The PLAnetary Transits and Oscillations of stars (PLATO) mission is expected to launch in January 2027. A total of 8% of its data rate will be dedicated to complementary science targets selected from approved Guest Observer proposals. We seek to provide an open-source catalogue of variable stars in PLATO's first long-term observing field, LOPS2. We want to use existing observations from the Transiting Exoplanet Survey Satellite (TESS), which has observed many stars in LOPS2. We classified 38 million calibrated aperture light curves from the TESS-Gaia Light Curve pipeline (TGLC, G≲17) for 6 million unique sources in LOPS2 with two machine learning frameworks – a deep neural network and a feature-based gradient-boosted decision-tree ensemble. We combined their predictions to create this first version of the LOPS2 variability catalogue, performed manual vetting of a sub-sample classified light curves, and a statistical analysis of the results to validate our methodology and to assess the variability properties and parameters of the stars in the catalogue. Our classification resulted in the identification of approximately 72

In order to meet the science goals of the PLATO space mission, an extensive science calibration and validation plan has been designed. This paper describes this plan, as well as the methodology adopted to select the science calibration and validation stars that have entered its input catalogue. This is the so-called scvPIC, which is part of the general PLATO Input Catalogue (PIC) for the first selected long pointing field in the Southern Hemisphere known as LOPS2. While many of PLATO's science requirements needed dedicated stars as calibrators as discussed here, its most stringent requirement is the delivery of the age of the host stars of exoplanetary systems with an accuracy better than 10% for a G0V star of V = 10 mag, i.e. a nearby Sun-like star. This is presently not within reach for large populations of dwarfs and subgiants in the Milky Way as it requires the models of their stellar interiors to be improved. We discuss how this ambitious age requirement led to the selection of tens of thousands of red giants, and of thousands of main-sequence early F-type gravity-mode pulsators in order to deduce their internal rotation profile across stellar evolution. This asteroseismic observable will then be imported as key information into improved models of dwarfs and subgiants in the Milky Way as optimal modelling tools for ever better age-dating of the exoplanet hosts as the PLATO mission moves along. Additional calibrators and validators included in the scvPIC are a few thousands of binaries, a few hundreds of legacy and benchmark stars, a few hundred photometrically stable stars, and six transiting brown dwarfs.

Large spectroscopic surveys require robust pipelines capable of inferring stellar parameters over a wide range of the Hertzsprung-Russell (HR) diagram from data of varying quality. SDSS-V is one such survey, where the data from the lower-resolution, optical BOSS spectrograph will provide a large dataset covering a wide range of Galactic stellar populations. To better analyze these data, we present BOSS-CLAM, a generative, forward modeling pipeline for inferring effective temperature ($T_\mathrm{eff}$), surface gravity ($\log g$), metallicity ($[\mathrm{Fe/H}]$), and $α-$abundance ($[α/\mathrm{M}]$) from continuum-normalized BOSS spectra. BOSS-CLAM maps stellar labels to Non-negative Matrix Factorization (NMF) basis vector weights via a polynomial mapping jointly optimized with the spectral decomposition, which provides a more flexible framework for working with the lower-resolution BOSS data. Additionally, training labels are drawn from four complementary sources (ASPCAP, BOSS-MINESweeper, wide binaries, and a hot star validation sample), which enables coverage from cool M dwarfs through hot OB stars, and across a wide range of metallicity. We infer parameters for 1,708,214 BOSS spectra, with a recommended clean catalog of 915,514 sources. Validation against open and globular clusters demonstrates homogeneous, accurate abundances across a wide range of metallicity. Wide binary tests yield abundance uncertainties of $σ_{[\mathrm{Fe/H}]} \approx 0.15$ dex and $σ_{[α/\mathrm{M}]} \approx 0.06$ dex at SNR = 10. Finally, we demonstrate that the BOSS-CLAM catalog recovers known chemical structure of the Milky Way disk and is well-suited for Galactic archaeology, chemical tagging, and stellar population modeling. The pipeline, trained model, and catalog are publicly released as part of SDSS-V DR20.

The Sloan Digital Sky Survey-V (SDSS-V) Magellanic Genesis survey is a spectroscopic program designed to map the kinematic and chemical structure of the Magellanic Clouds using APOGEE and BOSS spectroscopy. This overview describes the survey's design, target selection, and science goals, and highlights some first results using these data. In the inner regions of the Large and Small Magellanic Clouds (LMC and SMC), the survey obtained high-resolution near-infrared APOGEE spectra (S/N 45) of 14,000 bright, oxygen-rich asymptotic giant branch (AGB-O) stars. These data provide contiguous spatial coverage of the Clouds' main bodies, enabling detailed chemo-dynamical studies. To explore extended structures, the survey includes BOSS optical spectroscopy of fainter red giant (RG) stars selected with DR3 data, reaching G 17.5. Many of these targets extend to the outer regions of the Clouds, which are known to span 20 deg (LMC) and 12 deg(SMC) and contain diffuse substructures of unclear origin. BOSS data in the inner regions also complement APOGEE by providing elements inaccessible in the near-infrared and enabling cross-calibration between instruments. The survey further includes APOGEE and BOSS observations of 300 evolved massive stars and a small sample of symbiotic binaries previously observed by APOGEE-1 and -2, enhancing our understanding of massive stellar evolution and complementing the SDSS-V main-sequence massive star program.

Binary interaction in massive stars is expected to produce a large population of intermediate-mass (2-8 M_⊙) envelope-stripped stars, yet such objects have remained elusive in the Milky Way. We report the identification of an unambiguous Galactic example in a short-period (P=5.94 d), double-lined spectroscopic binary, discovered in the SDSS-V Milky Way Mapper survey. The system consists of a rapidly rotating O-type star and a hotter, lower-mass companion, which shows He II and N IV emission lines with large radial velocity variations, revealing its binary nature. Combined orbital constraints and joint spectroscopic and photometric modelling show that the companion is a hot (T_∗≈ 60 kK), helium-rich star with a mass of 3.2-5.8 M_⊙, placing it squarely in the intermediate-mass regime and below values typically inferred for classical Wolf-Rayet (WR) stars. The system's short period, negligible eccentricity, and rapidly rotating O-star point to a post-interaction configuration following efficient mass transfer and spin-up of the accretor. Comparison with binary evolution models suggests that the stripped star is observed in a brief inflated phase following mass transfer, which increases its optical flux contribution and facilitates its detection. The inferred mass-loss rate logṀ = -6.3 ± 0.1 is in line with mass-loss rates observed for classical WR stars in the Milky Way and exceeds those measured for intermediate-mass stripped stars in the Magellanic Clouds, with the caveat that our target selection is biased towards systems with stronger emission features. As an unambiguous and well-characterised intermediate-mass stripped star, this system provides a key benchmark for models of binary evolution at solar metallicity, stripped-envelope supernova progenitors, and the formation of compact-object binaries.

Photometric missions such as Kepler and TESS have generated millions of light curves covering almost the entire sky, offering unprecedented opportunities to study stellar variability and advance our understanding of the Universe. In this data-rich environment, machine learning has emerged as a powerful tool to efficiently and accurately process and classify light curves according to their type of stellar variability. In this work, we introduce ASTRAFier: a novel Transformer-based model for variability classification that integrates Bidirectional Long Short-Term Memory (BiLSTM) and Convolutional Neural Networks (CNNs). The model operates directly on time series without requiring feature engineering, creating an easy-to-maintain and efficient end-to-end classification framework. We train and validate our model using both Kepler and TESS light curves and, respectively, achieve a classification accuracy of 94.26% on Kepler and 88.22% on TESS. We demonstrate scalability by deploying our model on ∼ 2.8 million TESS light curves from sectors 14, 15, and 26 (Kepler Field-of-View) delivered by MIT's Quick-look Pipeline (QLP) and release the resulting stellar variability catalog.

Mapping the local and distant Universe is key to our understanding of it. For decades, the Sloan Digital Sky Survey (SDSS) has made a concerted effort to map millions of celestial objects to constrain the physical processes that govern our Universe. The most recent and fifth generation of SDSS (SDSS-V) is organized into three scientific "mappers": the Milky Way Mapper, which aims to chart the various components of the Milky Way and constrain its formation and assembly; the Black Hole Mapper, which focuses on understanding supermassive black holes in distant galaxies across the Universe; and the Local Volume Mapper, which uses integral field spectroscopy to map the ionized interstellar medium in the Local Group. This paper describes the scope and content for the nineteenth data release (DR19) of SDSS, which is the most substantial to date in SDSS-V. DR19 is the first to contain data from all three mappers. Additionally, we also describe nine value-added catalogs that enhance the science that can be conducted with the SDSS-V data. Finally, we discuss how to access SDSS DR19 and provide illustrative examples and tutorials.

The Sloan Digital Sky Survey V (SDSS-V) is pioneering panoptic spectroscopy: it is the first all-sky, multiepoch, optical-to-infrared spectroscopic survey. SDSS-V is mapping the sky with multiobject spectroscopy (MOS) at telescopes in both hemispheres (the 2.5 m Sloan Foundation Telescope at Apache Point Observatory and the 100-inch du Pont Telescope at Las Campanas Observatory), where 500 zonal robotic fiber positioners feed light from a wide-field focal plane to an optical (R similar to 2000, 500 fibers) and a near-infrared (R similar to 22,000, 300 fibers) spectrograph. In addition to these MOS capabilities, the survey is pioneering ultra-wide-field (similar to 4000 deg(2)) integral field spectroscopy enabled by a new dedicated facility (LVM-I) at Las Campanas Observatory, where an integral field spectrograph (IFS) with 1801 lenslet-coupled fibers arranged in a 0 degrees.5-diameter hexagon feeds multiple R similar to 4000 optical spectrographs that cover 3600-9800 angstrom. SDSS-V's hardware and multiyear survey strategy are designed to decode the chemodynamical history of the Milky Way and tackle fundamental open issues in stellar physics in its Milky Way Mapper program, trace the growth physics of supermassive black holes in its Black Hole Mapper program, and understand the self-regulation mechanisms and the chemical enrichment of galactic ecosystems at the energy injection scale in its Local Volume Mapper program. The survey is well timed to multiply the scientific output from major all-sky space missions. The SDSS-V MOS programs began robotic operations in 2021; IFS observations began in 2023 with the completion of the LVM-I facility. SDSS-V builds on decades of heritage of SDSS's pioneering advances in data analysis, collaboration spirit, infrastructure, and product deliverables in astronomy.

Context. KIC 4150611 is a high-order (seventh-order) multiple composed of a triple system with: a F1V primary (Aa), which is eclipsed on a 94.2 d period by a tight binary composed of two K/M dwarfs (Ab1 and Ab2) that also eclipse each other; an eccentric, eclipsing binary composed of two G stars (Ba and Bb); and another faint eclipsing binary composed of two stars of unknown spectral type (Ca and Cb). In addition to its many eclipses, the system is an triple-lined spectroscopic multiple (Aa, Ba, and Bb) and the primary (Aa) is a hybrid pulsator that exhibits high amplitude pressure and gravity modes (g-modes). Furthermore, its g-modes are arrayed in a period-spacing pattern, which greatly assists with mode identification and asteroseismic modelling. In aggregate, this richness in physics offers an excellent opportunity to obtain a precise physical characterisation for some of the stars in this system. Aims. In this work we estimate the stellar parameters of the primary (Aa) by performing asteroseismic analysis on its period-spacing pattern. Methods. We used the C-3PO neural network to perform asteroseismic modelling of the g-mode period-spacing pattern of Aa, examining the interplay of this information with external constraints from spectroscopy (T-eff and log(g)) and eclipse modelling (R). To estimate the level of uncertainty due to different frequency extraction and pattern identification processes, we considered four different variations of the period-spacing patterns. To better understand the correlations between and the uncertainty structure of our parameter estimates, we also employed a classical, parameter-based Markov chain Monte Carlo (MCMC) grid search on four different stellar grids. Results. The externally constrained model that best fits the period-spacing pattern arrives at estimates of the stellar properties for Aa of M = 1.51 +/- 0.05 M-circle dot, X-c = 0.43 +/- 0.04, R = 1.66 +/- 0.1 R-circle dot, f(ov) = 0.010, Omega(c) = 1.58 +/- 0.01 d(-1) with rigid rotation to within the measurement errors, log(T-eff) = 3.856 +/- 0.008 dex, log(g) = 4.18 +/- 0.04 dex, and log(L) = 0.809 +/- 0.005 dex, which agree well with previous measurements from eclipse modelling, spectroscopy, and the Gaia DR3 luminosity. Conclusions. We find that the near-core properties of the best-fitting asteroseismic models are consistent with external constraints from eclipse modelling and spectroscopy. For stellar properties not related to the near-core region, external constraints on the asteroseismic best-fitting models are informative. Aa appears to be a typical example of a gamma Dor star, fitting well within existing populations. We find that Aa is quasi-rigidly rotating to within the uncertainties, and note that the asteroseismic age estimate for Aa (1100 +/- 100 Myr) is considerably older than the young age (35 Myr) implied by previous isochrone fits to the B binary in the literature. Our MCMC parameter-based grid search agrees well with our pattern-modelling approach. Improved future modelling could come from detailed coverage of metallicity effects and a careful treatment of envelope physics.

Context. The mass discrepancy problem, observed in high-mass stars within eclipsing binaries, highlights systematic differences between dynamical and evolutionary mass estimates, challenging the accuracy of stellar evolution models. Aims. We aim to determine whether analysis methods directly contribute to this discrepancy and to assess how methodological improvements might reduce or clarify it. Methods. To address this, we developed a new self-contained framework that simultaneously models the photometric and spectroscopic data, minimising biases introduced by traditional iterative approaches and enabling consistent parameter optimisation. Results. We present this framework alongside validation tests on synthetic data and demonstrate its application to three well-studied observed binaries, including one system known for its pronounced mass discrepancy. The framework recovers multiple viable solutions from distinct local minima, including one that reduces the mass discrepancy. Conclusions. These results illustrate how methodological biases, rather than evolutionary model assumptions, can contribute to the mass discrepancy problem. We further highlight that external constraints, such as independent distance estimates or evolutionary models, may be necessary to distinguish between degenerate solutions. Expanding this analysis to a larger sample will provide a more complete understanding, with forthcoming results in the next paper in this series.

In this work, we seek to characterise a large sample of 14377 main sequence eclipsing binaries in terms of their stellar, asteroseismic, and orbital properties. We conduct manual vetting on a 4000-target subset of our full 14377-target sample to identify targets with pressure or gravity modes. We infer stellar properties including the mass, convective core mass, radius, and central H fraction for the primary using Gaia Data Release 3 effective temperature and luminosity estimates and a grid of asteroseismically calibrated stellar models. We use surface brightness ratio and radius ratio estimates from previous eclipse analysis to study the effect of binarity on our results. Our manual vetting identifies 751 candidate g-mode pulsators, 131 p-mode pulsators, and a further 48 hybrid pulsators. The inferred stellar properties of the hybrid and p-mode pulsators are highly correlated, while the orbital properties of the hybrid pulsators align best with the g-mode pulsators. The g-mode pulsators themselves show a distribution that peaks around the classical g dor instability region but extends continuously towards higher masses, with no detectable divide between the classical g dor and SPB instability regions. There is evidence at the population level for a heightened level of tidal efficiency in stars showing g-mode or hybrid variability. Correcting the primary mass inference for binarity based on eclipse measurements of the surface brightness and radius ratios results in a relatively small shift towards lower masses. This work provides a working initial characterisation of this sample from which more detailed analyses folding in asteroseismic information can be built. It also provides a foundational understanding of the limitations and capabilities of this kind of rapid, scalable analysis that will be highly relevant in planning the exploitation of future large-scale binary surveys.

Context. KIC 4150611 is a high-order (seventh-order) multiple composed of a triple system with: a F1V primary (Aa), which is eclipsed on a 94.2 d period by a tight binary composed of two K/M dwarfs (Ab1 and Ab2) that also eclipse each other; an eccentric, eclipsing binary composed of two G stars (Ba and Bb); and another faint eclipsing binary composed of two stars of unknown spectral type (Ca and Cb). In addition to its many eclipses, the system is an triple-lined spectroscopic multiple (Aa, Ba, and Bb) and the primary (Aa) is a hybrid pulsator that exhibits high amplitude pressure and gravity modes (g-modes). Furthermore, its g-modes are arrayed in a period-spacing pattern, which greatly assists with mode identification and asteroseismic modelling. In aggregate, this richness in physics offers an excellent opportunity to obtain a precise physical characterisation for some of the stars in this system. Aims. In this work we estimate the stellar parameters of the primary (Aa) by performing asteroseismic analysis on its period-spacing pattern. Methods. We used the C-3PO neural network to perform asteroseismic modelling of the g-mode period-spacing pattern of Aa, examining the interplay of this information with external constraints from spectroscopy (Teff and log(g)) and eclipse modelling (R). To estimate the level of uncertainty due to different frequency extraction and pattern identification processes, we considered four different variations of the period-spacing patterns. To better understand the correlations between and the uncertainty structure of our parameter estimates, we also employed a classical, parameter-based Markov chain Monte Carlo (MCMC) grid search on four different stellar grids. Results. The externally constrained model that best fits the period-spacing pattern arrives at estimates of the stellar properties for Aa of M = 1.51 ± 0.05 M⊙, Xc = 0.43 ± 0.04, R = 1.66 ± 0.1 R⊙, fov = 0.010, Ωc = 1.58 ± 0.01 d−1 with rigid rotation to within the measurement errors, log(Teff) = 3.856 ± 0.008 dex, log(g) = 4.18 ± 0.04 dex, and log(L) = 0.809 ± 0.005 dex, which agree well with previous measurements from eclipse modelling, spectroscopy, and the Gaia DR3 luminosity. Conclusions. We find that the near-core properties of the best-fitting asteroseismic models are consistent with external constraints from eclipse modelling and spectroscopy. For stellar properties not related to the near-core region, external constraints on the asteroseismic best-fitting models are informative. Aa appears to be a typical example of a γ Dor star, fitting well within existing populations. We find that Aa is quasi-rigidly rotating to within the uncertainties, and note that the asteroseismic age estimate for Aa (1100 ± 100 Myr) is considerably older than the young age (35 Myr) implied by previous isochrone fits to the B binary in the literature. Our MCMC parameter-based grid search agrees well with our pattern-modelling approach. Improved future modelling could come from detailed coverage of metallicity effects and a careful treatment of envelope physics.

Space-based photometry has substantially increased the number of pulsating stars found in binary systems by more than four orders of magnitude. Combined with high-resolution spectroscopy, high-precision photometry offers model-independent constraints on stellar parameters and internal processes. The advent of space-based photometric surveys has given us access to populations of tidally perturbed pulsators, which offer a unique and demanding set of constraints on tidal physics and stellar interiors. However, we lack the ability to undertake multi-epoch, high-resolution spectroscopy at large scale. The ability to obtain phase-resolved, high-resolution spectra would allow us to place precise, model-independent constraints on the stellar properties of pulsators in binary systems that will truly test our close binary asteroseismic modelling techniques, leading to much-needed constraints on fundamental stellar and binary physics. The need to properly cover the large parameter-space of binary stars demands a large-scale, population-level analysis in order to understand the complex landscape of binary stellar evolution. To enable this population-level analysis, we need a dedicated multi-fibre spectrograph (30–200 fibres) with high spectral resolution (R≥ 50000), high signal-to-noise ratio (S/N≥ 300), and a limiting magnitude of approximately 15. Such a spectrograph would be capable of efficiently resolving the pulsation variability on the order of minutes and orbit motion on the order of days to years for many targets.

Context. Observations of double-lined spectroscopic eclipsing binaries are ideal for studies of stellar evolution. Such stars have tight model-independent constraints on their masses and radii. When used in combination with spectroscopically determined effective temperatures and surface abundances, they can be used to calibrate and improve stellar evolution models. Aims. The main goal of this work is to determine whether the observed trends of surface nitrogen abundance in single and binary stars can be explained by wave-induced mixing occurring in the stellar envelope. Methods. We used the MESA stellar evolution code to run simulations of single B-type stars with envelope mixing induced by internal gravity waves. We compared the outcome of these models to observations of the surface nitrogen abundance for samples of detached eclipsing binary systems and of single B-type stars. From this comparison, we were able to determine the amount of wave-induced mixing required to bring the model predictions in agreement with the observations.Results. We find nitrogen to be enriched at the surface of theoretical models with wave-induced mixing provided that we use levels above log(Denv/cm(2) s(-1)) = 5-6 at the position of the convective core boundary. This corresponds to the highest levels of envelope mixing derived from asteroseismic modelling of single B stars. A prominent observation is that the B-type components of detached eclipsing binaries do not show any nitrogen surface enhancement, which can be explained by their relatively fast rotation enforced by the tidal forces in the systems. The slowly rotating or evolved stars among the sample of single B stars do reveal a nitrogen enhancement. Our findings on the difference in surface nitrogen abundances between single B stars and B-type components of detached binary systems could potentially be explained by internal wave-induced mixing profiles based on recent two-dimensional hydrodynamical simulations of rotating B stars with waves excited at the interface between the convective core and radiative envelope. Such wave-induced mixing decreases with increasing rotation and might act in combination with additional rotational mixing. Conclusions. Our findings motivate future asteroseismic studies in large samples of single B stars and pulsating eclipsing binaries with B-type components as optimal laboratories to further test our interpretations in terms of internal wave mixing.

We report new spectroscopic and interferometric observations of the Pleiades binary star Atlas, which played an important role nearly 3 decades ago in settling the debate over the distance to the cluster from ground-based and space-based determinations. We use the new measurements, together with other published and archival astrometric observations, to improve the determination of the 291 day orbit and the distance to Atlas (136.2 ± 1.4 pc). We also derive the main properties of the components, including their absolute masses (5.04 ± 0.17 M _⊙ and 3.64 ± 0.12 M _⊙ ), sizes, effective temperatures, projected rotational velocities, and chemical compositions. We find that the more evolved primary star is rotationally distorted, and we are able to estimate its oblateness and the approximate orientation of its spin axis from the interferometric observations. The spin axis may well be aligned with the orbital axis. Models of stellar evolution from the Modules for Experiments in Stellar Astrophysics (or MESA) that account for rotation provide a good match to all of the primary’s global properties, and point to an initial angular rotation rate on the zero-age main sequence of about 55% of the breakup velocity. The current location of the star in the Hertzsprung–Russell diagram is near the very end of the hydrogen-burning main sequence, at an age of about 105 Myr, according to these models. Our spectroscopic analysis of the more slowly rotating secondary indicates that it is a helium-weak star, with other chemical anomalies.

Context. In the modern era of large-scale photometric time-domain surveys, relatively rare but information-rich eclipsing binary systems can be leveraged at a population level across the Hertzsprung-Russel diagram to improve our knowledge of stellar evolution. This high-precision photometry is also excellent for assessing and exploiting the asteroseismic properties of such stars and results in a powerful synergy that has great potential for shedding light on how stellar interiors and tides affect stellar evolution and mass transfer. Aims. In this work, we seek to characterise a large sample of 14 377 main sequence eclipsing binaries in terms of their stellar, astero-seismic, and orbital properties. Methods. We conducted manual vetting on a sub-set of 4000 targets from our full 14 377 target sample to identify targets with pressure or gravity modes. We inferred stellar properties including mass, the convective core mass, radius, and central H fraction for the primary using the Gaia Data Release 3 effective temperature and luminosity estimates and a grid of asteroseismically calibrated stellar models. We used surface brightness ratio and radius ratio estimates from previous eclipse analyses to study the effect of binarity on our results. Results. Through our manual vetting, we identified 751 candidate g-mode pulsators, 131 p-mode pulsators, and a further 48 hybrid pulsators. The inferred stellar properties of the hybrid and p-mode pulsators are highly correlated, while the orbital properties of the hybrid pulsators align best with the g-mode pulsators. The g-mode pulsators themselves show a distribution that peaks around the classical γ Dor instability region but extends continuously towards higher masses, with no detectable divide between the classical γ Dor and SPB instability regions. There is evidence at the population level for a heightened level of tidal efficiency in stars showing g-mode or hybrid variability. We corrected the primary mass inference for binarity based on eclipse measurements of the surface brightness and radius ratios, resulting in a relatively small shift towards lower masses. Conclusions. This work provides a working initial characterisation of this sample from which more detailed analyses folding in aster-oseismic information can be built. It also provides a foundational understanding of the limitations and capabilities of this kind of rapid, scalable analysis that will be highly relevant in planning the exploitation of future large-scale binary surveys.

Context. The Transiting Exoplanet Survey Satellite (TESS) mission has observed hundreds of millions of stars, substantially contributing to the available pool of high-precision photometric space data. Among them are the relatively rare gamma Doradus/delta Scuti (gamma Dor/delta Sct) hybrid pulsators, which have been previously studied using Kepler data. These stars are perfect laboratories to probe both inner and outer interior stellar layers thanks to them exhibiting both pressure and gravity modes. Aims. We seek to classify an all-sky sample of AF stars observed by TESS to find previously undiscovered hybrid pulsators and supply them in a catalogue of candidates. We also aim to compare the light curves produced with the TESS-Gaia Light Curve (TGLC) pipeline, currently underused in variability studies, with other publicly available light curves. Methods. We compared dominant and secondary frequencies of confirmed hybrid pulsators in Kepler, extended mission Quick Look Pipeline (QLP) data, and nominal and extended mission TGLC data. We then used a feature-based positive unlabelled (PU) learning classifier to search for new hybrid pulsators amongst TESS AF stars and investigated the properties of the detected populations. Results. We find that the variability of confirmed hybrids in TGLC agrees well with the one occurring in QLP light curves and has a high recovery rate of Kepler-extracted frequencies. Our 'smart binning' method allows for robust extraction of hybrids from large unlabelled datasets, with an average out-of-bag prediction for test set hybrids at 93.04%. The analysis of dominant frequencies in high-probability candidates shows that we find more pressure-mode dominant hybrids. Our catalogue includes 62 026 new candidate light curves from the nominal and extended TESS missions, with individual probabilities of being a hybrid in each available sector. Conclusions. Our catalogue results in a major increase of TESS gamma Dor/delta Sct hybrid pulsators, suitable for further asteroseismic studies.

The goal of this paper is to describe the science verification of Milky Way Mapper (MWM) APOGEE Stellar Parameter and Chemical Abundances Pipeline (ASPCAP) data products published in Data Release 19 (DR19) of the fifth phase of the Sloan Digital Sky Survey (SDSS-V). We compare MWM ASPCAP atmospheric parameters T _eff , log g , 24 abundances of 21 elements (carbon, nitrogen, and oxygen have multiple sources for deriving their abundance values) and their uncertainties determined from Apache Point Observatory Galactic Evolution Experiment (APOGEE) spectrograph spectra with those of the literature and evaluate their accuracy and precision. We also test the zero-point calibration of the v _rad derived by the APOGEE Data Reduction Pipeline. This data release contains ASPCAP parameters for 964,989 stars, including all APOGEE-2 targets expanded with new observations of 336,511 stars from the Apache Point Observatory observed until 2023 July 4. Overall, the new T _eff values show excellent agreement with the IRFM scale, while the surface gravities exhibit slight systematic offsets compared to asteroseisimic gravities. The estimated precision of T _eff is between 50 and 70 K for giants and 70–100 K for dwarfs, while surface gravities are measured with a precision of 0.07–0.09 dex for giants. We achieve an estimated precision of 0.02–0.04 dex for multiple elements, including metallicity, α , Mg, and Si, while the precision of at least 10 elements is better than 0.1 dex.

The European Space Agency has selected PLATO (PLAnetary Transits and Oscillations of stars) for its M3 launch which is scheduled for 2026. With its extremely large field of view, PLATO is designed to obtain photometric measurements over an extended period for bright stars in order to detect and characterise (primarily) rocky planets in the habitable zones of solar type stars. The PLATO measurements will have sufficient sensitivity to determine the mass, radius and age of the host stars with unprecedented accuracy. The PLATO planet database will provide the first large-scale catalogue of accurately and homogeneously characterised small planets at intermediate orbital periods, which will can be used to severely constraint planet formation theories. This would facilitate large scale comparative exo-planetology. In addition the bright PLATO host stars will be ideal targets for atmospheric study with next generation facilities such as the ELT. The PLATO sensitivity will be sufficient to detect pulsations from stars across the HR diagram allowing a deep understanding of stellar structure and evolution to be developed using parameters determined from asteroseismology.