Seminars and Colloquia at ESO Santiago

Mass loss shapes the fate of massive stars, however the physical mechanism causing it remains uncertain. We present a comprehensive analysis of 7 red supergiants in 3 low metallicity galaxies: NGC 6822, IC 10 and WLM, and search for evidence of episodic mass loss. We derived the physical properties of 5 of them using the MARCSatmospheric models corrected for non-local thermal equilibrium effects to measure stellar properties from our new near-infrared spectra, such as the effective temperature, surface gravity, metallicity and microturbulent velocity. We constructed optical and infrared light curves, discovering 2 targets in NGC 6822 with photometric variability between 1 and 2.5 mag in amplitude in r and ∼ 0.5 mag in the mid-infrared. Furthermore, we discovered a candidate dimming event in one of these sources. Periods for 3 red supergiants were determined using epoch photometry. Our comprehensive analysis of all the available data for each target provides evidence for episodic mass loss in 4 red supergiants.

One of the science goals for ESO's forthcoming ELT is to test the universality of the laws of physics, by studying the stability of dimensionless fundamental constants. The method for doing this is based on detailed analyses of high resolution quasar spectra, applying the Many-Multiplet Method. Such measurements are difficult, requiring a combination of laboratory measurements, exquisite calibration of the astronomical spectra, and AI analysis methods taking full account of all potential systematics. These difficulties are justified by the potential reward; a detection of any spacetime change in a fundamental constant would revolutionise physics, whilst upper limits stringently constrain unification models. I will describe recent measurements using ESPRESSO data, and more generally, the overall current status of this subject.

The Asgard visitor instrument brings together four cutting-edge, synergistic tools for the VLTI: HEIMDALLR, a dual-purpose instrument for simultaneous fringe tracking and stellar interferometry in the K band using sensitivity-optimized optics; BALDR, a high-speed (3 kHz) H-band Zernike wavefront sensor for Strehl optimization; BIFROST, a spectroscopic combiner exploring stellar and planetary system formation in the Y-J-H bands; and NOTT, a nulling interferometer designed to image nearby young planetary systems in the L band. Phase 1, starting this weekend, marks the installation of the internal source Solarstein, along with HEIMDALLR and BALDR. We present the collaborative 5-year journey of concept development and team formation, followed by three years of design, construction, and integration efforts across Australia and France since funding began. As the system moves into science operations, we outline our risk mitigation strategies enabled by the visitor instrument pathway and share our vision for engaging the broader community in the next phase.

In this Python Coffee, we’ll explore how TOPCAT (GUI) and STILTS (command-line) help users navigate this data from large scale surveys efficiently enabling fast queries via ADQL/TAP, cross-matching, table manipulation, and visualization. Using real Gaia DR3 examples, we’ll cover how to build queries, clean and subset data, identify stellar populations, and scale workflows with STILTS scripts. Whether you're new to catalog analysis or looking to enhance your toolkit, this session offers a practical introduction to turning big data into astrophysical insight.

By resolving individual molecular lines, high resolution spectroscopy (HRS) of exoplanets can constrain chemical compositions, thermal structure and velocities in their atmospheres. Providing favourable contrasts and large orbital velocities, Hot Jupiters (HJs) have been particularly fruitful targets for HRS, producing high quality datasets in both emission and transmission. Today, a key goal for HRS study of HJs is to robustly extract spatial and dynamical information revealing their 3D structure and climate patterns. Particularly in emission, a significant challenge to this goal lies in the need to sum signal over many phases of the planets' orbits, such that extracted spectra are averaged over the planetary surface. Eclipses, where the planet is progressively hidden/revealed from behind its star, could provide a unique solution for obtaining spatially resolved spectra. While it has been successfully applied at low spectral resolutions to map temperatures on several HJs, eclipse mapping has yet to be attempted with HRS.

In this talk, I will present preliminary results from the first observational campaign to perform high resolution eclipse mapping on the ultra-hot Jupiter (UHJ) WASP-33b. Based on injection-recovery in real data observed through an ongoing large program with SPIRou, we find that 20 eclipses would be required to confidently constrain the planet's rotation and map its CO emission. With a total of 8 eclipses observed so far, we strongly detect the planet's CO emission while it is being occulted, in line with our expectations. These results demonstrate the great potential of eclipses with HRS to map molecules and winds on exoplanets in the near future, paving the way for the upcoming ELT which will be able to perform this on a much wider population of HJs. Additionally, leveraging much shorter time series than typical HRS observations, our analysis yields interesting lessons on optimal stellar correction and pre-processing which could become applicable to slow-moving planets.

The Blanco DECam bulge survey obtained ugrizY imaging of the 200 sq. deg of the Southern Galactic bulge, a pathfinder study that provides a dataset comparable to that of the Rubin survey. We have derived photometric metallicities to 0.2 dex precision for 2.6M red clump giants; the resulting metallicity maps show a striking concentration of metal rich stars to the Galactic plane but no radial gradient. The abundance distribution function is bimodal but not gaussian, changing from a single metal rich peak near the plane to a subsolar distribution 1 kpc below the plane. Matching our red clump sample to Gaia proper motions also gives bulge rotation as a function of metallicity; we also find a ~10 Gyr age for the bulge/bar via a re-analysis of derived ages for microlensed bulge dwarfs.  We will discuss what might be expected from the 4MOST and MOONS investigations of the bulge in the coming years.

Earth, other solar system planets, and the diverse set of discovered exoplanets; the origin of most of these planets can be traced back to circumstellar disc hosted by pre-main sequence stars. Inside these protoplanetary discs, dust is growing 13 orders of magnitude in size to build planets from grains, generally understood to follow a bottom-up process. Both theoretical simulations and observational efforts are piecing together the physical processes at play to do so. The spatial distribution of the disc material over time, the coupling of dust and gas, the effects of the stellar host(s), and the environmental dependencies are examples of processes that shape the disc and the (proto)planet architecture. In this lecture I will sketch the puzzle that is being faced, outline the physics behind, and describe the various observational techniques used to uncover pieces of the planet formation puzzle, focusing on the current big open questions; the where, the when, and the how.

We have installed a new Q-band receiver, the extended-Q band (eQ) receiver, on the Nobeyama 45m radio telescope in 2021. This receiver covers from 30 to 50 GHz, corresponding to ALMA Band 1. The main science targets are (1) Zeeman observations of SO, CS, CCS, (2) mapping observations toward star-forming regions, (3) CO lines from high-z galaxies, and (4) astrochemistry. We completed its commissioning and started science observations.

In this talk, I will present the commissioning results and show some results for star-forming regions. In addition, I will present my scientific results of Q-band line survey toward a pre-cluster clump in the Serpens South cluster-forming regions. 

The observed decline in protoplanetary disc frequency with age across nearby star-forming regions suggests typical disc lifetimes of a few Myr, placing critical constraints on planet formation timescales. Yet, photometric surveys have uncovered pre-main sequence (PMS) stars with evidence of ongoing accretion that appear significantly older than the bulk population in color-magnitude diagrams (CMDs), raising the question of a population of “old accretors.” In the Orion Nebula, such stars occupy CMD positions consistent with isochronal ages ≳10 Myr, yet display infrared excess and strong Halpha emission. Using VLT/X-Shooter, we conducted a detailed spectroscopic analysis of stellar and accretion properties, alongside age indicators like lithium equivalent width, for PMS stars spanning isochronal ages from ~1 to >10 Myr. After correcting for extinction and accretion veiling, we find these stars occupy positions on the HR diagram consistent with a younger population (1–5 Myr), supported by strong lithium absorption and accretion-to-stellar luminosity ratios typical of actively accreting stars. In this talk, I will present our homogeneous study of accretion in the Orion Nebula and demonstrate how accretion can bias CMD-based age estimates. I will emphasize the importance of accounting for this effect alongside extinction when deriving stellar parameters to avoid misclassifying young stars.

Brown dwarfs have been extensively studied in nearby star-forming regions (d < 400 pc). However, theories suggest that high gas or stellar densities, as well as the presence of massive OB stars, may enhance brown dwarf formation relative to stars. To test this, it is crucial to study brown dwarf populations in massive young clusters, which provide dramatically different star-forming conditions. The nearest examples of such clusters are the supermassive star clusters (SSCs) Westerlund 1 and Westerlund 2, each exceeding 30000 Msun in total stellar mass.

As part of the EWOCS (Extended Westerlund 1 and 2 Open Clusters Survey) project, we have obtained deep JWST/NIRCam observations of these clusters. A key goal of this project is to derive their mass functions and assess whether extreme environments influence brown dwarf formation. By combining these results with studies of other massive young clusters led by members of the project, such as Trumpler 14 and RCW 38, we are placing the first robust constraints on the efficiency of brown dwarf formation in such environments.

In this talk, I will present the JWST/NIRCam data products of both clusters, the (sub)stellar initial mass function of Westerlund 1, and the detection and characterization of brown dwarfs in Westerlund 2, enabled by the rich multi-wavelength filter selection. I will also discuss the implications of these results for our understanding of star formation.

The filamentary pattern in which the Universe's matter concentrates, the cosmic web, is predicted by the ΛCDM cosmological model and contains the majority of the universe's matter. Detailed mapping of this interconnected structure of gaseous filaments, galaxies, quasars, dark matter, and voids, is central to a comprehensive understanding of the origin and evolution of our Universe. I will describe recent imaging observations aimed at detecting the cosmic web using the Condor Array Telescope in New Mexico, centered on the Cosmic Evolution Survey (COSMOS) field at a redshift of z=2.45. I will also show new calculations based on hydrodynamical simulations to predict the cosmic web Lyman-alpha emission properties for comparison with real data. Finally, I will discuss the construction of a new Condor Telescope in the Atacama that will go even deeper and which we hope will see first light towards the end of 2025.

Lensed quasars are worthy of receiving telescope time because they look cool ...and alas, also because of the science they enable. Indeed, quasars themselves are extremely bright, making them visible across nearly the entire observable Universe.
When they are also gravitationally lensed, their light travels along different paths through expanding space, accumulating a difference in travelled distance. This difference is measurable and inversely proportional to the expansion rate of the Universe -- the Hubble constant.
The one-step measurement we get from this is very relevant today, as the concordance cosmological model seemingly fails to reconcile the predicted and observed Hubble constant: either the concordance model is insufficient (exciting), or there are unaccounted for systematic errors in the measurements (boring).

But can we truly turn lensed quasars into precision cosmological tools?
In this talk, I will give an update on the technique, "Time Delay Cosmography", with special focus on recent contributions from ESO telescopes.
I will address its primary criticism, how we mitigate it, and present recent results of the TDCOSMO collaboration.

There are at least 100 billion brown dwarfs - substellar objects that do not sustain hydrogen fusion - in our Galaxy. Their masses span from around 80 Jupiter masses down to just a few, encompassing the regime of so-called “free-floating planets.” Several formation mechanisms have been proposed for these objects, including turbulent fragmentation, disk instabilities, and dynamical ejection from planetary systems. Still, their relative contributions remain poorly constrained and likely depend on both mass and environment. Understanding the dominant formation pathway of brown dwarfs and planetary-mass objects, and whether their origins vary with star-forming conditions, is essential for completing our picture of how stars form. This goal requires both a statistical analysis of substellar populations and detailed characterization of individual objects, ideally within their birth environments: young clusters and star-forming regions. In this talk, I will present our ongoing efforts, based on deep imaging and spectroscopic surveys with 8-meter-class telescopes and JWST, aimed at constraining the low-mass end of the initial mass function in a variety of Milky Way environments - from nearby star-forming regions to more distant, massive young clusters. 

The Center for Astrophysics and Associated Technologies (CATA) is Chile’s largest astronomical research consortium, with over 25 years of experience advancing frontier science. This talk will explore CATA’s journey from its origins in fundamental astrophysical research to its current role as a key player in astronomical instrumentation and technology transfer. We will discuss what technology transfer means in the context of astronomy, how CATA has developed the capabilities to turn scientific knowledge into industrial applications, and the mechanisms we use to enable this transformation. Finally, we will address future challenges and reflect on how astronomy can continue to generate positive externalities for society by diversifying the industries it collaborates with — from communications and mining to disaster response and beyond

Although our understanding of low-mass star formation has significantly advanced over the past few decades, the transition from a prestellar core to a protostar remains poorly understood. During this phase, theory predicts the existence of a short-lived and observationally elusive object known as the First Hydrostatic Core (FHSC), which marks the onset of protostellar collapse before nuclear fusion begins. On the other hand, Very Low Luminosity Objects (VeLLOs), sources with internal luminosities below 0.1 L☉, have been proposed as potential FHSC candidates. However, their true nature remains unclear, as they may also correspond to more evolved protostars or even proto-brown dwarfs. As a first step toward distinguishing between these scenarios, we analyzed ALMA archival data for a sample of VeLLOs and FHSC candidates. We focused on identifying molecular outflows traced by CO emission, a first diagnostic of evolutionary stage. When available, we also examined the spatial distribution of other species such as H2CO, CH3OH, HCO⁺, N2H⁺, and deuterated molecules. Our goal is to define and test observational criteria that can help classify whether some VeLLOs may correspond to the FHSC phase. Outflow properties serve as an initial diagnostic, which will be complemented by chemical and temperature tracers in future work.

Mergers are one of the most important drivers of galaxy evolution, as present-day galaxies have been built up over time through hierarchical evolution. The main bodies of galaxies have a diversity of structural properties that can be highly influenced by mergers; unfortunately, the response of a galaxy to a merger largely erases observational markers that allow us to infer the characteristics of the merger. But simulations have shown that material deposited into a galaxy through merger is retained by its stellar halo, thereby leaving a "fossil record" we can trace. In this talk I will discuss my work in harnessing photometry and spectroscopy of resolved stellar populations in nearby stellar halos to understand the impact of mergers in two Milky Way-mass galaxies: M94 and NGC 253. 

Both of these galaxies are unique – M94 hosts the largest pseudobulge in the Local Volume, and NGC 253 is a starburst galaxy with a well-known shell structure in its southern halo. Resolving the halo of M94 to unprecedented depth, we find that M94’s most-massive merger partner was comparable to or smaller in mass than the SMC, suggesting that it had a quiet merger history that did not significantly impact the creation of its pseudobulge. Compared with other MW-mass galaxies, we demonstrate that galaxies with similar merger histories can have very different physical bulge and structural properties. I will also discuss my current work leveraging the power of fiber-fed multi-object spectrographs to make the first-ever measurement of the resolved-star stellar kinematics – line-of-sight velocity and velocity dispersion – in NGC 253’s halo. While this work is still in progress, I will highlight the unique challenges of performing fiber spectroscopy at an extremely low S/N regime and present preliminary results which indicate that the recent merger that created NGC 253’s shell had relatively low angular momentum and may have been on a retrograde orbit.

Study of astrophysical objects requires always more complex models (black hole surrounding, exoplanet atmosphere, accretion disk, galaxy formation and evolution, …) whose inputs imply always more precise measurements. On the other side, the astronomical instruments start to reach their fundamental limits (negligible sensor readout noise, precise mirror polishing, technologies harder to scale up to extremely large telescopes, …). During this lecture, I will discuss how data science applied for optimal data reduction and processing via inverse problem approaches can bridge this gap, by pushing the experimental limits without the need of further instrumental developments. After a few examples on different applications: integral field spectroscopy (SPHERE/IFS), blind deconvolution and PSF reconstruction (SPHERE/ZIMPOL) and extreme adaptative optics (GRAVITY+), we will go through an interactive session with a simple deconvolution problem.

Ever wondered what daily life looks like for a person in wheelchair? How wheelchair-friendly is your workplace? Could you navigate ESO Santiago without problems if you were constrained to use a wheelchair? Accessibility barriers are a constant challenge for people with disabilities, yet many go unnoticed.  Join us for wheelchair day where you will:

• Experience firsthand the challenges of moving in a wheelchair.
• Discuss practical solutions to improve accessibility at ESO.

Raise your voice and be part of the change, because accessibility is also your responsibility!

The fabrication of image slicers remains a key challenge in modern astronomical instrumentation [1]. Traditional techniques, such as diamond turning, are costly and time-consuming, limiting their extensive use in astronomy. Indeed, the high precision needed in both individual slice surfaces and their relative alignment further complicates production. Future large-scale projects, such as the Wide-Field Spectroscopic Telescope (https://www.wstelescope.com/), will require an unprecedented number of these devices, posing a significant challenge for existing fabrication methods.
Ultrafast Laser-Assisted Etching (ULAE) could be a powerful route to manufacture fused silica image slicers, potentially enabling the precision shaping of fused silica over multi-millimeter scales with micron-level precision. Here, we demonstrate the potential of using ULAE for manufacturing image slicers by fabricating a 20-slice prototype, where each 1 mm  15 mm slice is a segment of a 200 mm radius sphere with varying tip and tilt orientations (Figure 1). The alignment between slices is maintained within 10 μm, meeting the stringent requirements for astronomical applications. We are currently in the process of developing in parallel a CO2-laser polishing system to remove the remaining high spatial frequencies roughness left after the etching process [2].
This work highlights the potential of precision laser manufacturing as a cost-effective and scalable solution for fabricating fused silica image slicers, paving the way for their broader implementation in future astronomical instruments.

The Euclid space mission is an M-class mission from ESA launched in July 1, 2023. Its core aim is to cast light on the dark Universe through a combination of weak lensing and baryon acoustic oscillations. While this will, hopefully, be transformational – the combination of near-IR slitless spectroscopy and near HST resolution imaging over 15,000 deg^2 will provide a legacy for decades to come.

In this presentation I will give a brief overview of the Euclid space mission, the core science aims and the data it provides, before delving into the first non-cosmology science results and data releases from the mission. I will in particular discuss what Euclid enables on strong lensing, where Euclid will enlarge the sample of known lenses by two orders of magnitude, as well as the various aspects of galaxy evolution near and far. I will close with a discussion of how you can access the data now and what you can expect in the coming years.

Asteroids aren’t always alone — some have moons like (4337) Arecibo. Understanding these binary systems is key to learning how our solar system formed and evolved, as well as about the internal structure (homogeneity or layering) and composition of asteroids . However, most of these systems remain undetected. Traditional observation methods (e.g. radar or optical lightcurves, adaptive-optics imaging…) miss many of them, creating a biased view of what's really out there. To address this, the GAIAMOONS project was launched in 2023 to identify asteroid moon candidates using data from the European Space Agency’s Gaia mission, and confirm them through stellar occultation — a technique where an asteroid passes in front of a star, briefly blocking its light. So far, 358 candidate systems have been identified, and 51 occultation events observed. One highlight was a major campaign in October 2024 involving 30 observatories across Europe, which revealed a highly detailed shape of asteroid (5044) Shestaka and a positional shift suggesting a companion could be nearby — though not directly detected this time. Other asteroids, such as (35420) 1998AG6 (542) Susanna, and (1127) Mimi, have shown signs hinting at the presence of moons or unusual shapes. These early results already provide significant insights into asteroid systems, demonstrating the effectiveness of stellar occultation as a method. The findings validate its relevance for detecting complex structures and dynamics, and open new perspectives for understanding the formation and evolution of small bodies in our solar system.

Extended linear polarimetry of the light provides unique insights into multiple astrophysical processes in the Universe. We first show a multi-wavelength calibration study of the imaging polarimetric mode of the FORS2 instrument at the VLT, revealing an instrumental polarization pattern that increases radially outwards reaching up to 1.4% at the edges. We then use these techniques and calibrations to study the spatial polarimetry maps for two science cases: i) the active galactic nucleus of Circinus, which reveals consistency with the new paradigm of a dusty hollow cone surrounding the central supermassive black hole and its accretion disc; and ii) nearby supernova host galaxies, whose localized polarization-wavelength relations follow a Serkowski law governed by extinction laws that are on average consistent with the Milky Way value of Rv=3.1, at odds with findings obtained directly from supernova observations.

David Komanek- Re-accretion of wind and supernova matter onto a central black hole

Massive stars which end their life as stellar mass black holes significantly reshape their surrounding interstellar medium (ISM) through fast stellar winds, ultraviolet ionizing radiation, and supernova ejecta. The black holes subsequently form within this modified environment. We explore whether black holes can accrete a significant amount of gas from this environment to explain the origin of relatively massive black holes that have been recently observed by gravitational waves. We present hydrodynamic simulations that incorporate key physical processes, including thermal conduction, radiative cooling, gravity, and radiation transport. We model the properties of interstellar bubbles across a broad parameter space, considering both scenarios where the progenitor star ends its life in a core-collapse supernova and those involving direct collapse into a black hole. Our results demonstrate that a supernova explosion heats the bubble interior so strongly that its cooling time becomes prohibitively long, making substantial accretion onto the black hole unlikely. The scenario with direct collapse seems to be, according to our results, more favorable for gas accretion from the stellar wind bubble. However, even in this case the models we were able to calculate did not result in a significant increase of the black hole mass.

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Supermassive black holes influence their host galaxies during accretion. Super-Eddington accretion—where the rate exceeds the Eddington limit—may have driven rapid SMBH growth in the early Universe. Nearby Narrow-Line Seyfert 1 galaxies (NLSy1s) serve as local analogs of these early systems, offering key insights into black hole feeding and feedback. We studied HE0054-2239, a super-Eddington NLSy1 observed with VLT/MUSE, to search for galactic-scale ionized outflows via optical emission lines. A dominant unresolved nucleus—up to 1000 times brighter than the host—challenged the analysis, so we developed a method to isolate residual narrow components under the nuclear PSF. Our results reveal a fast, unresolved [O III] outflow with no extended emission, suggesting either a young wind or inefficient feedback. Hints of possible inflow in the host’s gas dynamics also emerge but require further confirmation. In the last part of the talk, I will present the brand new XRISM high-resolution X-ray observations of the quasar PDS 456. The data show five ultra-fast wind components (20–30% of the speed of light) in a highly clumpy outflow, with mass loss rates and kinetic power exceeding the Eddington limit—challenging classical feedback models.

 

The FRIPON network is composed of 250 fish-eye cameras to detects fireballs, it measures their position and triangulates it to determine the bright trajectory in the atmosphere. Initially, the aim was to extend the trajectory (dark flight calculation) and thus calculate a strewn field in order to search for a possible fresh meteorite. It is also possible to extend the trajectory into the past to obtain the orbit of the object before it entered the atmosphere. We have 11,000 orbits since the start of the project for objects ranging from 1 cm to a few meters. This is the only method for detecting interplanetary matter in this size range. I'll be showing the iresults of the project, as well as related applications (light pollution measurement, polar auroras, etc.).  Finally, FRIPON is linked to the Vigie-Ciel collaborative science program, firstly to help us search for meteorites, and secondly to disseminate science.

TBD

Forbidden Emission Lines (FELs) map outflow activity i.e. jets and winds, in Classical T Tauri stars (CTTSs). It is an open question as to whether the FEL low velocity component (LVC) traces an magneto-hydrodynamic (MHD) or photoevaporative wind. This question is relevant to excess angular momentum removal in young star. If the LVC is an MHD wind, then it should be linked to the high-velocity component (HVC)/jet. Here, I present the kinematic and spectro-astrometric analysis of the different velocity components observed in the [O I] λ5577 , [O I] λ6300 and [S II] λ6731 forbidden emission lines in three epochs of spectra from the CTTS DG Tau spanning ≈ 20 years in time. DG Tau is a well studied source that has a variable jet that has been significantly decreasing in radial velocity over the ≈ 20 years that our data spans. While the low velocity component also shows some variability over this same period of time, our study reveals that it behaves differently to the HVC which hints at key information about the origin of the LVC. In this talk, I will discuss the significance of the results for DG Tau and how this approach could be applied to other sources to test what variability can reveal about the origin of the LVC.

To date, more than 5500 exoplanets have been detected. Yet, fewer than 300 of them have been found around giant stars. Giant stars, however, are prime targets to explore planetary formation around stars more massive than the Sun. With their cooler temperatures and slower rotation rates compared to their main-sequence counterparts, giant stars are bright, favorable objects for precise radial-velocity measurements. I will present the CORALIE radial-velocity search for companions around evolved stars (CASCADES) survey, initiated in 2006 to detect exoplanets orbiting giant stars. With nearly two decades of observations of 641 G- and K-giants, this survey alone is expected to increase the known population of exoplanets around giant stars by at least 20%.  This survey also provides enigmatic cases, where observed signals may arise from either planetary companions or poorly understood stellar activity. These ambiguous detections highlight the challenges of distinguishing intrinsic stellar variability from genuine exoplanet signatures, offering new insights into the complex behavior of giant stars.

Ever since galaxies were discovered, their morphology has been a key interest for astronomers, who fastly classified them into two major groups: elliptical/lenticular galaxies and barred/unbarred disc galaxies. Notwithstanding, today, we understand that their morphologies and structures are closely linked to their mass assembly history, their stellar populations, and internal dynamics: elliptical galaxies are pressured-supported galaxies that host old stars and experienced many major mergers in the past; on the other hand, disc galaxies have ordered motion, host most of the star formation in the Local Universe, and probably experienced a quiescent merger history. Furthermore, the frequent presence of a stellar bar in disc galaxies indicates a strong internal evolution is taking place. Bars are present in up to 70% of the disc galaxies in the Local Universe, affecting their host galaxy for over 10 Gyr, in some cases. There are different ways they can lead the evolution of the galaxy: redistributing angular momentum, stars, and gas; spatially quenching star formation; and creating structures.

In this lecture, I expect to address different aspects of galaxy evolution and structure formation, focusing on my expertise, which is barred galaxies. Any background of expertise is welcome to join!

TBD

 

 

Omega Centauri is the most massive star cluster in our galaxy and is thought to be the surviving nucleus of the Gaia-Enceladus dwarf galaxy merger. Understanding its formation history would provide insights into the complex abundance patterns seen in GCs with multiple populations. In this work we utilize the oMEGACat, a combined astro-photometric and spectroscopic catalog, to measure ages of >8k SGB stars and the helium enhancement of second-generation stars. We find a wide spread in ages accompanies the large metallicity spread in Omega Cen. Most interestingly, we find a distinct two-stream sequence in the age-metallicity relation, implying at least two formation pathways for the cluster. Follow up FLAMES observations are planned to determine their origins. Additionally, we see rapid helium production at low metallicities, then trends consistent with a flat relation at higher metallicities, suggesting a change in the efficiency of helium production over the cluster’s lifetime. Because helium abundance is a key parameter in stellar population models, this work provides valuable input for constraining the assembly of complex stellar systems.

Perfectionism is not about being one’s best, it is about fear of failure, fear of judgement or the belief of not being good enough. Throughout life, one may feel the pressure of achieving; either from society or from within. Especially in an academic environment, one can feel the need to excel in many levels. When this turns into a (self-)demand of always reaching an extremely high level and doing good feels not good enough, one finds oneself striving for perfection. While it is somehow good to pursue the best person one can be, the urge for over-achieving can feel unattainable with potential destructive consequences. I will open the floor and discuss how to recognise perfectionistic elements, identify the pros and the cons of perfectionism, and run over both personal and literature advice on how to strive for excellence but manage perfectionistic tendencies.

Hot dust-obscured galaxies (Hot DOGs) are a rare class of hyper-luminous, dust-obscured quasars with accretion rates approaching or exceeding the Eddington limit. They are likely in a critical phase of galaxy evolution, where intense AGN-driven outflows exert feedback effects on their host galaxies and subsequently suppress star formation. W2246-0526 at z = 4.6, the brightest known Hot DOG and one of the most luminous objects known in the Universe, serves as an ideal laboratory to study AGN feedback. Previous observations with ALMA have revealed a wealth of interesting properties of this unique target, including that it is in the process of accreting three of its neighboring galaxies and it has a highly turbulent ISM. In this seminar I will be presenting a study based on high spatial resolution observations (~500pc) of the [CII] emission line. The [CII] dynamics is a dispersion dominated system combined with large nuclear outflows. On one hand, by removing the contribution of the outflows, we show that the nuclear velocity dispersion implies the presence of an SMBH with a mass of log (Mbh/M⊙) = 9.80±0.01, and we find that the size of black hole sphere of influence is as large as ~ 2.3 kpc. This constitutes the first time a dynamic SMBH mass is measured by resolving the SoI at z > 2, and highlights that ALMA high-resolution [CII] observations of obscured luminous quasars hold great promise to increase the number of dynamical SMBH mass measurements in very distant galaxies. This is critical for testing indirect single-epoch broad-line mass estimators that underpin AGN-galaxy co-evolution models. On the other hand, our observations reveal spatially resolved, asymmetric nuclear outflows in [CII] with relatively low velocities (400 km/s < Vout <800 km/s) suggesting interaction with a very dense ISM. Despite their low velocities, our analysis shows that W2246-0526 has some of the most powerful outflows known to date. Combining our findings with the previous wealth of knowledge on this target, we conclude that the AGN in W2246-0526 is likely injecting large amounts of energy into its host's ISM, heating it up and, powering galaxy-scale turbulence that may ultimately inhibit star-formation.

The star formation (SF) history of a galaxy is regulated by the availability of its cold gas, which in turn is driven by the balance between material accreting from intergalactic space and gas expelled from the galactic disk. Atomic neutral hydrogen (HI) is an excellent tracer of this process and it can be now explored in depth thanks to the exquisite combined sensitivity and resolution of the MeerKAT telescope. MeerKAT observations also enable us to study the  impact of nearby active galactic nuclei (AGN) from the innermost parsecs to the virial radius, allowing us to identify how AGN change the physical conditions of the ISM, over which timescales, and how the activity is sustained throughout the lifetime of a galaxy. 

I will show a number of recent and ongoing projects from two MeerKAT Large Survey Programs - The MeerKAT Fornax Survey and MHONGOOSE.  Ultra-deep HI observations enable us to probe the cold gas in and around these galaxies to down to very low-column densities N(HI) ~ 5x10^17 cm^-2 and masses M(HI)~10^6 Msun. Integrating this information with observations of the molecular and ionised gas (e.g. ALMA, MUSE), we obtained a complete picture of the multi-phase gas flowing in and out of galaxies and their interaction with the environment. In particular, I will focus on the mechanisms feeding the AGN duty-cycle of powerful radio sources Centaurus A, NGC3100 and Fornax A and on the impact of the nuclear activity on the surrounding medium.

Understanding the origin of stellar initial mass function (IMF) is a central issue in the study of star formation. The past studies of dense cores reported that the slope of the stellar IMF and core mass function (CMF) are consistent, suggesting that the fundamental mass distribution of stars is determined during the early stage of the core formation. However, dense cores have been observed and studied only in the inner part of the Galactic plane (including the solar neighborhood), which has similar metallicity to that of the solar neighborhood. Thus, an important question to address is whether the same relation between the CMF and stellar IMF holds true even in low-metallicity environments. To solve this question, we performed CO and dust continuum ALMA high-resolution (~0.1 pc scale) mapping observation toward a massive star-forming molecular cloud in the outer Galaxy, which has much lower gas density and lower metallicity (~20 % of the solar neighborhood value) than those in the solar neighborhood . As a result, we successfully detected ~0.1 pc-wide filament structures and ~ 0.1 pc-scale dense core structures in the outer Galaxy for the first time. We found that the properties of the filaments and dense cores are similar to those in the solar neighborhood. We also found that the slope of the CMF in the outer Galaxy is similar to that of the universal IMF. These results suggest that the star formation processes in the low-metallicity environment follow a universal law.

The emergence of complex organic molecules in the interstellar medium is a fundamental puzzle of astrochemistry. Targeted observations with ALMA have opened the door to high-sensitivity spectral surveys over wide bandwidths to elucidate the chemical complexity of young stars in a systematic manner. In this talk, I will present an overview and early results from the ALMA Large Program “Complex Organic Molecules in Protostars with ALMA Spectral Surveys (COMPASS).” We performed unbiased line surveys in the 279 to 312 GHz frequency range of 11 nearby Solar-type protostars. The targeted protostars are known hosts of complex organic molecules and sample different natal environments and evolutionary stages. On the path towards identifying myriad complex organic molecules and their isotopologues, in this talk I will focus on studies of methanol, deuteration, nitrogen- and sulfur-bearing molecules. Ultimately, our international collaboration aims to address how much diversity in organic inventories we can expect for emerging stellar and planetary systems.

Supernovae (SNe) have amazed humanity for thousands of years. Modern sky surveys have been discovering hundreds of these transient events every year - a number that will dramatically increase with future transient surveys, such as the LSST. SNe are keen on understanding stellar evolution, besides being a fundamental driver of chemical enrichment and star formation in galaxies. In this lecture, I will present a historical overview of SN discoveries, and describe their formation scenarios and explosion mechanisms. I will go through the main observational properties of the different SN types, such as hydrogen-rich, stripped-envelope, and interacting SNe. I will also describe thermonuclear SNe (or Type Ia SNe) and their usage as standard candles. Finally, I will do an overview of other puzzling cosmic explosions, such as Tidal Disruption Events (TDEs), Gamma-ray Bursts (GRBs), and kilonovae.

The new high-resolution Near-InfraRed Planet Searcher (NIRPS) is now blazing trails at the ESO 3.6-m telescope in La Silla. This ultra-stable, ground-based spectrograph is designed to work in parallel with HARPS to extend the wavelength coverage from optical to YJH bands.
Contemporaneous to JWST observations and preparatory to the mid-infrared ELT era, the NIRPS atmospheric survey leverages on the high spectral resolution to resolve atomic and molecular near-infrared signatures like helium, OH, and biomarkers such as water. 
In this talk, I will present the very first glimpses from NIRPS+HARPS high-resolution transit spectra of the fascinating torrid ultra-hot Jupiter WASP-189b (Vaulato et al. 2025). This exotic world host one of the most blistering and fiery atmosphere known to date. A key highlight of this talk will be the meticulous search for absorption features spanning a broad range of neutral and ionised metals, atoms, and molecular species by (i) painstakingly cleaning the spectra to reveal the pristine planetary signal, (ii) leveraging the instrumental cross-correlation transmission spectroscopy technique to uncover subtle atmospheric signature, and (iii) comparing the obtained results with fine-tuned isothermal atmospheric models. Injection-recovery tests have been run to enable model comparisons and estimate the expected strength of the signals. As cherry on top, atmospheric retrievals gave us quantitative insights into the wealth of species, the relative abundances of refractories and volatiles, the carbon-to-oxygen ratio (consistency with solar?), the climates, and the opaqueness of the atmospheres. The latter astoundingly results in the Fe-to-hydride ratio exceeding equilibrium model predictions by ~0.5 dex impeding the detection of planetary absorption features in the near-infrared transmission spectrum of WASP-189b hinting at an elevated electron density in the upper atmosphere (Vaulato et al. 2025).

 I will review some of the principles guiding our endeavors and narrate some of the processes in the making of Explorando el Wenumapu and Ckunza Universo. Both these Virtual Reality experiences show astrophysical content from modern scientific and Mapuche and Lickanantay origin, and are the result of actual dialogues between expert members of the communities sustaining the world visions we portray.

Have you ever found yourself rewriting the same logic across multiple scripts or struggling to keep track of hardcoded parameters? Good coding habits can save you time and effort by making your code more reusable and adaptable. In this Python Coffee, we’ll explore two essential practices: the Template Method pattern and Configuration Files. The Template Method helps you define a skeleton for your algorithms, allowing you to reuse structure while customizing behavior. Meanwhile, Configuration Files provide a centralized way to manage parameters, keywords, or settings; making your code more flexible and easier to update when requirements change. Join us to explore these simple yet powerful techniques that will help you write cleaner and more efficient code!

Two of our Paranal summer interns will present the results of their Observatory projects conducted between January and February: (1) Automated Quality Control for MOONS (and other instruments) Exposure Time Calculator: This project focuses on developing a tool to automatically validate the outputs of the MOONS (also CRIRES and FORS) Exposure Time Calculator. The tool is designed to enhance data quality control and assess instrument performance, in preparation for the instrument's commissioning later this year. (2) Interactive Finding Charts and Optimized Scheduling for Moving Target Observations: This project involves creating a tool to optimize the observation scheduling of moving objects, such as asteroids and comets and minimize the possibility of contamination from stars and galaxies during observations. Among other things, this tool offers a Graphic User Interface enabling the creation “on the fly” of interactive Finding Charts, with multiple choices of image and source catalogs.

Interferometric observations of submillimeter galaxies (SMGs) have significantly advanced our understanding of the dust-obscured universe. However, modeling the observed properties of SMGs remains a major challenge for hydrodynamical simulations. In this talk, I will discuss the challenges in modeling SMGs and present our results from the new large-volume hydrodynamical simulation, FLAMINGO, which simultaneously reproduces the redshift distribution and number counts of SMGs without requiring a top-heavy initial mass function. I will summarize the properties of SMGs in FLAMINGO and our predictions for the upcoming TolTEC survey. Additionally, I will briefly show our ongoing analysis of the cosmic environment of SMGs.

Have you ever made a script that has facilitated the workflow of your Python projects? Could it benefit not only your peers, but perhaps the science community as a whole? Then you may want to share your code on the Python Package Index, abbreviated as PyPI, to allow others to pip install your work. In this Python Coffee we will go through the steps to package your Python project, from creating an account on PyPI, to creating the necessary files to make your code pip-installable, understanding important terms throughout this process and, finally, pip installing it to test it out.

Nearly 30 years ago, comet 133P/Elst-Pizarro was discovered in theasteroid belt.  Despite having a stable orbit seemingly no different from any other outer main belt asteroid, this object had a tail. Three months and several telegrams later, the cometary nature was confirmed based on a morphology that was best described by continuous mass loss over a period of weeks to months.  Fast forward to today, and a variety of mass-loss mechanisms have been identified in asteroid belt members, including impacts and rotational instability.  But only the so-called "main-belt comets" like Elst-Pizarro repeatedly produce dust near perihelion, suggesting activity driven by water ice

sublimation.  These objects present the exciting possibility that outer belt asteroids can preserve water ice in their interiors over the ~4.5 Gyr lifetime of the Solar System.  However, 15 years of attempts to detect gas around main-belt comets have only returned upper-limits.  That is, until JWST observed comet 238P/Read in 2022. I will review the JWST observations of comet Read and the findings based on them, and hint at cometary science in general from JWST.

Direct observations of the rapid neutron-capture process (r-process), responsible for synthesising approximately half of all elements beyond the iron peak, remain remarkably elusive. The only direct observations we have for the nucleosynthesis of r-process material come from compact binary mergers (aka kilonovae), and to date, only two such events have been observed spectroscopically – AT2017gfo and AT2023vfi. Spectroscopic observations are key to unravelling the composition of the ejected material, since they possess absorption and emission features that can be linked to transitions belonging to a specific atom/ion. For AT2017gfo, a nightly sequence of X-Shooter spectra were acquired (from 1.4 to 10.4 days post-merger), spanning ~300–2500 nm. For AT2023vfi, two JWST NIRSpec spectra were acquired (at 29 and 61 days post-merger), providing spectral information up to ~5000 nm. In this talk, I will present the results of my recent work analysing the spectroscopic observations of both kilonovae. I will focus on highlighting the most likely candidate r-process species that are responsible for producing the observed spectral features in each of these events, and what that implies for r-process nucleosynthesis from compact binary mergers.

Tidal Disruption Events (TDEs) occur when a star is ripped apart by the immense gravitational forces as it approaches a supermassive black hole, producing luminous flares that have been detected in optical, IR, UV, X-ray and radio. TDEs are a relatively recent discovery with only ~100 observed objects. Better knowledge of TDEs will allow us to improve our understanding of accretion physics and black hole growth.

The Vera C. Rubin Observatory will soon begin its 10-Year Legacy Survey of Space and Time (LSST), which will result in a 100x increase in the number of transients (such as TDEs and supernovae) we observe. With this greatly enhanced discovery rate, it will no longer be possible for researchers to manually interpret all the transients discovered. Therefore, we need machine learning methods to prioritise the interesting ones for detailed follow-up.

We will use Zwicky Transient Facility photometry to produce simulated LSST lightcurve data using Gaussian processes, machine learning and existing models. Further methods will be employed to ensure that the data effectively simulates LSST lightcurves. This extensive data set will then be shared with the community.

Whilst there are many clear benefits to LSST, we must give appropriate consideration to some of the negative impacts it may have. The immense scale of data processing required for LSST is expected to produce emissions which far exceed that of previous sky surveys. We aim to conduct a life cycle analysis of LSST to minimise its environmental impacts and to develop policies to guide future projects.

ESO’s Very Large Telescope Interferometer has a history of enabling breakthroughs in astrophysics and instrumentation. The next leap forward is its new visitor instrument: the Asgard Suite of VLTI visitor instruments. It comprises four natively collaborating instruments: HEIMDALLR, an instrument performing both fringe tracking and stellar interferometry with the same optics, simultaneously, in the K band; Baldr, a Strehl optimizer in the H band; BIFROST, a combiner to study the formation processes and properties of stellar and planetary systems in the Y-J-H bands at high spectral resolution; and NOTT, a nulling interferometer dedicated to imaging young nearby planetary systems in the L band. The Suite is in its integration phase in Europe and should start shipping to Paranal in mid-2025 after approval from ESO. In this talk we outline the key science cases of the Asgard instruments and the status of the project.

Magnetic fields play a fundamental role for the interior and atmospheric properties of M dwarfs and greatly influence terrestrial planets orbiting in the habitable zones of these low-mass stars. Determination of the strength and topology of magnetic fields, both on stellar surfaces and throughout the extended stellar magnetospheres, is a key ingredient for advancing stellar and planetary sciences. In this talk I will review magnetic field measurements of M dwarfs, with the emphasis on direct methods based on interpretation of the Zeeman effect signatures in high-resolution intensity and polarisation spectra. I will summarise results of the field strength measurements using Zeeman broadening studies as well as information on the global magnetic geometries inferred from spectropolarimetric observations. The emerging understanding of complex, multi-scale nature of M-dwarf magnetic fields will be discussed in the context of theoretical models of hydromagnetic dynamos and stellar interior structure altered by magnetic fields.

Exoplanets are a common outcome of the star-formation process. Some of the most relevant properties of planetary systems are set during their formation: the number of planets, their mass, composition, and planetary architecture. In this talk, I will focus on what we have learned about planet formation around the most common type of stars: late M-dwarfs and binaries, and how the combination of the latest ALMA, JWST, and VLT observations gives us a full picture of the planet-formation environment.

How shocks driven by Supernova Remnants (SNRs) affect the star formation potential of impacted clouds is still poorly constrained from an observational point of view. In particular, it is unclear whether these shocks can trigger star formation in molecular clouds.  In this talk,  I will show our results on how the shock driven by the SNR W44 affects the star formation potential of the impacted Infrared Dark Cloud G034.77-00.55. Toward this source, we have used ALMA maps of the shock tracer Silicon Monoxide (SiO) to show how the W44 shock plunges into the cloud’s edge and compress the gas to densities consistent with those required to trigger star formation. Hence, we have used IRAM single pointing observations of the J=1-0 and J=3-2 N2H+ and N2D+ transitions to study the D/H ratio across the shocked gas. The D/H ratio measured from N2H+ and N2D+ is a well-known probe of cold and dense gas with the highest potential to fuel star formation. We find that the D/H across the shock front is enhanced by more than a factor of 3 with respect to the inner-cloud material and is consistent with those reported in literature for low-mass starless/pre-stellar sources. The velocity of the dense and cold gas probed by the enhanced D/H is consistent with that of the post-shocked material. Moved by these results, we have used N2H+(1-0) high-angular resolution ALMA maps to investigate the morphology and kinematics of this dense post-shocked gas, with the aim to identify evidence of early-stage star formation induced by the shock. We find that, the N2H+(1-0) emission is distributed into two elongated structures, both corresponding to H2 mass surface density enhancements. The two elongations show a fragmented morphology characterized by the presence of multiple core-like structures. These cores have spatial scales consistent with the Jeans lengths, masses ∼1-20 M⊙ and densities n(H2)≥10^5 cm−3 i.e., sufficient to host star formation in a free-fall time scales of few 104 yr. Moreover,  the cores have virial parameters that hint toward possible collapse. Hence, we suggest that the W44 driven shock may have swept up the encountered material which is now seen as a dense ridge, almost detached from the main cloud, and an elongation within the inner cloud, well constrained in both N2H+ emission and H2 mass surface density. This shock compressed material may have then fragmented into cores that are either in a starless or pre-stellar stage. Additional observations are needed to confirm this scenario and the nature of the cores.

Chile’s Atacama Desert is home to one of the world's highest densities of meteorites, yet their significance as cultural and scientific heritage remains underappreciated. Supported by a Meteoritical Society Community Grant, the itinerant exhibition "Meteorites: Human Heritage" was created to raise awareness about the importance of meteorite research, their preservation as national heritage, and the scientific insights they provide about the formation and evolution of the Solar System. Through a series of infographics and real samples, the exhibition has reached over 3,500 visitors across multiple regions, engaging diverse audiences in understanding the relevance of meteorites in both Chilean identity and planetary science.

Protoplanetary disks set the initial composition of future planetary systems. Comparing the chemistry of disks to the compositions of exoplanet atmospheres informs our understanding of the planet-formation process. This is the main focus of the ALMA Disk-Exoplanet C/Onnection (DECO) large program. It observed 80 disks across four star-forming regions sampling a range of stellar masses, disk sizes, and environments. During this talk, I will focus on the dust continuum emission of the DECO sample. We fit the continuum visibilities of the dust emission to extract the highest angular resolution from the data and thus constrain the system geometry, dust morphology, disk radii, and presence of substructures. Comparing these results with the disk chemistry found in this survey will revolutionize our understanding of the chemical diversity occurring in more "typical" disks and how it imprints on the diversity of exoplanet populations.

After a short introduction to the concept of light pollution and  its environmental impact, the presentation will focus on tools developped by prof. Aubé to monitor and help to mitigate light pollution. These tools are focussed on the study of both direct light pollution (obtrusive light) and the artificial light scattered in the atmosphere (sky brightness).

Stellar counter-rotation (CR) is a phenomenon where a significant fraction of stars rotate in the opposite direction to the main disk. Counter-rotating stars are believed to form from external gas accreted onto a galaxy with angular momentum opposing that of the main galactic disk. Examining the stellar population properties in such systems provides a unique opportunity to uncover details of external gas accretion. In this talk, I will present a study of CR galaxies identified in the MaNGA survey and the results of dedicated follow-up investigations of these systems.

To strengthen scientific culture, we must measure the effectiveness of science communication strategies. It is not enough to develop outreach activities and products; its also necessary to evaluate their impact and results. For this, it is crucial to establish indicators according to the specific objectives we seek. This allows us to identify both intended and unintended outcomes, make informed decisions, and communicate results effectively to our organization (or ourselves). These insights are crucial for improving accountability, refining strategies, and maximizing impact. This talk will deep into why its important to evaluate, introduce the audience into types of evaluation and what has ESO COMM Chile learned form the evaluation of our initiatives so far.

Low-mass galaxies are the building blocks of massive galaxies in the framework of hierarchical structure formation. To enable a detailed study of their galactic ecosystems by spatially resolving different galactic components, we conducted the Dwarf Galaxy Integral-field Survey (DGIS) using VLT/MUSE and ANU-2.3m/WiFeS. The sample comprises 65 dwarfs at a spatial resolution of 10-100 pc. Based on the high spatial resolution and signal-to-noise ratio data, we applied the spatial two-point correlation function to describe the two-dimensional metallicity distribution in dwarf galaxies. Compared to spiral galaxies, metallicity in dwarf galaxies clustered on smaller scales, with a typical correlation length of around 135 pc.   We found that star formation, instead of stellar mass, plays a key role in regulating metal distribution in dwarf galaxies, in contrast to the expectation from the stellar mass-metallicity relation in integrated galaxies.

Astronomy, while focused on phenomena far beyond Earth, also holds significant relevance for the societies we inhabit. Many astronomers are not only dedicated to studying the cosmos but are equally committed to addressing social issues within their discipline.

Since the early 20th century, an increasing number of scientists have combined academic research with activism, advocating for the inclusion of underrepresented groups such as women, racial and ethnic minorities, LGBTQIA+ individuals, and people with disabilities. Through conferences, publications, and outreach, these discussions are beginning to feature more prominently in most astronomy research settings around the world, but such conversations were not always so commonplace.

In a collaborative effort between ESO, ALMA, SOCHIAS, AUI/NRAO and various Chilean institutions we have organized a mini-workshop aimed at promoting Diversity, Equity, and Inclusion (DEI) within the Chilean astronomical community.

The primary focus of the workshop are:

• Raise awareness  and assess the current state of DEI within the Astronomical community in Chile: Highlight the importance of recognizing diversity and fostering inclusion in Chilean astronomy to create a more  accessible, innovative and collaborative research environment.
• Share and evaluate initiatives from universities and observatories: Review existing DEI initiatives to understand what strategies are effective and where gaps remain, fostering a collective learning process.
• Discuss the future direction of DEI initiatives: Explore long-term strategies and goals for advancing DEI efforts in Chilean astronomy, ensuring sustainable progress and measurable outcomes.

Advancing DEI is not only a matter of social justice but also essential for ensuring high-quality science. By fostering diverse perspectives, the field of astronomy can reach its full potential, driving both innovation and excellence

With Kepler, TESS, and PLATO, asteroseismology has much potential to provide masses for large samples. However, the scaling relation method assumes all stars have internal structures homologous to the Sun. Since this assumption is unrealistic, masses obtained via asteroseismology need to be verified, and the scaling relation needs to be calibrated with model-independent mass measurement. This calibration currently rests on a sample of only 17 “benchmark” binaries, where seismic masses and dynamical masses are available. All existing benchmark stars are on the Red Giant Branch (RGB), and no benchmarks in the main sequence, subgiant, or red clump stage.

In this talk, I introduce an accurate method to measure model-independent stellar masses by observing Gaia binaries using long-baseline interferometry on VLTI and CHARA arrays. By combining a single interferometric epoch around 30 minutes with Gaia photocenter orbits, the full-3D orbits, dynamical masses, and precision ages of both components can be derived. I discuss the method in detail and compare the asteroseismic and dynamical masses for the first Gaia binaries observed. Our method could provide benchmark stars in a much more efficient way and those at different evolutionary stages for the first time. In the end, I aim to use the derived masses to calibrate the scaling relations and the revised scaling relations to calibrate the published asteroseismic mass measurements, maximizing the outcome of TESS and upcoming missions like PLATO.

One powerful capability of ALMA is to observe a project with multiple arrays, including 12m, 7m, and Total Power.  This is important for the science cases that require the recovery of emission on a range of spatial scales.  Some examples include accretion and ejection processes that regular star formation, and molecular clouds distributed throughout galactic environments. Several methods exist to combine the interferometry and single dish data.  In this talk, I will guide the audience in a hands-on demonstration of data combination using the primary CASA methods: Feather and Sdintimaging.  Additionally, we will run through a Jupyter Notebook created for assessing the quality of the combined image(s).  Such quality assessment may be useful for other imaging cases as well, and the entire process should help to inform the development of "group level" processing at ALMA in the future.  All scripts, example datasets, and more materials are available from the recent workshop on data combination for the EU ARC nodes in October 2024: https://arc.ira.inaf.it/events/array-combination-workshop/.  Please feel free to come with any level of data combination experience (including none!), and questions are welcome. I aim to make this presentation informative and relatively informal.