Context . Binary interactions during the asymptotic giant branch phase can lead to the formation of chemically peculiar stars such as Ba-, CH-, and CEMP-s stars with overabundances of s -process elements as well as carbon. Only a few hundred of these stars have been subject to detailed chemical and/or dynamical studies, typically in non-homogeneous samples. Aims . We compile a systematic sample of s -process-polluted candidates using the fourth data release of the large spectroscopic survey GALAH. We also compare the chemical and orbital properties of these candidates with those of confirmed s -process-polluted stars to gain stronger evidence of their nature. Methods . GALAH DR4 uses neural networks and automatic spectral analysis methods as well as data of a lower spectral resolution than is normally used to characterise these objects. We therefore built a validation sample of s-rich stars before querying the survey, for which we obtained VLT/UVES and Mercator/HERMES high-resolution (>80 000) spectra and analysed them with traditional methods. We compared our stellar parameters and individual abundances with those of the survey and used this validation to define the thresholds that a star in GALAH DR4 must pass to be flagged as a good s -process-rich candidate. Based on our comparisons with the high-resolution complementary spectra, we defined thresholds on five quantities: [s/Fe] > 0.40 dex, [Y/Fe] > 0.22 dex, [Zr/Fe] > 0.26 dex, [Ba/Fe] > 0.19 dex, and [La/Fe] > 0.26 dex. Results . We identified 1059 stars in GALAH DR4 that are good candidates to be s -process-polluted stars, covering a broad parameter space (4000 K < T eff < 6000 K, 0.5 dex < log g < 5.0 dex, −2.0 dex < [Fe/H] < 0.5 dex). They share many similarities with the samples of confirmed s-rich stars, especially their ratios of heavy over light s-elements, which strengthens our confidence in the purity of the sample. When we cross-matched the sample with the literature, we found that only 7% of the candidates have measured orbital periods and eccentricities. This limits a full comparison with confirmed Ba and related star samples for now. However, their binary fraction is, as expected, higher than the one we found for the full GALAH DR4 catalogue. Conclusions . Our sample of candidates is almost five times larger than the number of currently confirmed polluted stars. This and the fact that it has been homogeneously treated by the GALAH survey opens very interesting avenues to compare nucleosynthesis models as well as binary evolution models.

Aims. We investigate how the presence of a binary companion appears to affect dust and molecule formation in the circumstellar environment of a star on the asymptotic giant branch (AGB). Methods.L- and N-band observations obtained over the course of one month with the multi aperTure mid-infrared spectroScopic experiment instrument (MATISSE) at the very large telescope interferometer (VLTI) were used to constrain the distribution of dust and molecules in the close environment of π1 Gru through image reconstruction. The reconstructed images were fit to the interferometric observables, that is, the visibilities and closure phases, using the two Python-based tools Python for MiRA (PYRA) and mean astrophysical images with PYRA (MYTHRA) built around the multi-aperture image reconstruction algorithm (MiRA). Results. Our observations support (i) a wind Roche-lobe overflow (WRLOF) scenario, where mass transfer from the AGB star to its companion produces a possible circumcompanion disk in the L band around π1 Gru C, with a central cavity that likely traces dust sublimation and a circumcompanion envelope in the N band. (ii) A main-sequence nature for the companion: Because both Atacama large millimeter/submillimeter array (ALMA) and the VLTI/MATISSE N-band observations show emission, we favor a thermal infrared emission from the main-sequence star over free-free emission from a with dwarf companion. Finally, (iii) a plume-like structure extending from π1 Gru C, likely marking the onset of the spiral observed at larger scales. Together, this provides direct evidence that links small-scale mass transfer and disk formation through WRLOF to the global circumstellar morphology. Conclusions. These results highlight the atmospheric deformation induced by the companion, reveal ongoing mass transfer between the evolved star and its companion, and indicate a circumcompanion disk-like structure.

Benchmarking fundamental stellar properties is essential for calibrating evolutionary models and establishing empirical relationships between mass, radius, luminosity and related stellar properties. We determine the current ages and initial equatorial velocities at the Zero-Age Main Sequence (ZAMS) for a well-characterized sample of 108 detached main-sequence eclipsing binaries. Evolutionary tracks from the ZAMS to the present are calculated by accounting for tidal interactions, including meridional circulation, and angular momentum loss via stellar winds, under the assumption of circular orbits. System ages are derived by identifying the evolutionary stage at which the calculated radii of both stellar components best match the observed values. While initial velocities for currently synchronized systems cannot be uniquely constrained, as a wide range of initial states naturally converges to synchronisation over time, we are able to determine unique solutions for ZAMS spin velocities in systems that remain asynchronous today. Our models successfully reproduce observed present-day equatorial velocities with a precision of 1%. Two systems, HD 71636 and V396 Cas, were found to have primaries with initially retrograde spin at ZAMS. We also find an increasing dispersion of spin velocities with age. Our results demonstrate that tidal and evolutionary effects in binary systems actively counteract rotational deceleration from stellar winds, effectively preventing the substantial spin-down that typically characterizes the evolution of isolated single stars.

Binary interactions during the AGB phase can lead to the formation of chemically peculiar stars with overabundances of s-process elements. Only a few hundreds of these stars have been subject to detailed chemical or dynamical studies. This work aims at compiling a systematic sample of s-process-polluted candidates using GALAH DR4. We also want to compare their properties with those of confirmed s-polluted stars to have stronger evidence of their nature. GALAH DR4 uses neural networks and automatic spectral analysis methods as well as data of a lower spectral resolution than normally used to characterise these objects. Because of this, we built a validation sample, for which we obtained UVES@VLT and HERMES@Mercator high-resolution spectra. We compare our stellar parameters and abundances with those of the survey and use this validation to define the thresholds that a star in GALAH DR4 must pass to be flagged as a good s-process-rich candidate. Based on our comparisons, we define thresholds on [s/Fe], [Y/Fe], [Zr/Fe], [Ba/Fe], and [La/Fe]. We identified 1059 stars in GALAH DR4 that are good candidates to be s-process polluted stars, covering a broad parameter space. They share many similarities with the samples of confirmed s-rich stars, especially their ratios of heavy over light s-elements ([hs/ls]), which strengthen our confidence in the purity of the sample. We find that only 7

Benchmarking fundamental stellar properties is essential for calibrating evolutionary models and establishing empirical relationships between mass, radius, luminosity, and related stellar properties. We determined the current ages and initial equatorial velocities at the zero age main sequence (ZAMS) for a well-characterized sample of 108 detached main-sequence eclipsing binaries. Evolutionary tracks from the ZAMS to the present day were calculated by accounting for tidal interactions, including meridional circulation, and angular momentum loss via stellar winds, under the assumption of circular orbits. System ages were derived by identifying the evolutionary stage at which the calculated radii of both stellar components best match the observed values. While initial velocities for currently synchronized systems cannot be uniquely constrained, as a wide range of initial states naturally converges to synchronization over time, we were able to determine unique solutions for ZAMS spin velocities in systems that remain asynchronous today. Our models successfully reproduce observed present-day equatorial velocities with a precision of 1%. Two systems, HD 71636 and V396 Cas, were found to have primaries initially with retrograde spin at ZAMS. We also find an increasing dispersion of spin velocities with age. Our results demonstrate that tidal and evolutionary effects in binary systems actively counteract rotational deceleration from stellar winds, effectively preventing the substantial spin-down that typically characterizes the evolution of isolated single stars.

The carbon-enhanced metal-poor stars with hybrid enrichments of slow- and rapid neutron-capture elements, the so-called CEMP-rs stars, still raise many questions due to their elusive abundance signatures. In our recent analysis, we found that heavy r process elements are enhanced in these objects and can be explained by the intermediate neutron-capture process (i-process) occurring in low-mass, very low-metallicity asymptotic giant branch (AGB) stars. However, the origin of actinides such as thorium and uranium is typically associated with explosive nucleosynthesis in highly neutron-rich environments, and their detection in stellar spectra remains challenging due to severe line blending from other elements and carbon-bearing molecules. In this work, we investigate the presence of thorium and uranium abundances in a sample of CEMP-rs stars using their high-resolution spectra obtained with the UVES spectrograph mounted on the UT2 (Kueyen) ESO VLT. Thorium is robustly detected in three stars, while uranium remains marginally detected, allowing only upper limits to be derived. Comparison with theoretical i-process nucleosynthesis models demonstrates that the observed abundances can be reproduced within uncertainties, supporting an i-process origin for these elements. This study reports the first detection of actinides in stars confirmed as CEMP-rs stars, providing new constraints on their nucleosynthetic history. Furthermore, these detections provide a potential way to estimate in the future the time elapsed since the proton-ingestion episode in AGB stars using cosmochronometry techniques, and more generally to place lower limits on the ages of the resulting white dwarf remnants.

Oxygen and carbon-rich AGB stars – and objects directly polluted by them – are excellent laboratories to investigate the nucleosynthesis and mixing processes occurring during the later phases of low- and intermediate-mass star evolution. The determination of the abundances of several s-elements is a key tool for constraining theoretical AGB models. This contribution discusses the main results, recent advances, and current problems on this subject.

Aims. We investigate how the presence of a binary companion appears to affect dust and molecule formation in the circumstellar environment of a star on the asymptotic giant branch (AGB). Methods.L- and N-band observations obtained over the course of one month with the multi aperTure mid-infrared spectroScopic experiment instrument (MATISSE) at the very large telescope interferometer (VLTI) were used to constrain the distribution of dust and molecules in the close environment of π1 Gru through image reconstruction. The reconstructed images were fit to the interferometric observables, that is, the visibilities and closure phases, using the two Python-based tools Python for MiRA (PYRA) and mean astrophysical images with PYRA (MYTHRA) built around the multi-aperture image reconstruction algorithm (MiRA). Results. Our observations support (i) a wind Roche-lobe overflow (WRLOF) scenario, where mass transfer from the AGB star to its companion produces a possible circumcompanion disk in the L band around π1 Gru C, with a central cavity that likely traces dust sublimation and a circumcompanion envelope in the N band. (ii) A main-sequence nature for the companion: Because both Atacama large millimeter/submillimeter array (ALMA) and the VLTI/MATISSE N-band observations show emission, we favor a thermal infrared emission from the main-sequence star over free-free emission from a with dwarf companion. Finally, (iii) a plume-like structure extending from π1 Gru C, likely marking the onset of the spiral observed at larger scales. Together, this provides direct evidence that links small-scale mass transfer and disk formation through WRLOF to the global circumstellar morphology. Conclusions. These results highlight the atmospheric deformation induced by the companion, reveal ongoing mass transfer between the evolved star and its companion, and indicate a circumcompanion disk-like structure.

The Ninth Catalogue of Spectroscopic Binary Orbits ( S-B(9)) is a comprehensive compilation of spectroscopic binaries (SBs) with orbital parameters sourced from the literature, comprising approximately 4000 systems with about 2800 singlelined and 1200 double-lined binaries. This work presents the latest status of the S-B(9) catalogue after over two decades of development since its online inception in 2004. In particular, we expose the statistical properties of SBs in terms of orbital period distributions and eccentricity-period diagrams perspectral type and evolutionary stage. We perform a careful crossmatch with the Gaia Data Release 3 (DR3) to update astrometric parameters and compare with the Gaia DR3 non-single star (NSS) catalogue. Our cross-matching approach uses positional separations, magnitudes, and proper-motion backpropagation to identify counterparts. The final S-B(9) version updated by D. Pourbaix (2021-03-02) includes 4003 SB systems, some in higher order multiples: 152 in triples, 71 in quadruples, and 14 in higher order systems. Among these 4003 SB, 3976 have matching Gaia DR3 identifiers, while 21 are too bright and six too faint for Gaia detection. 10 red S(B)(9)systems with periods larger than 1180 d (including a spectroscopic triple) have been spatially resolved by Gaia DR3. We identify a common sample of 827 S-B(9) binaries cross-matched with Gaia NSS, among which 655 are considered as reliable, based on relative period and absolute eccentricity differences not exceeding 10 per cent. The limited overlap (21 per cent of S-B(9)) is primarily due to selection cuts in NSS SB1 analysis, brightness limits, temporal baselines, and partial orbital solutions in the Gaia NSS catalogue. This study highlights the strengths and limitations of both catalogues and establishes a clean benchmark sample for future binary star research. Our work marks the transition of S-B(9) into S-B(X) , The eXtended Catalogue of Spectroscopic Binary Orbits, featuring a modern relational data base, improved web interface, and Virtual Observatory access standards, aiming to enhance accessibility, data quality, and analysis capabilities for the binary and multiple star community.

Carbon-enhanced metal-poor (CEMP) stars are ancient stars enriched in carbon and heavy elements. Some of these stars exhibit enhanced s -process and/or r -process elements, and hence are classified as CEMP-s, CEMP-rs, or CEMP-r. This classification is challenging due to the limited availability of heavy element abundances, particularly among r -process elements. Heavy r -process elements such as terbium, holmium, thulium, ytterbium, lutetium, tantalum, and iridium have rarely been measured because their sensitive lines are located in the ultraviolet. However, they provide sensitive diagnostics of the s -, r -, and i - nucleosynthetic processes. In this work, we aim to obtain a secure classification of CEMP-s and -rs stars and investigate whether the i -process can account for the measured abundance patterns in CEMP-rs stars. We derive the abundance profiles, notably for 12 heavy r-elements, including, in some cases, tantalum, using high-resolution UVES spectra of 17 CEMP-s and -rs stars. Based on indicators such as the [s/r] abundance ratio or the model-independent “abundance distance”, nine stars are confirmed as CEMP-rs and six as CEMP-s. The classification of two objects remains uncertain. The i -process satisfactorily reproduces the abundance patterns of CEMP-rs stars. However, larger samples are needed to confirm trends with metallicity and clarify how CEMP-rs stars differ from CEMP-s stars.

Context. The Gaia-ESO survey (GES) is a large public spectroscopic survey that acquired spectra for more than 100 000 stars across all major components of the Milky Way. In addition to atmospheric parameters and stellar abundances that have been derived in previous papers of this series, the GES spectra allow us to detect spectroscopic binaries with one (SB1), two (SB2), or more (SBn >= 3) components. Aims. The present paper discusses the statistics of GES SBn >= 2 after analysing 160 727 GIRAFFE HR10 and HR21 spectra, amounting to 37 565 unique Milky Way field targets. Methods. Cross-correlation functions (CCFs) have been re-computed thanks to a dozen spectral masks probing a range of effective temperatures (3900 K < T-eff < 8000 K), surface gravities (1.0 < log g < 4.7), and metallicities (-2.6 < [Fe/H] < 0.3). By optimising the mask choice for a given spectrum, the newly computed, so-called NACRE (NArrow CRoss-correlation Experiment) CCFs are narrower and allow more stellar components to be unblended than standard masks. The DOE (Detection Of Extrema) extremum-finding code then selects the individual components and provides their radial velocities. Results. From the sample of HR10 and HR21 spectra corresponding to 37 565 objects, the present study leads to the detection of 322 SB2, ten SB3 (three of them being tentative), and two tentative SB4. In particular, compared to our previous study, the NACRE CCFs allowed us to multiply the number of SB2 candidates by approximate to 1.5. The colour-magnitude diagram reveals, as expected, the shifted location of the SB2 main sequence. A comparison between the SB identified in Gaia DR3 and the ones detected in the present work was performed and the complementarity of the two censuses is discussed. An application to the mass-ratio determination is presented, and the mass-ratio distribution of the GES SB2 is discussed. When accounting for the SB2 detection rate, an SB2 frequency of approximate to 1.4 % is derived within the present stellar sample of mainly FGK-type stars. Conclusions. As primary outliers identified within the GES data, SBn spectra produce a wealth of information and useful constraints for the binary population synthesis studies.

The Carina Nebula is an active star-forming region with several open clusters rich in massive OB stars, thus making it an optimal target for studying stellar properties such as rotation for large samples of these early-type stars. We studied a sample of early-type stars probable members of the eight open clusters in the Carina Complex. The observational data consist of high-resolution spectra from the Gaia-ESO public Spectroscopic Survey. Astrometric and photometric data from Gaia EDR3 and radial velocities measured from the observed spectra are used to confirm the cluster members. The projected rotational velocities of 330 early-type stars of Carina are derived from the widths of He i lines at 4388 and 4471 angstrom. The reported V sin i values are the first estimates for 222 early-type stars. The V sin i distribution for the Carina clusters peaks at similar to 100-150 km s(-1), consistent with the distributions for B stars in Galactic clusters. V sin i estimates for stars members of the clusters Trumpler 15, Collinder 228, Collinder 232, and Bochum 11 are presented for the first time in the literature. For a subsample of stars with earlier spectral types from B0 to B3, we find a bimodal distribution, with a third, small peak towards the upper values of V sin i. When the full sample is split according to the parent cluster, we find that the oldest cluster in our sample, NGC 3293, presents a higher concentration of rapidly rotating stars. In contrast, Collinder 228 presents a larger number of stars with lower V sin i.

The properties of binary stars are fundamental for understanding star formation and evolution. Spectroscopic binaries (SB) are genuine binaries that probe short to intermediate orbital periods, shedding light on various stellar evolution pathways. We share recent findings from the Gaia-ESO Survey regarding stellar multiplicity from a statistical point of view. Additionally, we present the binary content of Gaia DR3 and compare Gaia NSS SB with the SB9 reference catalogue of spectroscopic orbits. Finally, we provide insights into the detectability of SB within the context of other large spectroscopic surveys, such as 4MOST, which is set to begin operations next year.

Context. The production of elements heavier than iron in the Universe still remains an unsolved mystery. About half of them are thought to be produced by the astrophysical r-process (rapid neutron-capture process), for which neutron star mergers (NSMs) are among the most promising production sites. In August 2017, gravitational waves generated by a NSM were detected for the first time by the LIGO detectors (event GW170817), and the observation of its electromagnetic counterpart, the kilonova (KN) AT2017gfo, suggested the presence of heavy elements in the KN ejecta. The luminosity and spectra of such KN emission depend significantly on the ejecta opacity. Atomic data and opacities for heavy elements are thus sorely needed to model and interpret KN light curves and spectra. Aims. The present work focuses on large-scale atomic data and opacity computations for all heavy elements with Z >= 20, with a special effort on lanthanides and actinides, for a grid of typical KN ejecta conditions (temperature, density, and time post-merger) between one day and one week after the merger (corresponding to the local thermodynamical equilibrium photosphere phase of the KN ejecta). Methods. In order to do so, we used the pseudo-relativistic Hartree-Fock (HFR) method as implemented in Cowan's codes, in which the choice of the interaction configuration model is of crucial importance. Results. In this paper, HFR atomic data and opacities for all elements between Ca (Z = 20) and Lr (Z = 103) are presented, with a special focus on lanthanides and actinides. In particular, we found increased lanthanide opacities compared to previous works. Besides, we also discuss the contribution of every single element with Z >= 20 to the total KN ejecta opacity for a given NSM model, depending on their Planck mean opacities and elemental abundances. An important result is that lanthanides are found to not be the dominant sources of opacity, at least on average. The impact on KN light curves of considering such atomic-physics-based opacity data instead of typical crude approximation formulae is also evaluated. In addition, the importance of taking the ejecta composition into account directly in the expansion opacity determination (instead of estimating single-element opacities) is highlighted. A database containing all the relevant atomic data and opacity tables has also been created and published online along with this work.

We analyze high-resolution spectra of five carbon-enhanced metal-poor (CEMP) stars acquired using Ultraviolet and Visual Echelle Spectrograph (UVES). Assuming local thermodynamic equilibrium (LTE), we derive the abundances of extreme r-process elements such as Tb, Ho, Tm, and Yb using TURBOSPECTRUM radiative transfer code with MARCS model atmospheres. Four of the program stars have their atmospheric parameters adopted from our previous studies, while for CS 22947-187, we determine the atmospheric parameters (Teff = 5200 K, log g = 1.5, ξ = 1.70 km s−1, and [Fe/H] = −2.55) using the BACCHUS code in semi-automated mode. These stars are already classified as CEMP-rs stars (i.e., carbon-enhanced metal-poor stars with enrichment of elements from both slow and rapid neutron-capture processes), using our new classification criteria for CEMP stars. The derived r-process abundances for our program stars are similar to those for rI and rII stars of similar metallicity.

Aims. Over the past decades, libraries of stellar spectra have been used in a large variety of science cases, including as sources of reference spectra for a given object or a given spectral type. Despite the existence of large libraries and the increasing number of projects of large-scale spectral surveys, there is to date only one very high-resolution spectral library offering spectra from a few hundred objects from the southern hemisphere (UVES-POP). We aim to extend the sample, offering a finer coverage of effective temperatures and surface gravity with a uniform collection of spectra obtained in the northern hemisphere. Methods. Between 2010 and 2020, we acquired several thousand echelle spectra of bright stars with the Mercator-HERMES spectrograph located in the Roque de Los Muchachos Observatory in La Palma, whose pipeline offers high-quality data reduction products. We have also developed methods to correct for the instrumental response in order to approach the true shape of the spectral continuum. Additionally, we have devised a normalisation process to provide a homogeneous normalisation of the full spectral range for most of the objects. Results. We present a new spectral library consisting of 3256 spectra covering 2043 stars. It combines high signal-to-noise and high spectral resolution over the entire range of effective temperatures and luminosity classes. The spectra are presented in four versions: raw, corrected from the instrumental response, with and without correction from the atmospheric molecular absorption, and normalised (including the telluric correction).

Understanding the chemical evolution of galaxies requires accurate abundances of chemical elements in various stellar populations, which are then compared with theoretical predictions to probe their nucleosynthetic origin. However, most of the elements have several stable isotopes which are produced by different nucleosynthetic reactions, thus making multiple contributors to their overall abundance. The situation will be more complex in the case of heavy elements produced by different neutron capture processes. Hence, the abundances at the isotopic levels are more important to constrain the conditions at which the nucleosynthesis takes place and also to identify the actual isotopic path followed by the different neutron capture processes. This will help us identify the relative contribution of different neutron capture processes to the abundance of individual elements, and it is an essential ingredient of the GCE models. Moreover, the contribution of different astrophysical sites, such as AGB stars, to the overall chemical enrichment of our Galaxy can be estimated with greater accuracy. Here we present the preliminary results of our attempt to measure the Eu isotopic abundance in a sample of s-process-enhanced stars at various metallicities. The purpose of this analysis is primarily to demonstrate the feasibility of the technique and a detailed quantitative analysis will be presented in a future paper.

Separating stars enriched in the s- and r-processes of nucleosynthesis is usually achieved by analyzing the element ratios of s-process elements (like Ba or La) to r-process elements (like Eu). The situation becomes more complex when analyzing CEMP-rs stars, which are carbon-enriched metal-poor objects enriched in a mixture of s- and r-elements. These objects, possibly resulting from the i-process of nucleosynthesis, are notoriously difficult to classify based on elemental ratios. Recent theoretical studies have outlined, however, that the s-, i-, and r-processes produce distinct isotopic mixtures. Here, we propose to analyze a sample of stars known to be enriched in s, r, or r + s elements and to determine the odd-to-even isotopic ratio measured on atomic lines of barium, in order to validate or disprove their assignation.

Context. Stellar convection plays an important role in atmospheric dynamics, wind formation, and the mass-loss processes in asymptotic giant branch stars. However, a direct characterization of convective surface structures in terms of size, contrast, and lifespan is quite challenging, as spatially resolving these features requires the highest angular resolution. Aims. We aim to characterize the size of convective structures on the surface of the O-rich AGB star R Car to test different theoretical predictions based on mixing-length theory from solar models. Methods. We used infrared low-spectral resolution (R similar to 35) interferometric data in the H-band (similar to 1.76 mu m) obtained by the instrument PIONIER at the Very Large Telescope Interferometer (VLTI) to image the star's surface at two epochs separated by approximately six years. Using a power spectrum analysis, we estimated the horizontal size of the structures on the surface of R Car. The sizes of the stellar disk at different phases of a pulsation cycle were obtained using parametric model fitting in the Fourier domain. Results. Our analysis supports that the sizes of the structures in R Car are correlated with variations in the pressure scale height in the atmosphere of the target, as predicted by theoretical models based on solar convective processes. We observed that these structures grow in size when the star expands within a pulsation cycle. While the information is still scarce, this observational finding highlights the role of convection in the dynamics of those objects. New interferometric imaging campaigns with the renewed capabilities of the VLTI are envisioned to expand our analysis to a larger sample of objects.

Our purpose is to study the effect of binary companions located within the first 10 stellar radii from the primary AGB star. In this work, we target the mass-losing carbon star V Hydrae (V Hya), looking for signatures of its companion in the dust forming region of the atmosphere. The star was observed in the L- and N-bands with the VLTI/MATISSE instrument at low spectral resolution. We reconstructed images of V Hya's photosphere and surroundings using the two bands and compared our interferometric observables with VLTI/MIDI and VISIR archival data. To constrain the dust properties, we used DUSTY to model the spectral energy distribution. The star is dominated by dust emission in the L- and N- bands. The VISIR image confirms the presence of a large-scale dusty circumstellar envelope surrounding V Hya. The MATISSE reconstructed images show asymmetric and elongated structures in both infrared bands. In the L-band, we detected an elongated shape of approximately 15 mas, likely to be of photospheric origin. In the N-band, we found a 20 mas extension North-East from the star, and perpendicular to the L-band elongated axis. The position angle and the size of the N-band extension match the prediction of the companion position at MATISSE epoch. By comparing MATISSE N-band with MIDI data, we deduce that the elongation axis in the N-band has rotated since the previous interferometric measurements 13 years ago, supporting the idea that the particle enhancement is related to the dusty clump moving along with the companion. The MATISSE images unveil the presence of a dust enhancement at the companion position, opening new doors for further analysis on the binary interaction with an AGB component.