact systems like TOI-5398, with an outer close-orbi…

astro-ph.EP2024

The GAPS Programme at TNG. LXV. Precise density measurement of TOI-1430 b, a young planet with an evaporating atmosphere

D. Nardiello, J. M. Akana Murphy, R. Spinelli +34

Small-sized exoplanets in tight orbits around young stars (10-1000 Myr) give us the opportunity to investigate the mechanisms that led to their formation, the evolution of their ph…

astro-ph.SR2023

New members of the Lupus I cloud based on Gaia astrometry Physical and accretion properties from X-Shooter spectra

F. Z. Majidi, J. M. Alcala', A. Frasca +13

We characterize twelve young stellar objects (YSOs) located in the Lupus I region, spatially overlapping with the Upper Centaurus Lupus (UCL) sub-stellar association. The aim of th…

astro-ph.EP2026

The GAPS Programme with HARPS-N at TNG LXXVII. Occurrence rates of small close-in planets in the presence of cold Jupiters

A. Ruggieri, S. Desidera, M. Pinamonti +18

The paper compiles a homogeneous sample of 137 stars with cold Jupiters and uses radial‑velocity data, including new HARPS‑N observations, to measure how often inner small planets…

#cold jupiters#inner small planets#radial velocity#occurrence rates
astro-ph.EP2026

: Accelerating Bayesian atmospheric retrievals with transformer neural networks

L. Pagliaro, T. Zingales, G. Piotto +2

Computationally expensive and time-consuming Bayesian atmospheric retrievals pose a significant bottleneck for the rapid analysis of high-quality exoplanetary spectra from present…

astro-ph.EP2024

Architecture of TOI-561 planetary system

G. Piotto, T. Zingales, L. Borsato +89

We present new observations from CHEOPS and TESS to clarify the architecture of the planetary system hosted by the old Galactic thick disk star TOI-561. Our global analysis, which…

astro-ph.EP2026

Discovery and characterisation of two exoplanets orbiting the metal-poor, solar-type star TOI-5788 with TESS, CHEOPS, and HARPS-N

Ben S. Lakeland, A. Mortier, R. D. Haywood +48

We present the discovery and characterisation of two transiting exoplanets orbiting the metal-poor, solar-type star TOI-5788. From our analysis of six \textit{TESS} sectors and a d…

astro-ph.EP2025

The Hot Neptune Initiative (HONEI) II. TOI-5795 b: A hot super-Neptune orbiting a metal-poor star

F. Manni, L. Naponiello, L. Mancini +31

The formation of Neptune planets with orbital periods less than 10\,days remains uncertain. They might have developed similarly to longer-period counterparts, emerged from rare col…

astro-ph.SR2024

The GAPS Programme at TNG. LXI. Atmospheric parameters and elemental abundances of TESS young exoplanet host stars

S. Filomeno, K. Biazzo, M. Baratella +26

The study of exoplanets at different evolutionary stages can shed light on their formation, migration, and evolution. The determination of exoplanet properties depends on the prope…

astro-ph.EP2021

A PSF-based Approach to TESS High quality data Of Stellar clusters (PATHOS) -- IV. Candidate exoplanets around stars in open clusters: frequency and age-planetary radius distribution

D. Nardiello, M. Deleuil, G. Mantovan +7

The knowledge of the ages of stars hosting exoplanets allows us to obtain an overview on the evolution of exoplanets and understand the mechanisms affecting their life. The measure…

astro-ph.EP2026

A tidally detached super Neptune on a strongly misaligned retrograde orbit

G. Mantovan, L. Malavolta, A. F. Lanza +18

The obliquity between a planet's orbital axis and its host star's spin axis provides crucial insights into planetary formation and migration. Planets with scaled semi-major axes ($…

astro-ph.EP2023

The GAPS Programme at TNG L -- TOI-4515 b: An eccentric warm Jupiter orbiting a 1.2 Gyr-old G-star

I. Carleo, L. Malavolta, S. Desidera +68

Context. Different theories have been developed to explain the origins and properties of close-in giant planets, but none of them alone can explain all of the properties of the war…

astro-ph.EP2021

TIC~257060897b: an inflated, low-density, hot-Jupiter transiting a rapidly evolving subgiant star

M. Montalto, L. Malavolta, J. Gregorio +7

We report the discovery of a new transiting exoplanet orbiting the star TIC~257060897 and detected using {\it TESS} full frame images. We acquired HARPS-N time-series spectroscopic…

astro-ph.EP2024

The K2-24 planetary system revisited by CHEOPS

V. Nascimbeni, L. Borsato, P. Leonardi +82

K2-24 is a planetary system composed of two transiting low-density Neptunians locked in an almost perfect 2:1 resonance and showing large TTVs, i.e., an excellent laboratory to sea…

astro-ph.EP2026

The GAPS programme at TNG LXX. HD 128717 B/Gaia-6 B: a long-period eccentric low-mass brown dwarf from astrometry and radial velocities

M. Pinamonti, A. Sozzetti, D. Barbato +24

The transition regime between giant planets (GPs) and brown dwarfs (BDs) is still an open subject of study in exoplanetary science. A complete understanding of the population of lo…

astro-ph.EP2024

The GAPS programme at TNG LXIV: An inner eccentric sub-Neptune and an outer sub-Neptune-mass candidate around BD+00 444 (TOI-2443)

L. Naponiello, A. S. Bonomo, L. Mancini +25

We examined in depth the star BD+00 444 (GJ 105.5, TOI-2443; V = 9.5 mag; d = 23.9 pc), with the aim of characterizing and confirming the planetary nature of its small companion, t…

astro-ph.SR2025

A Decade of Solar High-Fidelity Spectroscopy and Precise Radial Velocities from HARPS-N

X. Dumusque, K. Al Moulla, M. Cretignier +53

We recently released 10 years of HARPS-N solar telescope and the goal of this manuscript is to present the different optimisations made to the data reduction, to describe data cura…

astro-ph.EP2024

The GAPS programme at TNG -- LXIII. Photo-evaporating puzzle: Exploring the enigmatic nature of TOI-5398 b atmospheric signal

M. C. D'Arpa, G. Guilluy, G. Mantovan +26

Atmospheric characterization is key to understanding exoplanetary systems, offering insights into the planets current and past conditions. By analyzing key lines like H alpha and t…

astro-ph.EP2026

The GAPS programme at TNG LXXV. Validating and confirming Gaia substellar astrometric candidates with HARPS-N

D. Barbato, M. Pinamonti, A. Sozzetti +22

The astrometric measurements provided by the Gaia space mission represent a key advancement in the search and characterization of exoplanets, helping in particular to solve the mas…

astro-ph.EP2024

The inflated, eccentric warm Jupiter TOI-4914 b orbiting a metal-poor star, and the hot Jupiters TOI-2714 b and TOI-2981 b

G. Mantovan, T. G. Wilson, L. Borsato +32

Recent observations of giant planets have revealed unexpected bulk densities. Hot Jupiters, in particular, appear larger than expected for their masses compared to planetary evolut…

astro-ph.EP2024

The GAPS programme at TNG LX Atmospheric characterisation of KELT-9 b via single-line analysis: Detection of six H I Balmer lines, Na I, Ca I, Ca II, Fe I, Fe II, Mg I, Ti II, Sc II, and Cr II

M. C. D'Arpa, A. Saba, F. Borsa +27

We analysed six primary transits of the ultra-hot Jupiter KELT-9,b obtained with the HARPS-N high-resolution spectrograph in the context of the Global Architecture of Planetary Sys…

astro-ph.EP2024

A joint effort to discover and characterize two resonant mini Neptunes around TOI-1803 with TESS, HARPS-N and CHEOPS

T. Zingales, L. Malavolta, L. Borsato +130

We present the discovery of two mini Neptunes near a 2:1 orbital resonance configuration orbiting the K0 star TOI-1803. We describe their orbital architecture in detail and suggest…

astro-ph.EP2024

The GAPS Programme at TNG. LIX. A characterisation study of the 300 Myr old multi-planetary system orbiting the star BD+40 2790 (TOI-2076)

M. Damasso, D. Locci, S. Benatti +35

We collected more than 300 high-resolution spectra of the 300 Myr old star BD+40 2790 (TOI-2076) over ~3 years. This star hosts three transiting planets discovered by TESS, with or…

astro-ph.SR2023

The GAPS programme at TNG XLIII. A massive brown dwarf orbiting the active M dwarf TOI-5375

J. Maldonado, A. Petralia, G. Mantovan +23

Context. Massive substellar companions orbiting active low-mass stars are rare. They, however, offer an excellent opportunity to study the main mechanisms involved in the formation…