DustPedia and Local Volume Legacy (LVL) are two samples representative of the local galaxy population, including in total ∼1000 unique objects of all morphological types, with a wide range of stellar masses and star formation activity, and a spectral coverage from the ultraviolet to the far-infrared. The purpose of this work is to show that these samples cover two complementary ranges in stellar mass and galaxy morphology, making them an ideal set for constraining the dominant processes in the evolution of the galactic dust content. Using the multi-wavelength data provided by the two surveys, we fitted the galaxies' spectral energy distribution and estimated their physical properties, in particular the stellar mass, M_*, the specific dust mass, sM_ =M_ /M_*, and the specific star formation rate, sSFR = SFR$/M_*$. dust dust By combining DustPedia and LVL, we highlight that the trend of log_ 10 (sM_ dust ) with log_ 10 (M_*) is not monotonic. Thanks to a large number of objects across a wide range of M_*, we have been able to fit two smoothly joined linear correlations: a positive one for log_ 10 (M_ * /M_⊙)łesssim 9.5 (a range populated mostly by LVL late spirals and irregulars), and a negative one for larger-mass, mainly DustPedia, spirals (with early-type galaxies being distinct and more dispersed in the same mass regime). For log_ 10 (M_ * /M_⊙)> 9.5, we confirm a strong correlation between sM_̊m dust and sSFR; dwarf galaxies, instead, lie below this trend, showing a large scatter of sM_̊m dust for -10.5< -1 ) <-9.0. By using chemical evolution models we find that the observed log_ 10 (sM_ dust )--log_ 10 (M_ * ) and log_ 10 (sM_ dust )-- trends can be interpreted mainly by variations in the initial gas mass budget and the galaxy ages, respectively. Low-mass Sm-Irr galaxies with low sM_ dust and a high sSFR can only be reproduced by the models by assuming a highly efficient photofragmentation rate of large grains, and/or low grain growth in clouds.

The narrow-line Seyfert 1 galaxy IRAS 17020+4544 is one of the few known sources to exhibit a multiphase outflow in the highly ionized and molecular phases consistent with active galactic nucleus (AGN) feedback operating in the ``energy-conserving'' regime. We aim to characterize the properties of the ionized warm ionized gas in IRAS 17020+4544 using new optical integral-field spectroscopic (IFS) data, and to assess the presence of outflowing ionized gas and its connection with the other gas phases and its role in the AGN feedback. We analyzed new optical seeing-limited IFS observations obtained with MEGARA at the Gran Telescopio Canarias in both low- (R∼6000; LR) and medium-resolution (R∼12000; MR) modes. We modeled the Hα and OIII łambda5007 emission lines using multi-Gaussian fitting to characterize in detail the ionized gas kinematics, particularly that of the ionized outflow, in order to derive its energetics and compare it with those of the X-ray and molecular phases. Diagnostic diagrams (WHAN, WHaD, and BPT) were used to investigate the dominant ionization mechanism. We identify a fast ionized outflow traced by both Hα and OIII emission lines, with similar extensions (R_ line. The fast outflow follows an energy-conserving regime in both Hα and the kpc and ∼0.5 kpc, respectively) and velocities (v_ $, respectively). A slower ionized outflow (v_ ) is also detected in the secondary component of the ∼ 1460 and 1240 km s -1 km s$^ -1 OIII OIII lines (from the LR setup), while the slower outflow follows a ``momentum-driven'' regime. The ionized outflows are enclosed within the molecular outflow detected with NOEMA (R_ kpc), and the large momentum boosts derived in both phases suggest efficient AGN feedback, likely dominated by radiatively driven winds (quasar-mode) rather than kinetic (jet-driven) processes. Ionization diagnostics indicate that the outflow is primarily AGN-driven, although a contribution from star-formation-driven excitation cannot be ruled out, and some contribution from shocks cannot be excluded on smaller scales. Our results support a scenario in which the multiphase outflow in IRAS17020+4544 is AGN-driven and energy-conserving in the different (i.e., highly ionized, warm ionized, and molecular) phases, efficiently coupling the AGN energy to the host galaxy's interstellar medium. The molecular outflow appears to be the dominant phase, while the ionized phase contributes less to the mass budget and feedback efficiency.

A recent study suggests that CM chondrite-like planetesimals formed in the vicinity of Saturn, in a pressure bump outside the gap carved by proto-Jupiter. While a fraction of these objects was implanted into the asteroid belt as a consequence of Saturn's growth, it remains unclear whether the scattered remainder could reach the ice giant region and mix with more distant carbonaceous reservoirs. We test whether outward scattering during Saturn’s growth and migration can implant CM-like bodies onto long-lived orbits in the Uranus-Neptune region, where they could contaminate the CI reservoir. We performed N-body integrations of 100-km planetesimals launched from the outer edge of Jupiter’s gap, including gas drag and the gravitational perturbations of growing Jupiter and Saturn, with optional inclusion of a nearby ice giant embryo. We explored a range of gas surface-density profiles and growth timescales. While Saturn’s growth efficiently scatters CM-like planetesimals, fewer than sim2% are implanted beyond 15 au, even under gas-rich conditions, because gas drag damps their eccentricities and drives them back toward their pericenters rather than allowing them to circularize at larger distances. Adding an ice giant core modestly increases the outward reach (up to $ %$ in the most gas-rich case), but Type-I migration further lowers perihelia, making long-term retention at large distances difficult. For a CM mass budget of M_ ̊m CM,tot this implies that at most M_ ̊m CM łesssim0.02–0.04,M_⊕ reaches 15-25,au, corresponding to a diluted mass fraction of łesssim(1–2) in the outer ring, and hence negligible contamination of the CI reservoir. Combined with the distinct radial distributions of CM- and CI-like asteroids in the belt, these results imply limited mixing of carbonaceous reservoirs and isolation of the CI reservoir. This strongly suggests that Uranus and Neptune formed later than Jupiter and Saturn, under lower gas densities, supporting a sequential giant-planet formation model.

Abstract FQ Cir was an ordinary fast He/N classical nova, peaking at V = 10.9. The pre-eruption and post-eruption counterpart was at V = 14.0, making this the smallest known classical nova amplitude, 3.1 mag. The nova light and the counterpart coincide at 0 <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mover> <mml:mrow> <mml:mo>.</mml:mo> </mml:mrow> <mml:mrow> <mml:mtext>″</mml:mtext> </mml:mrow> </mml:mover> </mml:math> 034, and the counterpart is a rare hot/blue emission-line star with flickering, so the identification of the quiescent nova is certain. The counterpart is a weak Be main-sequence star, B1 V(n)(e). A coherent photometric period appears in all four TESS Sectors and in the AAVSO post-eruption light curve, as ellipsoidal modulation with an orbital period of 2.041738 days. The companion must have been spun up to a fast rotation, and like all Be stars, a decretion disk is exuded. With the constraints of the blackbody radius and the main sequence, the companion mass is 13.0 <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msubsup> <mml:mrow/> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>0.5</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>+</mml:mo> <mml:mn>0.2</mml:mn> </mml:mrow> </mml:msubsup> </mml:math> M ⊙ , with radius 6.2 ± 0.2 R ⊙ . This is the discovery of a cataclysmic variable with a high-mass companion, a new class that we call “high-mass cataclysmic variables.” The white dwarf mass is 1.25 ± 0.10 M ⊙ and must have an accretion disk that supplies fuel for the nova eruption. FQ Cir represents a new mode of accretion in interacting binaries, with Roche lobe overflow from the decretion disk feeding mass into the usual accretion disk around the white dwarf, for disk-to-disk accretion. From the mass budget of the binary, the primary star must have its initial mass be &gt;7.7 M ⊙ , forming an ONe white dwarf, so FQ Cir can never become a Type Ia supernova.

ABSTRACT Understanding the optical properties of different sea ice types is crucial for improving knowledge of energy balance, heat and mass budgets, and for enhancing the accuracy of remote sensing retrievals. The in situ-based spectral characteristics of coastal first-year sea ice in eastern Liaodong Bay, Bohai Sea, were systematically analysed. A regional reflectance database was established in January 2025, collecting 49 ice samples with diverse types, thicknesses, densities, sampling locations, and observation angles. The results show that scale-like ice exhibited the highest visible-band reflectance (>0.7), followed by young ice with considerable variability, while frazil ice, nilas, and needle ice exhibited lower reflectance due to their thin structure, loose texture, and uneven surfaces, and sediment-laden ice had the lowest reflectance. Sea ice reflectance was strongly related to ice density, with lower-density ice showing higher values, and displayed a significant exponential relationship with ice thickness in both ultraviolet and visible bands (p < 0.01), with the ultraviolet band yielding higher coefficients of determination. The Hemispherical Directional Reflectance Factor (HDRF) increased with azimuth angle, reaching a minimum at nadir (0° zenith), and reflectance grew with zenith angle, with forward scattering being dominant, followed by side and back scattering. Additionally, comparisons between Geostationary Ocean Colour Imager II (GOCI-II) satellite data and in situ measurements showed similar spectral patterns, including primary peaks in the ultraviolet–blue bands and a secondary maximum near 600–700 nm, although GOCI-II reflectance was generally 10–20% lower. Moreover, preliminary results based on four machine learning algorithms indicate that GOCI-II satellite data have clear discriminatory potential for classifying sea ice by both region and thickness.

Plastic debris densities in Barcelona waters are comparable to those in subtropical gyres, with the Barcelona coastline being among the most affected by plastic pollution in the Mediterranean Sea. A mass budget for discharged plastic debris was estimated for the year 2020-2021. The calculation used discharge volume data from the combined sewer overflow system and surrounding rivers, combined with linear regressions derived from collected samples at these sites and representative weights for each plastic size class. Fluxes were determined from Lagrangian numerical simulations, which were informed by the amounts of discharged plastic debris during discharge events. To account for unresolved coastal processes, a probabilistic beaching module was applied to the Lagrangian numerical model. Beaching amounts reached 98.4% for discharges from the combined sewer overflow system, mostly affecting urban beaches. River discharges were more strongly influenced by hydrodynamic conditions, although there was substantial retention of particles in the Llobregat River mouth. A total of 6.0×1010 items year-1 of plastic debris were discharged, corresponding to a mass budget of 17.0 metric tonnes year-1. Such high levels of plastic debris discharges from the Barcelona coastline underscore the urgent need to reduce plastic waste at its source and implement mitigation measures before it reaches the marine environment.

Summary Geocenter motion, defined as the displacement of Earth’s center of mass relative to its center of figure, is crucial for maintaining the International Terrestrial Reference Frame origin and quantifying large-scale mass redistribution. However, whether observing geocenter motion by tracking satellite orbits or inferring it using geophysical models, accurately acquiring such subtle motions imposes stringent requirements on the consistency and precision of both tracking data and geophysical models. This study improves geocenter motion estimates derived from the combination of GRACE/GRACE-FO time-variable gravity (TVG) and Ocean Bottom Pressure (OBP) models (the GRACE-OBP method) in two ways. First, we apply a forward modelling technique to mitigate land–ocean leakage in GRACE/GRACE-FO TVG fields, which demonstrably outperforms empirical coastline buffer-zone corrections in controlled simulation experiments. Second, we introduce the Bayesian Three-Cornered Hat (BTCH) method to optimally combine geocenter series derived from multiple GRACE solutions and two independent OBP models (ECCO2 and MPIOM), producing an improved geocenter product without requiring a ground-truth reference. Uncertainty analysis shows that the noise level is governed primarily by the GRACE solution, and that BTCH provides a clearer advantage over equal-weighted averaging when the number of input series is limited, reducing the noise level by about 30 per cent. After restoring atmospheric and oceanic contributions, our improved geocenter series shows good agreement with the CSR SLR-derived geocenter product. Although uncertainty levels vary among individual solutions, the estimated annual and secular trend signals are broadly consistent and show limited sensitivity to the choice of GRACE TVG solution and OBP model. Using the improved geocenter series, we revisit the annual geocenter oscillation and its drivers; the results indicate that cryospheric mass variability and land-ocean mass exchange (i.e. sea-level fingerprints) provide non-negligible contributions to the annual geocenter cycle and improve consistency with observations. Finally, the improved geocenter series yields the lowest uncertainty in degree-1 mass variations, with a global RMS of 0.55 mm. Incorporating these degree-1 terms into mass budget assessments yields secular trends of 38.8 Gt/yr for the Antarctic Ice Sheet and 0.57 mm/yr for global mean ocean mass, highlighting the need for accurate geocenter corrections to support reliable long-term climate monitoring.

The dynamics of turbulent Rayleigh–Taylor (RT) mixing layers is investigated across a broad range of Atwood and Reynolds numbers using the statistically stationary RT flow configuration – a computational framework that enables simulation of a minimal flow unit for RT flows at reduced cost. Normalizations are developed for all dominant non-transport terms in the continuity, mixed mass and turbulent kinetic energy budgets in terms of the input parameters: the mixing layer height $h$ , gravitational acceleration $g$ and fluid densities $\rho _H$ and $\rho _L$ . Most normalized quantities collapse well across the parameter space. In some cases, variations in the Atwood number $A$ (or the density ratio $R$ ) lead to consistent integral magnitudes but spatially shifted profiles. These shifts are primarily related to a division by density and are similarly observed in the analytical solution of the one-dimensional variable-density diffusion problem. The analysis introduces a reference density for the mixed mass, examines trends in Favre-averaged statistics and derives a scaling law for the growth rate of the mixing layer. For height definitions encompassing the full extent of the layer, the conventional growth parameter, $\alpha =\dot {h}^2/4Agh$ , varies with Atwood number. Our analysis leads to an alternative formulation using an effective Atwood number, $A^*= (\ln R)/2$ , that is consistent with the scaling proposed by Belen’kii &amp; Fradkin (1965 Trudy FIAN 29, 207–238). Applying this $A^*$ scaling to existing RT data, the corresponding growth parameter, $\alpha ^*=\dot {h}^2/4A^*gh$ , remains nearly constant across all Atwood numbers considered, offering a unified scaling for variable-density RT flows.

Abstract. From 19 to 23 December 2018, an atmospheric river sourced in the Atlantic hit the French–Italian Concordia station, located at Dome C, East Antarctic Plateau, 3233 m above sea level (a.s.l.). It induced a significant surface warming (+18 °C in 3 d), combined with high specific humidity (3-fold increase in 3 d) and a strong isotopic anomaly in water vapour (+17 ‰ for δ18O). The isotopic composition of water vapour monitored during the event may be explained by the isotopic signature of long-range water transport, and by local moisture uptake during the event. In this study, we used continuous meteorological and isotopic water vapour observations, together with the atmospheric general circulation model LMDZ6iso, to describe this event and quantify the influence of each of these processes. The presence of mixed-phase clouds during the event induced a significant increase in downward long wave radiation, leading to high surface temperature and resulting in high turbulent mixing in the boundary layer. Although surface fluxes are underestimated in LMDZ6iso, near-surface temperature and specific humidity are well represented. The surface vapour δ18O is accurately simulated during the event, despite an overestimated amplitude in the diurnal cycle outside of the event. Using the LMDZ6iso simulation, we perform a surface water vapour mass budget by decomposing total specific humidity into contributions from individual processes. Our analysis demonstrates that surface sublimation, which becomes significantly stronger during the event compared to typical diurnal cycles, emerges as the dominant driver of the vapour δ18O signal at the peak of the event, accounting for approximately 70 % of the total contribution. The second largest contribution comes from moisture input via large-scale advection associated with the atmospheric river, accounting for approximately 30 % of the total. Consequently, our results reveal that the isotopic signal monitored in water vapour during this atmospheric river event reflects both long-range moisture advection and interactions between the boundary layer and the snowpack. Only specific meteorological conditions driven by a pronounced moisture intrusion can explain these strong interactions. Given the marked imprint of air–snow exchanges on the vapour isotopic signal, improving the representation of local processes in climate models could substantially improve the simulation of the isotopic signal over Antarctica and provide valuable insight into moisture uptake processes.

Abstract Recent discoveries of streamer-like structures around protostellar sources challenge the traditional picture of isolated, axisymmetric star formation. Here, we present new Atacama Large Millimeter/submillimeter Array observations of [BHB2007]-1, a flat-spectrum source connected to at least three such elongated structures. Two of these features are symmetrically located to the north and south of the disk, with velocities aligned with the disk on their respective sides. However, their unbound kinematics and curved morphology make it difficult to determine their origin. Possible explanations include outflows, interactions with the nearby [BHB2007]-2 system, and hyperbolic infall, but none fully account for all observed properties. In contrast, a newly identified collimated structure to the west shows clear evidence of gravitationally bound infall. Estimates of its mass, mass infall rate, and angular momentum suggest that this infalling streamer would roughly double the mass budget available to form planets and tilt the disk by a few tens of degrees. Furthermore, its misalignment with the midplane of the disk and the lack of diffuse envelope emission indicate that the streamer may have formed due to gravitational capture of cloud material unrelated to the source’s natal core. Together, these findings support a more dynamic picture of star formation, one where environmental interactions continue to shape the conditions for building planetary systems.

Abstract Galaxies grow alongside central supermassive black holes (SMBHs) through fueling and feedback. However, the origins of this coevolution remain unclear and vary across modeling frameworks. Using semianalytic models (SAMs), we trace SMBH mass assembly across M BH ∼ 10 6−10 M ⊙ . We find significant discrepancies between observations and physics-based models of the local black hole mass function (BHMF), likely from differences in the stellar mass function and scaling relations used to infer the BHMF. Most physics-based models agree at z ∼ 1–4 and broadly match the JWST broad-line active galactic nucleus (AGN) BHMFs at z = 4–5. These models also reproduce the observed bolometric AGN luminosity evolution, except the SAM Dark Sage , which predicts an excess. Interestingly, this pronounced “knee” in the bolometric AGN luminosity function predicted by Dark Sage around L bol ∼ 10 46 erg s −1 is consistent with the inferred abundance and luminosity of “little red dots” at z = 5–6, under the assumption that they are powered entirely by AGN activity. In contrast to other models, Dark Sage deploys multiple growth channels for SMBHs that include mergers, hot-mode accretion, merger-driven cold-accretion, and secular-instability-driven accretion. We analyze the black hole mass buildup and accretion histories in Dark Sage , which, unlike other models, also allows for super-Eddington accretion, and we find that, on average, SMBHs primarily grow through secular disk instabilities and merger-driven cold gas accretion modes. We also find that black hole mergers contribute the majority of the growth of ∼60% of the total mass budget only for the most massive SMBHs by z = 0.

Context . To date, two main mechanisms have been proposed for the formation and growth of nuclear star clusters (NSCs) in galaxies. The first suggests in situ star formation from gas that has migrated to the central regions from the galaxy’s outskirts, while the second involves the accretion of stars from disrupted globular clusters (GCs) onto the galactic centre. However, the relative importance of these mechanisms in the evolution of NSCs across different galaxy morphologies remains an open question. Aims . We investigate the accretion of GC stars on early cosmological timescales through detailed N -body simulations of theoretical GC models to assess the role of this mechanism in Milky Way-like (MW-like) galaxies. Methods . For the dynamical modelling, we used the updated parallel N -body code ϕ-GPU, including stellar evolution. We prepared three sets of GC models with different half-mass radii (r hm ), each consisting of 50 full N -body GC models, and integrated these models in an external, time-variable MW-like potential taken from the cosmological database IllustrisTNG-100. The simulations cover the time interval from −10 Gyr to −5 Gyr, enabling us to assess the rate of early stellar accretion onto the proto-NSC. Results . We find that GC models with average orbital eccentricities of 0.4−0.5 and orbits oriented perpendicular to the galactic disc contribute most significantly to the mass of the proto-NSC formation. Accretion is especially efficient in the first billion years (Gyr) and in compact GC models with r hm =1 pc. In all sets, the dominant accreted stellar population consists of low-mass stars (≈ 0.33 M ⊙ ). However, the accreted mass alone is insufficient to fully account for the current NSC mass. Conclusions . Based on our extended set of numerical simulations, we obtained an average lower limit of mass contribution (≈ 6%) to the NSC from investigated GCs. The fraction of mass contribution from individual disrupted GCs can significantly vary from 0.1% up to 90%. Generally, we conclude that the GC stellar accretion channel alone might not be sufficient to ensure the present-day MW galaxy’s NSC mass budget.

Abstract Dissolved organic matter (DOM) plays a vital role in lakes, but its behavior in winter is poorly understood. This study examined the differences in DOM between lake ice and the upper water column across 18 sites in the Laurentian Great Lakes, integrating in situ sampling and remotely sensed ice data to create a mass budget model to estimate basin‐scale DOM storage and release from ice. We found that the composition of the DOM pool in ice varied based on ice thickness, water DOM composition, nutrients, and dissolved organic carbon concentrations. Calculations of protein‐like, microbial humic‐like, and terrestrial‐like DOM storage in ice under different ice cover scenarios revealed considerable contributions to the upper water column following ice melt, especially for protein‐like DOM which, during extensive ice cover years, contributed an average of 17.7% to the protein‐like DOM pool in spring. This ice‐derived DOM may be an important source of labile carbon for microbial communities, but projected reductions in winter ice cover and duration under climate change may alter DOM dynamics, potentially impacting this important spring carbon subsidy.

Spatiotemporal distributions and mass budgets of artificial radionuclides (137Cs and 239,240Pu) in the seas surrounding Korea.

Abstract. Sea ice has exhibited a number of record lows in both hemispheres over the past two decades. While the causes of individual sea ice lows have already been investigated, no systematic comparison across events and hemispheres has been conducted in a consistent framework yet. Here, the global standalone ocean–sea ice model NEMO4.2.2-SI3 at 1/4° resolution is used to decompose the sea ice mass budget. We separate the relative contributions of ice melt/growth and thermodynamic/dynamic processes, both from a climatological perspective and for selected individual years. The seasonal cycles of Arctic and Antarctic ice mass fluxes show similarities, such as the prevalence of basal growth and melt in the mass budget. The long-term evolution of the mass budget terms reveals an increased importance of basal melt in both hemispheres, at the expense of surface and lateral melt. Regarding sea ice lows, the model indicates that the Arctic summer 2007 anomaly was chiefly caused by dynamic factors, while the Arctic summer 2012 event was rather explained by thermodynamic factors. The Antarctic summer 2022 event was driven by dynamic processes transporting ice towards sectors where more melt than usual occurred. The Antarctic winter 2023 event was characterized by a lack of basal growth. This study emphasises the dominance of processes at the ice-ocean interface in driving the ice mass evolution at all time scales considered here, and highlights the potential of the ice mass budget decomposition to disentangle oceanic and atmospheric contributions in the evolution of the ice state in a changing climate.

Abstract Statistical studies of protoplanetary disks and exoplanet populations often exhibit a “missing mass” problem, where the observed dust masses in (sub)millimeter surveys are significantly lower than expected when compared to the masses of exoplanetary systems. We investigate how the streaming instability and subsequent planetesimal formation in protoplanetary disks might solve this missing mass problem when (sub)millimeter observations are usually interpreted under the assumption of optically thin emission. We conduct hydrodynamical simulations of the streaming instability with self-gravity, after which radiative transfer calculations with dust scattering are performed to measure the (sub)millimeter intensity. The measured intensity is then used to estimate the disk mass under the assumption of optically thin emission and compared to the true mass in the simulation to calculate the observational bias via the mass excess. We find that the emission from overdense filaments that emerges due to the streaming instability is optically thick at (sub)millimeter wavelengths, leading to mass excess factors of ∼2–7.

In May 2024, intense precipitation and flooding impacted southern Brazil in what became the country’s worst climate disaster. The unforeseen volume of runoff was funneled into Patos Lagoon, the world’s largest choked coastal lagoon, transporting large amounts of suspended solids (SS) from the watershed and eroded margins. In this study, we estimate SS concentration, discharge, and mass budget in Patos Lagoon during the May 2024 extreme flood event. Given the challenges of monitoring such extreme events, a multi-proxy approach was adopted, integrating optical satellite data with in situ gravimetric samples, gauging station records, rating curves, and ADCP measurements. Results revealed unprecedented water discharge rates (May 2024 monthly average of 1.78×10 4 m³/s, 37% above the historical maximum) and high SS concentrations (up to 463 g/m³). Between April 1 st and June 30 th , more than 9 million tonnes of SS were delivered to the Patos Lagoon (9.77×10 6 ± 6.75×10 6 t), exceeding the typical annual load and comparable to about one month’s worth of the SS discharge from the Río de La Plata. This study provides the first estimate of the SS mass budget for Patos Lagoon, suggesting that most of the SS was exported to the coastal ocean, while a fraction likely accumulated within the lagoon. These findings offer a foundational understanding of how extreme hydrometeorological events influence sediment dynamics in choked coastal systems.

ABSTRACT Protoplanetary disc mass is one of the most fundamental properties of a planet-forming system, as it sets the total mass budget available for planet formation. However, obtaining disc mass measurements remain challenging, since it is not possible to directly detect H$_2$, and CO abundance ratios are poorly constrained. Dynamical measurements of the disc mass are now possible, but they are not suited to all discs since the measurements typically require well-behaved emission surfaces. A long-standing method is to obtain continuum flux measurements from the dust emission, and convert to a total disc mass by assumption of the dust-to-gas mass ratio, $\epsilon$. This quantity is poorly constrained in protoplanetary discs. We investigate the impact of $\epsilon$ on the morphology of planet-containing hydrodynamical simulations of dusty protoplanetary accretion discs, and suggest that if a planet mass estimate can be obtained, then disc morphology could be used to constrain $\epsilon$ in observed systems relative to each other, improving the total disc mass estimates of protoplanetary discs.

ABSTRACT Using a high-resolution simulation of a dwarf galaxy, we quantify the energetic importance of magnetic fields within the different phases of its interstellar medium (ISM) on parsec scales. We show that, whilst overall the magnetic field is only energetically dominant for a small fraction of the ISM, it becomes important in the thermally unstable regime (45.2 per cent of the mass is magnetically dominant), and dominates in the cold neutral medium (66.1 per cent of the mass). In the molecular gas, the magnetic field dominates more of the total mass budget (39.8 per cent) than thermal energy, turbulent kinetic energy, or gas self-gravitating potential energy. However, much of this mass will be CO-dark. This suggests that magnetic forces are non-negligible during the formation of cold dense gas, which will slow its collapse and lead to an increase in the fraction of cold atomic and molecular gas in the ISM. Consequently, star-forming clouds may be surrounded by a larger reservoir of cold gas than would otherwise be expected.

In this study, we introduce SEDust, a pipeline designed to identify the best-fitting spectral energy distributions from the outputs of the DUSTY code and compare them to observational data. The pipeline incorporates a grid of 24000 models, enabling robust fitting for both carbon- and oxygen-rich AGB stars. It calculates key physical parameters, including luminosity, optical depth, and mass-loss rate, and produces the corresponding best-fit SED plots. Using SEDust, we derived the specific mass-return rates for the galaxies NGC 147 and NGC 185. The specific mass-return rate of AGB stars in NGC 147 is 8.13 × 10−12yr−1 , while in NGC 185 it is 6.52 × 10−11yr−1 . These results indicate that the mass loss from evolved stars alone cannot account for the total mass budget required to sustain these galaxies, highlighting the need for additional sources or mechanisms of mass replenishment to resolve the observed discrepancies.