Abstracts

The s-process at Subsolar Metallicity: Insights from High-Resolution Infrared Spectroscopy of Magellanic Cloud Planetary Nebulae

N. C. Sterling, M. G. Stephenson, Harriet L. Dinerstein, A. Yagüe-López, Kyle F. Kaplan, J. Beaumont, Maria Lugaro, Amanda I. Karakas, Umberto Battino, J. García-Rojas, and Samuel M. H. Erben

We present observations of 12 Magellanic Cloud planetary nebulae (PNe) obtained with the high-resolution near-infrared spectrometer IGRINS on Gemini South. In 10 targets we detect multiple neutron(n)-capture elements that can be synthesized by the s-process during the preceding asymptotic giant branch (AGB) phase, including the widely-observed species Se and Kr, and first detections of Rb, Cd, and Te in extragalactic PNe. The derived abundances significantly expand the inventory of trans-iron element abundance determinations from PNe in subsolar metallicity stellar populations. Seven targets exhibit s-process enrichments relative to the metallicity references O and Ar, with abundances elevated by factors of up to 40-50 for Te and Kr. We compare these results with AGB nucleosynthesis predictions, using a machine-learning algorithm to find the best-fitting Monash, FRUITY, and NuGrid models. For five of the PNe, Monash and FRUITY models with 2-4 solar masses and metallicities from 1/3 solar to near-solar match the observations well, although the Monash models more successfully fit the largest Kr enhancements. NuGrid models predict smaller s-process enrichments than observed, but the limited number of available models makes it difficult to assess their ability to reproduce the observed abundances. We were unable to find models that provide good fits to three other enriched PNe, including the most metal-poor objects in our sample. These comparisons address uncertainties in mass loss, convection, and other mixing mechanisms during the late evolution of low- and intermediate-mass stars, and improve the accuracy of s-process yields of AGB stars, which are key parameters for modeling galactic chemical evolution.

Reference : 2026, arXiv:2607.28729 (accepted for publication in ApJS
URL : https://arxiv.org/abs/2607.28729

HST observations of chromospheric UV lines in the AGB star R Leo: I. C ii] multiplet and Mg ii h & k lines

Saberi, Maryam, Luttermoser, Donald G., Harper, Graham M., Khouri, Theo, Uitenbroek, Han, Vlemmings, Wouter

The role of stellar chromospheres in the chemistry, mass loss, and evolution of cool evolved stars remains poorly understood. We present high-resolution ultraviolet spectra of the nearby Mira-type AGB star R Leo obtained with STIS on board the Hubble Space Telescope. We focus on two strong chromospheric diagnostics, the Mg II h and k resonance lines and the C II] 2325 Å multiplet, and model their formation with the NLTE radiative-transfer code RH using phase-dependent hydrodynamic atmospheric structures that include pulsation-driven shocks. The observed C II] multiplet ratios imply an electron density of order 10^9 cm^-3. The RH contribution functions show that the C II] emission is strongly localized in a compact shock-heated shell at the first temperature peak of the model atmosphere, near R ≃ 1.8 R_phot, where T ∼ 10^4 K and the local electron density is a few 10^8 cm^-3. In contrast, the Mg II h and k lines probe a more extended region (R < 16 R_phot), with the line cores forming at greater radial distances than the wings. The Mg II h line is reproduced more reliably than the k line, which is more strongly affected by circumstellar and interstellar absorption. As an additional low-opacity kinematic check, the semi-forbidden Al II] λ2669 line shows a projected stellar-rest-frame blueshift of ∼6 km s^-1, consistent with shock-related motions expected in Mira atmospheres. Overall, the compact C II] formation region, the extended Mg II contribution functions, and the strong phase dependence of the synthetic Mg II profiles support a picture in which pulsation-driven shocks shape the ultraviolet chromospheric emission lines in Mira variable stars.

Reference : Accepted to Astronomy & Astrophysics
URL : https://arxiv.org/abs/2606.07294

Empirical H- and K-band Limb Darkening for 31 CHARA Stars: A Near-Infrared Benchmark for Stellar-Atmosphere Models

Anugu, Narsireddy, Monnier, John D., Mérand, Antoine, Flores, Becky, Gallenne, Alexandre, Gies, Douglas R., Gutierrez, Mayra, Klement, Robert, Kraus, Stefan, Rajagopal, Jayadev, Roettenbacher, Rachael M., Schaefer, Gail H.

Limb darkening, the decrease in stellar intensity from the disk center to the limb, encodes the temperature structure and opacity of stellar atmospheres. Direct spatially resolved measurements of this center-to-limb variation remain scarce, especially in the near-infrared. We present interferometric limb-darkening measurements for 31 stars observed simultaneously in the H and K bands with the CHARA Array. The sample spans spectral types F—M and luminosity classes IV—I. The targets are well resolved in H and, for most targets, also in K. This coverage constrains the visibility curvature associated with limb darkening in joint H+K fits. We fit the combined H+K squared visibilities with four analytic limb-darkening laws and compare the resulting coefficients with bandpass-matched predictions from five stellar-atmosphere grids (Kurucz, MPS1, MPS2, Stagger, and spherical SATLAS, with reported coefficients placed on the Rosseland-radius convention) spanning one-dimensional plane-parallel, three-dimensional radiation—hydrodynamic, and spherical low-gravity models. The associated limb-darkened angular diameters are measured with median formal precisions of 0.2—0.3%. The CHARA results show expected weaker limb darkening at longer wavelengths and also with increasing Teff. The clearest discrepancy with the atmosphere grids is in the wavelength dependence: the median fractional decrease in the power-law coefficient from H to K is 39% in the CHARA sample, compared with only 17—22% with model predictions. Relative to the MPS2 comparison, the empirical coefficients are higher by 21% in H and lower by 5% in K. These results provide multi-band interferometric limb darkening as a near-infrared benchmark for stellar-atmosphere models.

Reference : 2026 Accepted for publication in The Astronomical Journal; 16 figures, 6 tables and 28 pages
URL : https://arxiv.org/abs/2607.24956

Dust production in the harsh environment of Sgr A*- MIRI/JWST observation of the O-rich asymptotic giant branch star IRS 3

F. Peißker, M. García Marín, A. Eckart, G. Wright, O. C. Jones, D. Dicken, A. Alonso Herrero, D. Rouan, D. Law, T. Böker, T. Henning, M. Baes, A. Labiano, L. Pantoni, L. Hermosa Muñoz, P. O. Lagage, P. van der Werf, G. Östlin, J. A. D. L. Blommaert, M. Güdel and P. Guillard

Studies of the interstellar medium (ISM) have frequently revealed signatures of the dust produced in the envelopes of asymptotic giant branch (AGB) stars, demonstrating a connection between the dust composition of the ISM and that of AGB stellar envelopes. Investigating this relationship in the extreme, radiation-dominated environment surrounding Sgr A*, the center of our own galaxy, reveals how such conditions might influence dust composition and the recycling of material in galactic centers.
IRS 3, the brightest L band source in the Galactic center and most prominent AGB star within the inner parsec of the Milky Way, is embedded in a dusty envelope with an estimated radius of ∼10000 AU. We aim to conduct a comprehensive spectral analysis to more tightly constrain the dust composition and line-emitting species within the envelope of IRS 3 in the immediate vicinity of Sgr A*.
In 2025, we observed the inner parsec of the Milky Way with the Mid-Infrared Instrument (MIRI) on board the James Webb Space Telescope (JWST) as part of the guaranteed time observations (GTO) program Mid-Infrared Characterisation of Nearby Iconic galaxy Centres (MICONIC). We used the MIRI Medium Resolution Spectrometer (MRS) to study the spectroscopic characteristics of the AGB star IRS 3, located about 0.17 parsecs in projection from Sgr A*.

Reference : A&A, Volume 712, August 2026, A79
URL : https://www.aanda.org/articles/aa/full_html/2026/08/aa60243-26/aa60243-26.html

A catalogue of high angular resolution and contrast polarimetric maps of 45 nearby AGB stars with SPHERE/ZIMPOL

Nekolgne Aymard Badolo, Eric Lagadec, Mamadou N’Diaye, Sie Zacharie Kam, Iain McDonald, Alexis Matter, Jean Koulidiati, Lyu Abe, Marcel Carbillet, Thierry Fusco

We present the largest catalogue of asymptotic giant branch (AGB) stars, 45 targets in total, observed in polarized light at high angular resolution ( 20 milliarcsec). The main goal of the study is to detect and characterize dust shells in the close environment of nearby AGB stars. This work also aims to systematically classify the AGB star circumstellar morphologies obtained with the SPHERE instrument installed at the Very Large Telescope (VLT), thanks to its Zurich Imaging Polarimeter (ZIMPOL). We extracted and analyzed polarized intensity maps for 45 AGB stars, constructed from polarimetric observation data obtained with the SPHERE/ZIMPOL instrument. An ellipse fitting method was applied to characterize the circumstellar envelopes. Stellar parameters (luminosity, effective temperature, surface gravity, extinction, metallicity) were compiled and recalculated when necessary from spectral energy distribution (SED) fitting using the Python SED fitting tool (PySSED) software. These data were then used to train a random forest machine learning model to determine the most discriminating variables for a resolved envelope around a given star. We constructed polarization maps for all stars in the sample, revealing a wide diversity of circumstellar morphologies. We detected 16 dusty circumstellar envelopes, including three never observed before. They display a wide range of morphologies, all of them showing a clear departure from spherical symmetry, indicating interaction with a companion or asymmetric mass ejections. The random forest model identified optimal thresholds for several physical parameters, thus providing robust criteria to anticipate SPHERE’s ability to resolve dust envelopes around AGB stars. These results facilitate the selection of targets for future observations and contribute to a better understanding of the evolution mechanisms of circumstellar envelopes.

Reference : accepted in A&A
URL : https://arxiv.org/pdf/2608.02410

New Spatially Resolved Observations of Betelgeuse from the VLA and ALMA: Evidence for Atmospheric Perturbations from a Close Companion

Matthews, L. D., Dupree, A. K., Richards, A. M. S., Dent, W. R. F.

We present new spatially resolved observations of the red supergiant Betelgeuse ($α$ Orionis) at seven frequencies: 22 GHz ($λ$1.4 cm); 44 GHz ($λ$6.8 mm); 107 GHz ($λ$2.8 mm); 136 GHz ($λ$2.2 mm); 224 GHz ($λ$1.3 mm); 338 GHz ($λ$0.89 mm); and 485 GHz ($λ$0.62 mm) using the Karl G. Jansky Very Large Array and the Atacama Large Millimeter/submillimeter Array. These observations (spanning 2021-2026) enable a characterization of the mean brightness temperature ($T_B$), shape, and symmetry of the star’s extended atmosphere. At 22 GHz and 44 GHz $T_B$ has increased following the historic lows observed in 2019, just prior to the Great Dimming of late 2019/early 2020. We find that $T_B$ peaks at a larger projected radius ($r\sim2.7R_\star$) compared with measurements prior to 2016, consistent with a possible evolution in the atmospheric density profile. In addition we find a systematic decrease in $T_B$ from $\approx3500$K at $\sim2.7R_\star$ to $T_B\approx$2220K at $\sim1.2R_\star$, confirming a previously reported temperature minimum between the photosphere and chromosphere. At all observed frequencies $T_B$ is lower than temperatures inferred from ultraviolet measurements at comparable radii, indicating the continued presence of cooler plasma ($T\le T_\rm eff$) mixed with the warmer chromospheric material. The new measurements yield a global spectral index $α=1.35\pm$0.03, with no evidence for a change in $α$ over more than two decades in frequency. Recently, evidence of a close-in companion to Betelgeuse has been reported, with an orbital separation $r\sim2.3R_\star$. We have identified a correlation between the ellipticity of Betelgeuse, as obtained from radio measurements, and the companion’s orbital phase. The results are consistent with periodic perturbations of the atmosphere by the companion.

Reference : 2026 23 pages, 13 figures, 6 tables. Accepted to the Astronomical Journal
URL : https://arxiv.org/abs/2608.02847

ALMA high resolution observations of Betelgeuse: Persistent structure spanning the inner atmosphere

Dent, W. R. F., Richards, A. M. S., Harper, G. M., Matthews, L. D., O’Gorman, E.

The extended atmosphere of red supergiants (RSGs) forms an important link in the process of mass loss and the subsequent enrichment of the interstellar medium. Large-scale convection is thought to play a significant role, which is likely to result in irregularities in the surface. High resolution, high contrast sub-mm images of Betelgeuse - one of the closest RSGs - are used to probe the structure and temporal stability of the inner 1-2R* of its atmosphere. Using ALMA in the longest baseline configuration, continuum emission and lines of SiO and CO and their isotopomers were observed at λ0.6-1.4mm, giving beamwidths down to 7mas at the shortest wavelengths. These were compared with a similar observation taken at 0.9mm approximately 7 years earlier. The observed continuum emission arises mostly from an optically-thick mm/sub-mm photosphere of radius 1.1-1.3 R* with a relatively constant temperature of 2300K, but with two hotter patches to the NE and SW. The brightest of these has a temperature enhancement of 800K, and its location and intensity appears relatively unchanged since the 2015 observation. The sub-mm photosphere shows deviations of up to +/- 6% in radius, with weaker continuum extending out to 2.5 R* - similar to the extent of clumpy emission in SiO and CO. The hot regions of gas and deviations from radial symmetry are thought to be associated with active shocks driven by underlying convective cells, although their lifetimes appear longer than model predictions. They lie near the proposed poles of the star, which might suggest enhanced and relatively stable polar convection. The present data show no clear evidence for stellar rotation in the extended line emission or absorption against the photosphere, although the structure of the gas emission has changed significantly since 2015.

Reference : Astronomy & Astrophysics, accepted
URL : https://arxiv.org/abs/2608.19339

Can circumbinary discs produce the eccentricities of shell-burning stripped giant binaries?

Moltzer, C. A. S., Pols, O. R., Van Winckel, H.

Post-RGB and post-AGB binaries, collectively shell-burning stripped giant (SBSG) binaries, contain a primary star recently stripped of its envelope, alongside a main-sequence companion. These systems are characterised by a stable circumbinary disc (CBD), thought to have formed from envelope material stripped via mass transfer. Their eccentricities range between $0-0.63$, contradicting canonical binary evolution that predicts such post-mass-transfer systems should have circularised. We investigate whether CBD-binary interaction can explain the observed eccentricities of SBSG binaries using a new formalism based on hydrodynamic simulations. To compare with observations, we generated model populations for which post-mass-transfer eccentricity and amount of mass accreted from the CBD were free parameters. We found that CBD-binary interaction can reproduce the observed eccentricity distribution of SBSG binaries, provided that: (1) their post-mass-transfer eccentricities range up to at least 0.05, (2) their CBDs have initial masses of at least $0.1$ $M_\odot$, and (3) accretion onto the SBSG star is highly inefficient to prevent refilling of its Roche lobe. Our model requires higher post-mass-transfer eccentricities than canonically predicted and more massive CBDs than currently observed. We speculate that there is a population of post-mass-transfer progenitor systems with CBDs massive enough to facilitate significant eccentricity pumping. Mass loss via the $L_2$ point during mass transfer needs investigation, as this could form the CBD and shorten the orbital period, necessary for many SBSG binaries assuming they formed stably. We hypothesise that the observed eccentricities are related to the amount of mass lost via $L_2$. Since many other post-interaction systems exhibit similar orbital properties, we speculate that they may all have interacted with CBDs shortly after mass transfer.

Reference : 2026 Accepted for publication in Astronomy & Astrophysics. 17 pages, 14 figures
URL : https://arxiv.org/abs/2608.25762

The Hot, Continuum-compact State of the Yellow Hypergiant V509 Cassiopeiae: CHARA Diameters, CO-band Angular-extension Constraints, and Companion Limits

Narsireddy Anugu, Gail H. Schaefer, Douglas R. Gies, Anni Kasikov, John D. Monnier, Stefan Kraus, Karolina Kubiak

Yellow hypergiants are rare, evolved massive stars generally interpreted as post-red-supergiant objects evolving blueward through or near the dynamically unstable Yellow Evolutionary Void. V509 Cassiopeiae is a remarkable example: its spectroscopically inferred effective temperature increased from approximately 5000 K in the mid-1980s to about 7900 K by the late 1990s and has since remained near this value during its post-heating state. We use simultaneous six-telescope CHARA observations obtained in 2023 with MIRC-X in the H band and MYSTIC in the K band to measure its photospheric diameter, search for a luminous companion, and constrain any spatially extended CO atmosphere. Interferometric data fitting with fixed atmosphere-model center-to-limb variation profiles yield limb-darkened angular diameters of 1.1840—1.1950 mas. Although nominally about 5\% smaller than the previous Palomar Testbed Interferometer measurement, the difference is only 1.8σ, indicating no significant secular change over 17—21 yr. The closure phases are consistent with a centrosymmetric brightness distribution, and no near-infrared-bright companion is detected over the sampled separations. The median 3σ limits are ΔH=5.28 mag and ΔK=6.48 mag. The B1 V companion proposed from ultraviolet spectroscopy is expected to lie below these limits and is not excluded. The CO first-overtone channels give a weighted mean CO-to-continuum diameter ratio of 1.011±0.004, below the adopted 3σ detection criterion. We find no significant CO-band angular extension. V509 Cas is thus hot and molecularly compact despite retaining spectroscopically visible atomic circumstellar gas.

Reference : Accepted for publication in The Astrophysical Journal
URL : https://arxiv.org/abs/2608.28829

The Rotational and Magnetic Properties of Polaris from Long-term Spectropolarimetric Monitoring

James A. Barron, Gregg A. Wade and Colin P. Folsom

Polaris is a highly unusual Cepheid with observed properties that are difficult to reconcile with stellar evolutionary models. Since the initial detection of Polaris’ magnetic field in 2020, we have conducted a magnetic monitoring campaign with the ESPaDOnS spectropolarimeter at the Canada-France-Hawaii Telescope. We compute Stokes V least-squares deconvolution profiles and measure the associated mean longitudinal magnetic field strengths Bz. The surface magnetic field has remained remarkably stable over five years of observations, with Bz varying between approximately -3 G and +0.6 G. From the periodic modulation of Bz we infer a stellar rotation period of Prot=100.29+/-0.19 days. This is the first direct measurement of Prot for a classical Cepheid. Previous interferometric radius measurements and Prot imply an equatorial rotation velocity of veq=23.3+/-0.2 km/s. We set a conservative upper bound on the projected equatorial rotational velocity of vsini < 13.5 km/s and constrain the stellar inclination angle to be i < 37 deg. Using the previously determined orbital solution, we find a high likelihood of a strong spin-orbit misalignment. We determine the lower bound on the obliquity angle between the stellar rotation and orbital axes to be beta>18.7 deg at 99% confidence. We discuss the challenges in interpreting the origin and properties of the surface magnetic field in the context of Polaris’ uncertain evolutionary history and the merger hypothesis.

Reference : 2026, The Astrophysical Journal, 1005, 112
URL : https://iopscience.iop.org/article/10.3847/1538-4357/ae77f9

The chemical fingerprint of the Gaia BH3 system. Evidence for early cluster enrichment from the analysis of 51 elements

Broeck, Gregory Vanden, Merle, Thibault, Mai, Nhat Tan, Van Eck, Sophie, Goriely, Stephane, Siess, Lionel, Jorissen, Alain, Hoai, Do Thi

The Gaia BH3 system hosts the most massive known stellar-origin black hole and a low-mass metal-poor companion whose chemical composition may constrain early explosive nucleosynthesis processes. We investigate the chemical abundances of the companion in order to constrain the formation of this remarkable system. We perform a detailed analysis of high-resolution ESO-UVES spectra of the companion. 51 elements from lithium to uranium were investigated through spectral synthesis, including 15 treated in NLTE. We compare the resulting pattern to r-process enriched stars, to nucleosynthesis models and to stars of the ED-2 stream. The abundance pattern of the BH3 companion is consistent with that of r-I stars and is well reproduced by a combination of core-collapse supernova yields and an r-process component. The chemical patterns of four ED-2 stars closely match that of the companion especially when a dilution is taken into account. The present analysis provides the most detailed chemical characterisation of a metal-poor star associated with a stellar-mass black hole. The chemical similarity with ED-2 stars argue against local pollution across the binary system. The abundances instead reflect early spatially inhomogeneous enrichment of the progenitor cluster.

Reference : 2026 Accepted in A&A Letter on 16/07/2026
URL : https://arxiv.org/abs/2605.02353

Annoucements

PhD position in astrochemistry and machine learning at University College Dublin

We invite applications for a PhD position in astrochemistry and machine learning at the School of Physics at University College Dublin, Ireland. You will work with Dr Marie Van de Sande on the ERC Starting Grant ASHES on dust formation in the outflows of asymptotic giant branch (AGB) stars.

Project background
Stars like our Sun will go through an AGB phase near the end of their lives, losing their outer layers by means of a stellar outflow and enriching the interstellar medium with the building blocks for the next generation of stars and planets. To study how the chemistry is affected by the dynamics of the outflow, 3D hydrochemical models are essential. Machine learning is crucial to make this possible: by emulating, rather than calculating the chemistry, an on-the-fly hydrochemical model can finally be built.

What you will do
You will optimise the proof-of-concept emulator MACE by postprocessing Phantom SPH models of AGB binary interactions. While generating the training dataset using snapshot models, you will already be able to determine how different binaries affect the outflow’s chemistry. Coupling the emulator to Phantom, your on-the-fly hydrochemical model will then demonstrate how chemistry is affected by the dynamics. In the next stage, you will train the emulator on a novel chemical reaction network that includes dust formation. This will give us the first 3D and time-dependent overview of how dust formation is affected by AGB stars and their companions.

As part of ASHES, you will interact with all aspects of astrochemistry: chemistry, computational modelling, and astronomical observations. You will start alongside another PhD student, with two postdocs joining the group later. There are ample opportunities for attending conferences, workshops, and research stays.

Who we are looking for
The project is suitable for a student with a degree in physics or astronomy and a genuine interest in building skills in coding (Python and Fortran), machine learning, data analysis, and visualisation. Prior experience in chemical modelling or hydrodynamical modelling is a strong advantage, but not a strict requirement.

Application instructions
Applications should include a CV (including personal data, education, skills, and expertise), a one-page motivation letter, and the names and contact details of two references. Please send the documents to marie.vandesande@ucd.ie before 1 October 2026.

More information: https://marievds.github.io/jobs.html

ESO/ALMA Fellowship Programme 2026 / 2027

ESO’s prestigious postdoctoral fellowship programme in both Garching (Germany) and Santiago (Chile) offers outstanding early-career scientists the opportunity to further develop their independent research programmes. From exoplanets to cosmology, observational, theoretical and fundamental astrophysics, these are all areas where ESO Fellows can benefit from a highly dynamic scientific environment, at some of the most advanced ground-based telescopes in the world. Do watch ESOCast 165 to hear what previous ESO fellows have to say about the fellowship programme or watch the virtual tour to ESO’s premises from 2020 or https://www.youtube.com/watch?v=dK4q_OLvZ7Q where young scientists could ask questions about the fellowship programme.

Located in one of the most active research centres in Europe, the three-year long Garching fellowship offers plenty of opportunities to start new collaborations. Fellows are expected to engage in functional work for up to 25% of their time, equipping them with essential professional skills in diverse areas.

Fellows in Chile, on the other hand, interact with visiting astronomers from all areas of research and can easily collaborate with the Chilean astronomical community or with astronomers at other international observatories in the country. ESO Fellows in Chile contribute to ALMA or VLT duties up to a level of 80 nights per year during the first three years, while the fourth year is dedicated exclusively to scientific research.

Candidates are asked to apply online through the ESO Recruitment Portal. The application must be done using the ESO Application Form. Separate application forms must be completed for Garching and Santiago fellowships. The closing date for the 2026 fellowships is 15 October 2026.

1st announcement: ALMA at 15 years conference open for abstract submissions

1st announcement: ALMA at 15 years conference

Rationale
We are pleased to announce that the international conference "ALMA at 15 Years: Science, Synergies, and the Road Ahead" will be held in person from Feb. 22–26, 2027, at Academia Sinica’s Nangang campus in Taipei, Taiwan. The conference will highlight ALMA’s latest results, especially since the last Pan-ALMA conference held in 2023 and identify exciting directions for future ALMA research.

The program will feature invited and contributed science presentations, along with updates on the Wideband Sensitivity Upgrade (WSU), tutorial sessions on the archival and CARTA systems, and discussions of future ALMA prospects. Talks and posters presenting scientific work using ALMA and/or its synergies with other facilities across all areas of astronomy are welcome. Please visit the official conference website: https://2027alma.org

Important Dates
Abstract Submission Opens: June 15, 2026
Abstract Submission Deadline: September 15, 2026
Early-Bird Online-registration Opens: September 30, 2026
Notification of Abstract Acceptance: Late Oct./Early Nov., 2026
Early Bird Online-registration Deadline: November 27, 2026
Online Registration Deadline: January 20, 2027

SOC
John Carpenter (JAO, Chile), Paola Caselli (MPE, Germany), Marilyn Cruces (UC Chile, Chile), Leen Decin (KU Leuven, Belgium), Maria Diaz Trigo (ESO, Germany), Bunyo Hatsukade (NAOJ, Japan), Rodrigo Herrera-Camus (Universidad de Concepción, Chile), Jongsoo Kim (KASI, Korea), Lihwai Lin (ASIAA, Taiwan; Chair), Leslie Looney (UIUC, USA), Brett McGuire (MIT, USA), Jennifer Donovan Meyer (NRAO/NAASC, USA)

LOC
Cindy Chiu (ASIAA), Tien-Hao Hsieh (TARA), Sheng-Jun Lin (ASIAA), Yu-Nung Su (ASIAA), Ya-Wen Tang (ASIAA), Wei-Hao Wang (ASIAA; Chair)

Contact
Should you have any further inquiries, please feel free to contact the ALMA 2027 Abstract Submission & Registration Office (email: reg@2027alma.org)

We look forward to seeing you in Taipei!

Best regards,
Lihwai Lin (on behalf of SOC)

2nd Announcement: IR2026 registration open

IR 2026
Showcasing Science and Synergies in Thermal Infrared Astronomy
November 30 to December 4, 2026

Rationale:
Thermal infrared astronomy is entering a pivotal decade, driven by cutting-edge instrumentation and a growing range of science applications. At ESO, facilities such as MATISSE and VISIR and the newly operational ERIS provide high spatial and spectral resolution that enables detailed studies of protoplanetary disks, exoplanet atmospheres, evolved stars, and obscured galactic nuclei. In parallel, JWST/MIRI is delivering transformative science with unmatched sensitivity from space, highlighting the power of infrared observations.

Looking to the future, TAO is bringing ground-based IR observations to literal new heights at El Chajnantor with instruments like MIMIZUKU, VLTI/NOTT will allow new views of exoplanets thanks to mid-IR nulling and ELT/METIS will be pushing to new sensitivities in upcoming years. In space, potential projects like LIFE and PRIMA promise to continue expanding our view of the obscured universe.

The IR2026 conference will look to the both the past and the future, looking at the legacy of the soon to be decommissioned VISIR, what we have learnt so far from MIRI and MATISSE, and to prepare for the new instruments on the horizon.

Main Topics:

Instrument legacy and future visions: celebrating VISIR and preparing for the next decade
Multiwavelength synergy: how can ALMA, optical and X-ray observations work together with the thermal IR
New findings from current thermal IR instrumentation from the space and ground
Future thermal IR instrumentation: what we can learn from the next generation
Star and planet formation: disks, YSOs and embedded sources
Dust production and stellar evolution: AGB stars, Wolf-Rayets, SNe and transients
Galaxies and AGN: obscured star formation and accretion
Exoplanets in the thermal IR
Interstellar objects and solar system bodies in the thermal IR

Join us to discuss how further synergies between all these instruments can help us to further our understanding of our Universe in the IR!

Registration is open at: https://www.eso.org/sci/meetings/2026/IR_2026/registration/registration-open.html

Website: https://www.eso.org/sci/meetings/2026/IR_2026.html
Email: ir2026@eso.org