Earth and Planetary Astrophysics
The Effect of Atmospheric Chemistry on the Optical Geometric Albedos of Hot Jupiters
K. D. Jones, B. M. Morris and K. Heng
We investigate the
geometric albedos of hot Jupiters by comparing observational data from space
telescopes TESS, Kepler, CoRoT, and CHEOPS against theoretical models. The study aims to understand the distribution of observed
geometric albedos across different bandpasses and how these observations align with or deviate from model predictions. We have curated a comprehensive sample of observed
geometric albedos, using either existing Spitzer secondary eclipse measurements or a scaling law between the
equilibrium and dayside temperature to remove any contaminating thermal planetary emission. We then utilised hierarchical
Bayesian modelling to identify trends with planetary properties such as
equilibrium temperature,
gravity, and
stellar metallicity. On a population level, we found no statistical difference in the distributions of
geometric albedos measured by TESS compared to those by Kepler, CoRoT and CHEOPS. We confront the
geometric albedo sample with a simple, but first principles, model that includes Rayleigh scattering by molecular hydrogen and absorption by sodium, water and titanium
oxide and vanadium
oxide. We find that the abundance of sodium and water are the key absorbers that influence the
geometric albedos of hot Jupiters, whilst the addition of titanium
oxide and vanadium
oxide (in the absence of condensation) results in vanishing
geometric albedos that are inconsistent with the observed distributions.
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Earth and Planetary Astrophysics
Mantle Convection and Nightside Volcanism on Lava World K2-141 b
Tobias G. Meier, Claire Marie Guimond, Raymond T. Pierrehumbert et al. (+13 more)
Ultra-short period lava worlds offer a unique window into the coupled
evolution of planetary interior and atmospheres under extreme irradiation. In this study, we investigate the mantle dynamics, nightside volcanism, and volatile outgassing on lava world K2-141 b ($1.54 R_{\oplus}$, $5.31 M_{\oplus}$) using two-dimensional convection models with tracer-based volatile tracking. Our simulations explore a range of interior configurations, including models with and without plastic yielding, basal versus mixed heating, core cooling, and melt intrusion. In models without plastic yielding (i.e. with a strong lithosphere), we find that mantle upwellings form at the substellar and antistellar points, while downwellings form near the day-night terminators at the boundary between the magma ocean and cold, solid nightside. These downwellings facilitate the recycling of crustal material, representing a form of asymmetric, single-lid tectonics. The resulting magma ocean thickness varies from 200 to 300 km depending on the model parameters, corresponding to about 2-3% of the
planet's radius. Continuous nightside volcanism produces a basaltic crust and gradually depletes the mantle of volatiles. We find that over a billion years, volcanic eruptions can outgas tens of bars of CO$_{2}$ and H$_{2}$O. We show that even relatively large volcanic eruptions on the nightside produce thermal emission signals of no more than 1 ppm, remaining below the current detectability threshold in thermal phase curves. However, for most models, outgassing rates are increased near the day-night terminators and future studies should assess whether such localised outgassing could lead to atmospheric signatures in transmission spectroscopy.
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All authors Tobias G. Meier, Claire Marie Guimond, Raymond T. Pierrehumbert, Jayne Birkby, Richard D. Chatterjee, Chloe E. Fisher, Gregor J. Golabek, Mark Hammond, Thaddeus D. Komacek, Tim Lichtenberg, Alex McGinty, Erik Meier Valdés, Harrison Nicholls, Luke T. Parker, Rob J. Spaargaren, Paul J. Tackley
Earth and Planetary Astrophysics
Disc Fragmentation. III. The need for a new paradigm for formation of planets within close binary systems
Luyao Zhang, Sergei Nayakshin, Clement Baruteau et al. (+2 more)
Dozens of
planets and brown
dwarfs are known to orbit one component of tight
stellar binaries ($a_{\rm bin} \lesssim 20$ au), despite circumstellar discs in such systems being truncated to radii of only $\sim (0.2-5)$ au. This presents a challenge to classical
planet formation models, which assume
planets form after their host
stars within stable discs. We propose instead that
planet formation and binary formation are concurrent outcomes of gravitational fragmentation in massive circumstellar discs. In this scenario, rapid disc growth driven by infall from the parent molecular cloud leads to fragmentation at radii of tens of au, producing planetary-mass objects that migrate inward. Continued disc growth produces a dominant "oligarch" fragment that undergoes
accretion runaway to become the secondary
star. During this process, dynamical interactions eject many lower-mass
planets, producing free-floating
planets (FFPs), while others survive if they migrate sufficiently close to the primary
star before destabilisation. Using numerical simulations, we show that survival depends strongly on formation time and mass.
Planets formed early and those with masses $> 1-3M_j$ are preferentially retained, whereas lower-mass
planets ($<0.1M_j$) are typically ejected. This mechanism naturally explains why low-mass
planets are more deficient in tight binaries than gas
giants, and predicts that FFPs have a steeper mass function than bound
planets within binaries.
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All authors Luyao Zhang, Sergei Nayakshin, Clement Baruteau, Philippe Thebault, Eduard I. Vorobyov
Cosmology and Nongalactic Astrophysics · Cross-listed from hep-ph
Radiative Corrections in Supergravity Models of Inflation
John Ellis, Tony Gherghetta, Kunio Kaneta et al. (+2 more)
Supergravity provides the natural supersymmetric framework for early universe cosmology. A broad class of inflationary models in no-scale supergravity yields tree-level predictions for
cosmic microwave background (CMB) observables that closely resemble those of the Starobinsky $R + R^2$ model. Using results from global supersymmetry and supergravity, we analyze radiative corrections in models with canonical and non-canonical kinetic terms, focusing particularly on Starobinsky-like no-scale supergravity models. We derive conditions on the superpotential that keep the gravitino mass finite during inflation and ensure that loop-induced corrections to the Kähler potential remain either finite or subdominant relative to the tree-level potential. We show that in some models, most notably the original no-scale supergravity model with a Wess-Zumino superpotential, radiative corrections grow at large inflaton field values and can dominate the inflationary dynamics, rendering unreliable the model predictions for CMB data. However, we identify a class of no-scale Starobinsky-like models, including the Cecotti model, in which radiative corrections remain very small for inflaton field values $\lesssim 8$ (in Planck units), preserving the agreement of the tree-level predictions with Planck CMB data.
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All authors John Ellis, Tony Gherghetta, Kunio Kaneta, Wenqi Ke, Keith A. Olive
Solar and Stellar Astrophysics
Observations of a Twin Pair of Atypical Solar Flares and a Magnetic-reconnection Scenario
Satyam Agarwal, Alphonse C. Sterling, Shibu K. Mathew et al. (+3 more)
We present observations and a
magnetic-reconnection scenario of a twin pair of "atypical
flares" that occurred on 2022 April 22 in a quadrupolar
magnetic configuration formed by two active regions. The spatio-temporal
evolution of the two
flares is examined using images from the Atmospheric Imaging Assembly (AIA) onboard the
Solar Dynamics Observatory (SDO), and from the ground-based Multi-Application
Solar Telescope (MAST) in Udaipur, India. Characteristic of atypical
flares and indicative of slipping reconnection, the ribbons of each
flare (1) do not spread apart and (2) grow longer by sequential brightening of new
flare kernels. The two atypical
flares are homologous and plausibly have homologous triggers. There are four additional pairs of
flare ribbons, each from a different flaring event that releases much less energy than the atypical
flares. Two of these four pairs are produced by precursors, each possibly triggering one of the two atypical
flares. The remaining two pairs accompany a filament activation, occurring twice within the span of the two atypical
flares. Using a nonlinear force-free field (NLFFF) extrapolation model, we approximate the coronal
magnetic field and find two quasi-separatrix layers (QSLs) that are nearly rooted in the
flare ribbons. The observations and the extrapolated field together suggest a scenario in which the nearly simultaneous occurrence of many reconnections between
magnetic field lines crossing at small angles (slipping reconnection) within each of the two QSLs produces the observed pair of atypical
flares.
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All authors Satyam Agarwal, Alphonse C. Sterling, Shibu K. Mathew, Ronald L. Moore, Qiang Hu, Ramit Bhattacharyya
High Energy Astrophysical Phenomena · Cross-listed from gr-qc
Shadow and Thermodynamics of deformed Schwarzschild-AdS black hole with a Cloud of Strings embedded in Perfect Fluid Dark Matter
Faizuddin Ahmed, Carlos E. Romero-Figueroa and Hernando Quevedo
We investigate the optical and thermodynamic properties of a deformed Schwarzschild Anti-de Sitter (AdS) black hole coupled to a cloud of strings and embedded in perfect fluid dark matter. We analyze the
photon sphere and the corresponding black hole shadow, determining how these observables are affected by the string cloud, dark matter distribution, and
geometric deformation. The thermodynamic behavior is studied through both the quasi-homogeneous fundamental equation within the classical physical approach and the
geometric framework of geometrothermodynamics (GTD), showing full consistency between the two descriptions. In the extended phase space, we examine the critical structure and phase behavior of the system. Our analysis reveals that neither the
geometric deformation nor the dark matter parameter generates new phase transitions; criticality emerges only in the vicinity of the Reissner–Nordström–AdS solution (RN–AdS), where the deformation parameter effectively plays the role of an electric charge squared. These results clarify the interplay between matter distributions,
geometric deformations, and the phase structure of AdS black holes.
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Astrophysics of Galaxies
Particle acceleration and pitch-angle evolution in relativistic turbulence
Daniel Humphrey, Cristian Vega, Stanislav Boldyrev et al. (+1 more)
Synchrotron radiation detected from relativistic astrophysical objects such as
pulsar-wind nebulae and {jets from active
galactic nuclei} depends on the
magnetic fields and the distribution functions of energetic electrons in these systems. Relativistic magnetically dominated
turbulence has been recognized as an efficient mechanism for structure formation and non-thermal particle acceleration in these environments. Recent numerical simulations of relativistic
turbulence have provided insights into the energy distribution functions of accelerated electrons. Much less is currently understood about their {pitch angle distributions}, which are crucial for accurately interpreting the spectra of synchrotron radiation. {We perform a detailed case study of} the pitch angle distributions formed during the process of turbulent acceleration {for $B_0/\delta B_0 = 10$ and $\tilde{\sigma}_0 \sim 40$, where $B_0$ is the uniform component of the
magnetic field, $\delta B_0$ is the fluctuating component, and $\tilde{\sigma}_0$ is the
plasma magnetization based on the
magnetic fluctuations. We find that even minimal numerical noise can cause substantial pitch angle scattering, but we demonstrate techniques for overcoming the numerical challenges associated with the
evolution of very small pitch angles. Our numerical results are consistent with the phenomenological model found in \cite[][]{vega2024b,vega2025}.}
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All authors Daniel Humphrey, Cristian Vega, Stanislav Boldyrev, Vadim Roytershteyn
Cosmology and Nongalactic Astrophysics
Crunching, Bouncing, and Cyclical Cosmologies from Dark Sector Interactions
Marcel van der Westhuizen and Amare Abebe
We present new mechanisms that produce either a future Big Crunch turnaround or a past non-singular bounce in flat FLRW cosmologies within general relativity at the background level, driven solely by non-gravitational interactions between dark matter (DM) and dark energy (DE). We study phenomenological interacting dark energy (IDE) models based on linear kernels of the form $Q = 3H(\delta_{\rm dm}\rho_{\rm dm} + \delta_{\rm de}\rho_{\rm de})$, focusing on parameter regimes with strong energy transfer from dark energy to dark matter. In this strong interacting regime, the interaction does not vanish when one component crosses zero density, allowing one of the dark-sector densities to become negative. The resulting sign changes can violate the energy conditions required for cosmological turnarounds in a flat universe, thereby enabling either (i) a maximum scale factor followed by recollapse into a big crunch, or (ii) a minimum non-zero scale factor corresponding to a bounce. We derive analytic conditions for these turnarounds and obtain closed-form expressions for the associated maximum or minimum scale factor. We also show that, in a closed universe, a special case of the same IDE framework can be tuned to yield a cyclic scenario. Although these strong interaction scenarios are unlikely to describe the observed Universe, they provide a concrete demonstration that exotic cosmological behaviour can arise naturally in underexplored regions of the parameter space of familiar IDE models.
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Instrumentation and Methods for Astrophysics
The Gravitational-wave Optical Transient Observer (GOTO) data pipeline and workflow for transient discovery
J. D. Lyman, D. O'Neill, T. Killestein et al. (+45 more)
Wide-field and high-cadence sky surveys are the first step in the chain of discovery and characterisation of astrophysical transients such as
supernovae, kilonovae, and
tidal disruption events, each linked to the varied demise of
stellar systems. The Gravitational-wave Optical Transient Observer (GOTO) is a
telescope array of thirty-two 40 cm unit
telescopes split over two almost antipodal sites. It performs a regular time-domain sky-survey in the optical to ~20 mag in addition to immediate scheduling of follow-up observations at the locations of external multi-wavelength and -messenger triggers. To facilitate the timely recovery of optical counterparts to these triggers, as well as the presence of serendipitous discoveries of astrophysical transients in the regular sky-survey, a low-latency data pipeline and workflow was developed. The implementation of this workflow is described herein and the quality of GOTO data delivered by it assessed, alongside its performance for
prompt transient recovery. Utilising difference image analysis to identify candidate discoveries, the process is typically complete ~7 minutes after shutter close on the
telescope. We further describe later processing of these candidates – both automated and human-in-the-loop – including reporting to the wider community and the triggering of more detailed observations, with a focus on immediate, intra-night characterisation. The workflow is meeting the needs of GOTO to promptly discover, report and characterise infant transients. Nevertheless, areas for further development and improvements are also highlighted.
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All authors J. D. Lyman, D. O'Neill, T. Killestein, D. Jarvis, A. Kumar, K. Ulaczyk, K. Ackley, P. Chote, M. J. Dyer, M. Pursiainen, D. Steeghs, B. Godson, M. Magee, J. R. Mullaney, B. Warwick, S. Belkin, D. K. Galloway, G. Ramsay, V. S. Dhillon, P. O'Brien, K. Noysena, R. Kotak, R. P. Breton, L. K. Nuttall, B. Gompertz, D. Pollacco, J. Casares, D. L. Coppejans, R. A. J. Eyles-Ferris, O. Graur, L. Kelsey, M. R. Kennedy, A. Levan, S. Littlefair, S. Mandhai, D. Mata Sánchez, S. Mattila, J. McCormac, S. Moran, C. Phillips, K. Pu, A. Sahu, M. Shrestha, E. Stanway, R. L. C. Starling, L. Vincetti, E. Wickens, K. Wiersema
Astrophysics of Galaxies
Not all nitrogen-rich field stars originate from globular clusters
Ellen I. Leitinger, Andrea Miglio, Josefina Montalbán et al. (+7 more)
Globular clusters (GCs) are important tracers of the early
Galactic assembly process, with part of their
stars showing distinct chemical abundance patterns. When such
stars are found in the
Galactic field rather than within GCs, they are assumed to have originated from clusters. We expand the search for such chemically enriched
stars in the Kepler field, targeting
stars located in the
halo, thin and thick disc, to show the potential in using asteroseismology to link the inferred masses and hence, ages, with chemical abundances and kinematics. Using data from APOGEE DR17,
Gaia DR3, and the Kepler mission, we identify
primordial stars as those with chemical signatures typical of field
stars, and enriched
stars as those exhibiting strong nitrogen enrichment, with corresponding carbon and oxygen depletion. We present our sample of 133 red
giant branch and core-He-burning
stars, 92 of which have measured masses and inferred age estimations from asteroseismology. Of the 20 enriched
stars identified, 13 have precise asteroseismic ages, of which a maximum of 3 are old enough ($> 8$ Gyr) to plausibly originate from globular clusters. The inferred asteroseismic ages indicate that most enriched
stars found in the field appear too young to have originated from GCs; however, these apparently young ages are likely the result of assuming single-
star evolution, rather than accounting for binary interactions or mergers. This points to alternative enrichment and evolutionary scenarios, such as mass transfer or coalescence, rather than a globular-cluster origin for most field nitrogen-rich
stars.
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All authors Ellen I. Leitinger, Andrea Miglio, Josefina Montalbán, Davide Massari, Angela Bragaglia, Walter E. van Rossem, Karsten Brogaard, Alessandro Mazzi, Jeppe Sinkbæk Thomsen, Emma Willett
High Energy Astrophysical Phenomena
Rapid jet ejection from PKS 0215+015 coincident with a high-energy neutrino event
F. Eppel, M. Kadler, E. Ros et al. (+19 more)
Aims. We present a new
neutrino-blazar multiwavelength
flare coincidence observed in the blazar PKS 0215+015, which showed a strong multiwavelength outburst in coincidence with the IceCube
neutrino track alert IC220225A, similar to the case of TXS 0506+056. We investigate the immediate response of the
radio jet to the major
flare. Methods. We performed target-of-opportunity observations with the Very Long Baseline Array (VLBA) at 15, 23, and 43 GHz in full polarization for six epochs with monthly cadence following the
neutrino event. We combine the VLBA observations with monitoring data from the Effelsberg 100-m
telescope, the Australia
Telescope Compact Array, and
Fermi/LAT. Results. Based on our VLBI kinematic analysis, we identified a new rapid jet component with an apparent speed of ~60-80c, which was ejected around the arrival of IC220225A. The fast component ejection is traced by a characteristic signature in polarization that suggests a shock-shock interaction with a quasi-stationary feature. By combining the VLBI results with
radio variability data, we estimated a bulk Lorentz factor of $\Gamma = 105 \pm 56$ and a jet viewing angle of $\vartheta = (1.47 \pm 0.31)^\circ$. Conclusions. We note that the properties of the rapid component exceed previously reported maximum apparent jet speeds and Lorentz factors from continuous VLBI monitoring programs. This is likely only possible because we are observing an exceptional flaring event at high
redshift (z=1.72) with higher observing cadence than in typical monitoring programs. We suggest that
neutrino production in PKS 0215+015 can occur through p{\gamma}-interactions with
protons possibly accelerated within the fast-moving feature. The target
photon field could be external to the jet or explained by a multi-layered jet. The latter scenario is consistent with the presence of quasi-stationary features revealed in our analysis.
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All authors F. Eppel, M. Kadler, E. Ros, P. Benke, L. C. Debbrecht, J. Eich, P. G. Edwards, M. Giroletti, A. Gokus, S. Hämmerich, J. Heßdörfer, M. Janssen, S. Kim, D. Kirchner, Y. Y. Kovalev, T. P. Krichbaum, R. Ojha, G. F. Paraschos, F. Rösch, W. Schulga, J. Sinapius, J. Stevens
High Energy Astrophysical Phenomena
Polarisation angle variability in tidal disruption events
A. Floris, I. Liodakis, K. I. I. Koljonen et al. (+9 more)
Tidal disruption events (TDEs) occur when a
star is disrupted by the
tidal forces of a supermassive black hole, and these events produce bright multi-wavelength
flares. Polarimetric measurements of TDEs allow us to disentangle the geometry and the mechanisms characterising the
accretion process. We carried out the first systematic study of the time
evolution of the optical polarisation angle ($\Theta$) in a sample of classified TDEs, combining our own data with all available measurements from the literature, with the goal of testing the currently available models that describe TDE emission. We assembled data from all available observing epochs with significant linear polarisation detections ($\Pi-3\sigma_\Pi>0\%$) for sources with at least two such epochs, and we determined the overall variability trends across the sample in various time frames, such as days from peak time and the fallback time ($t_0$) derived from the different models. Our final sample comprises 12 transients, including three Bowen fluorescence
flares (BFFs). The majority of the sources show significant $\Theta$ variability. The distribution of $|\mathrm{d}\Theta/\mathrm{d}t|$ peaks near ($\sim 2^{\circ}$ d$^{-1}$. BFFs tend to display sustained late-time $\Theta$
evolution, likely due in part to their slower fading. No universal trend emerges when time is normalised by $t_0$. Short-timescale $\Theta$ variability is common in TDEs and is difficult to reconcile with simple axisymmetric reprocessing models that predict a constant polarisation angle. The observed phenomenology favours scenarios with evolving, non-axisymmetric geometries and/or shocks, possibly coupled with changes in optical depth. Denser polarimetric monitoring, contemporaneous spectroscopy, and X-ray/UV coverage are required to break the remaining degeneracies.
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All authors A. Floris, I. Liodakis, K. I. I. Koljonen, E. Lindfors, B. Agìs-Gonzàlez, A. Paggi, D. Blinov, K. Nilsson, I. Agudo, P. Charalampopoulos, J. Escudero Pedrosa, V. Piirola
Cosmology and Nongalactic Astrophysics
Isocurvature Constraints on Dark Matter from Evaporated Primordial Black Holes
G. Franciolini and D. Racco
We revisit the scenario in which stable particles of a dark sector are produced through the complete evaporation of light
primordial black holes (PBHs) formed in the early Universe. We investigate in detail the role of isocurvature perturbations that may arise in this framework. PBHs inherit Poisson fluctuations on unobservable small scales at formation; however, in the presence of
primordial non-Gaussianity that couples long- and short-wavelength modes, these fluctuations can source isocurvature perturbations on cosmological scales. Such perturbations are unavoidably transferred to the dark sector particles emitted via Hawking evaporation. We highlight the potential impact of isocurvature constraints on dark sector particles produced through PBH evaporation. Along the way, we re-assess the constraints on this scenario arising from the overproduction of dark matter (DM), accounting for both PBH evaporation and gravitational production (freeze-in) during (after) inflation, as well as bounds from warm DM and the overproduction of scalar-induced gravitational waves.
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Solar and Stellar Astrophysics
Latitude-Dependent Time Variations of the Solar Tachocline
Sarbani Basu, Sylvain G. Korzennik and Sushanta C. Tripathy
We have examined how the characteristics of the tachocline – i.e., the change in rotation rate $\delta\Omega$, or the "jump", the position of the midpoint of the tachocline, $r_d$, and the width of the tachocline, $w_d$, – change as a function of time at different latitudes using 30 years of helioseismic data obtained by the GONG network. We find a statistically significant change in the jump, however, these changes do not have a simple correlation with
solar activity. The dependence is different for
solar Cycles 23 and 24, and for Cycle 25, it is more similar to that of Cycle 24. While our measured changes of the tachocline's width with time are marginally statistically significant, {the cross correlation is statistically significant and implies that the width is larger when the
solar activity is smaller, suggesting that
magnetic fields play a role in confining the tachocline. The position of the tachocline shows a significant secular change at low latitudes ($< \simeq 50^\circ$).} At these latitudes, the tachocline has been moving steadily closer to the base of the convection zone. This is consistent with other measurements that have shown that the overall complexity of
solar activity has been decreasing over the last few decades. It leads us to speculate that strong
magnetic fields tend to push the tachocline deeper into the radiative zone.
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Solar and Stellar Astrophysics
Negative superhumps in cataclysmic variables driven by retrograde apsidal disk precession
David Vallet, Rebecca G. Martin, Stephen H. Lubow et al. (+1 more)
Negative superhumps are photometric modulations in cataclysmic variables with periods slightly shorter than the orbital period. They are usually attributed to retrograde nodal precession of a tilted
accretion disk, although the origin and persistence of the tilt remains unexplained. We propose instead that negative superhumps arise from retrograde apsidal precession of an eccentric disk. Using linear eccentric disk theory, we show that the direction of apsidal precession is highly sensitive to disk size and temperature, and that pressure effects can drive retrograde precession even in cool disks. In low mass ratio systems where the 3:1 resonance is within the disk, disk expansion during outbursts may produce opposite precession directions in the inner and outer disk, allowing the temporary coexistence of positive and negative superhumps, and driving dissipation in an extended superoutburst. In higher mass ratio systems where the resonance location is outside of the disk, the resonance width can still extend into the outer parts of the disk, excite eccentricity, and drive apsidal precession. This mechanism explains the prevalence of negative superhumps across a wide range of mass ratios and
accretion states, without requiring a long-lived disk tilt. It may also explain how positive superhumps can occur in high mass ratio systems if the disk density builds up in the outer parts of the disk.
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All authors David Vallet, Rebecca G. Martin, Stephen H. Lubow, Stephen Lepp
Cosmology and Nongalactic Astrophysics
The ESPRESSO Redshift Drift Experiment III – The Third Epoch of QSO J052915.80-435152.0
Andrea Trost, Catarina M. J. Marques, S. Cristiani et al. (+25 more)
The Sandage-Loeb test probes
cosmic expansion directly by measuring the
redshift drift in
quasar absorption features in a model-independent way. In this series of papers, we have launched an observational campaign to assess whether current instrumentation is capable of measuring this effect and what systematic effects might interfere with a detection. We report the observations and analysis of the third epoch of ESPRESSO observations of the bright
quasar J052915.80-435152.0 (SB2, z=3.962), extending the temporal baseline to $\sim2$ years, and providing the tightest constraints on the
redshift drift in the series so far. We acquired 9.5 hours of ESPRESSO observations, complementing the 12 hours presented in the first paper of the series, with one year of separation from the second epoch. The complete
dataset was analysed and compared to spline-based Lyman-$\alpha$ forest models calibrated on simulations, to measure the presence of any velocity drift among the spectra. The measurement was carried out with two independent methods. Both approaches give a consistent null result, $\dot{v} = -3.5 \pm 3.6 ~{\rm m s^{-1} yr^{-1}}$ (or $\dot{z} = (-5.3\pm5.6)\times 10^{-8}~{\rm yr^{-1}}$ in
redshift space), in agreement with $\Lambda$CDM expectations, systematic effects remain subdominant at the present level of noise. By extrapolating the results from the observed sightline to the complete QUBRICS Golden Sample, we show that ESPRESSO alone could detect the signal on century timescales, while a joint ESPRESSO+ANDES programme would reach first detection before 2080. A future analysis of the other
quasars of the QUBRICS Golden Sample is required to improve this estimate. We show that the program would greatly benefit from a complementary effort with
radio facilities targeting low-z HI 21 cm absorption lines. Such synergy could reduce the experiments' timeline by up to $\sim10$ years.
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All authors Andrea Trost, Catarina M. J. Marques, S. Cristiani, Guido Cupani, Simona Di Stefano, Valentina D'Odorico, Francesco Guarneri, Carlos J. A. P. Martins, Dinko Milaković, Luca Pasquini, Ricardo Génova Santos, Paolo Molaro, Michael T. Murphy, Nelson J. Nunes, Tobias M. Schmidt, Yann Alibert, Konstantina Boutsia, Giorgio Calderone, J. I. González Hernández, Andrea Grazian, Gaspare Lo Curto, Enric Palle, Francesco Pepe, Matteo Porru, Nuno C. Santos, Alessandro Sozzetti, Alejandro Suárez Mascareño, Maria R. Zapatero Osorio
Astrophysics of Galaxies
Synthetic Spectral Library of Optically Thick Atmospheres for Little Red Dots
Hanpu Liu, Yan-Fei Jiang, Eliot Quataert et al. (+3 more)
Little Red Dots (LRDs) challenge conventional models of active
galactic nuclei. At rest-optical-to-near-infrared (IR) wavelengths, these compact extragalactic objects show blackbody-like continuum emission and spectral features reminiscent of
stars, motivating models with an optically thick atmosphere at $T_{\rm\!\,eff}\sim4000-5000{\rm~K}$. We develop (and publicly release) a synthetic spectral library of optically thick atmospheres with gas conditions tailored for LRDs, parameterized by effective temperature $T_{\rm\!\,eff}$ and surface
gravity $g$. Given the uncertain dynamical structure of LRDs, we interpret $g$ mainly as a proxy for the photospheric density $\rho_{\rm\!\,ph}$. We show that blackbodies are only crude approximations to the emission from LRD-like atmospheres. Spectral features are abundant, many of which are sensitive diagnostics of photospheric density, including the overall
curvature of the continuum, the rest-$1.6{\rm~\mu m}$ “kink” from $\rm H^-$ opacity, and the Ca~II triplet (CaT) absorption at rest-$8500~\mathring{A}$. When compared against a local LRD, the Egg, all three features are consistent with a low photospheric density $\rho_{\rm ph}\sim10^{-11}{\rm~g~cm^{-3}}$ ($g\sim10^{-3}{\rm~cm~s^{-2}}$ in our library), although CaT alone admits another higher-density solution. This low $\rho_{\rm ph}$ directly results from our radiative transfer modeling; with the additional assumption that the CaT line width traces turbulent support at the continuum photosphere in a spherical geometry, we infer a mass within the photosphere (black hole plus gas) of $\sim10^4~M_\odot$, with an Eddington ratio $\lambda_{\rm Edd}\gtrsim20$. For higher-
redshift LRDs, we advocate for rest-near-IR spectroscopic surveys and high-resolution spectra of potential absorption lines as a test of the optically thick atmosphere scenario and as a unique probe of the central engine mass.
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All authors Hanpu Liu, Yan-Fei Jiang, Eliot Quataert, Jenny E. Greene, Yilun Ma, Xiaojing Lin
High Energy Astrophysical Phenomena
The Role of the Heliosphere in Shaping the Observed Cosmic Ray Spectral Anisotropy
Vanessa López-Barquero, Andrés Marín Portuguez, Paolo Desiati et al. (+1 more)
Experimental results by Milagro, HAWC, and ARGO-YBJ have observed variations in the energy spectrum of
cosmic rays at TeV scales in different regions of the sky. These findings on the spectral anisotropy provide insights into
cosmic ray behavior. This work explores the impact of
galactic cosmic ray interactions with the heliosphere in creating the observed spectral anisotropy features. Specifically, the features around 1-10 TeV, where our previous studies on the heliosphere have shown the greatest effects. In this project, we integrate particle trajectories in a state-of-the-art MHD-kinetic heliosphere model that includes the effects of the
solar cycle and interaction with the interstellar medium's
magnetic field. With these elements, this is the first time the exact effects of the heliosphere's
magnetic field are tested to determine their influence on
galactic cosmic rays and their spectral anisotropy. In our results, we identified an area on the map that exhibits a distinct
cosmic ray energy spectrum compared to the all-sky distribution. This area approximately coincides with Region A, where observations have found a harder energy spectrum than the isotropic spectrum.
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All authors Vanessa López-Barquero, Andrés Marín Portuguez, Paolo Desiati, Juan Carlos Díaz-Vélez
Solar and Stellar Astrophysics
Constraints on White Dwarf Hydrogen Layer Masses Using Gravitational Redshifts
Stefan M. Arseneau, J.J. Hermes, Maria E. Camisassa et al. (+2 more)
The hydrogen envelope is the outermost layer of a DA white
dwarf; it makes up the entirety of the
stellar photosphere, and yet its typical extent is difficult to model theoretically and remains poorly observationally constrained. As a result, hydrogen envelope mass is a substantial source of systematic uncertainty in physical properties of white
dwarf, including overall masses and cooling ages. In this work, we fit a Gaussian mixture model to gravitational
redshifts from high-resolution spectroscopy, paired with radius measurements from
Gaia BP/RP spectra, to measure the mass-radius relation for a sample of 468 white
dwarfs. Our results are in excellent agreement with the predicted mass-radius relations of state-of-the-art evolutionary models, including those from the MESA Isochrones and
Stellar Tracks (MIST) library. We find that mass-radius relations such as MIST which assume a thick and mass-dependent hydrogen envelope are preferred by the observed probability density function over models which assume a constant hydrogen envelope mass. Proper treatment of the
evolution of white
dwarf progenitors is thus important for accurately modeling the mass-radius relation. Our results indicate that gravitational
redshift measurements of large samples of white
dwarfs in wide binaries are promising probes of the hydrogen envelope masses of DA white
dwarfs.
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All authors Stefan M. Arseneau, J.J. Hermes, Maria E. Camisassa, Roberto Raddi, Evan B. Bauer
Solar and Stellar Astrophysics
High Velocity Circumstellar Gas Orbiting a White Dwarf Star
B. Zuckerman, Érika Le Bourdais, Beth L. Klein et al. (+6 more)
Numerous white
dwarf stars are known to be orbited by disks of gas and
dust. To date, broad, about 300 km s-1 wide, gaseous circumstellar absorption features have only been reported for the already iconic WD 1145+017, where one is witnessing the breakup of an extrasolar asteroid in real time. We report here the discovery of absorption from circumstellar gas around a second white
dwarf (WD J0234-0406) with similarly broad features. The observed lines are carried by ions of Ca, Cr, Fe, Ti, Mg, Mn, Na, O, Si, Sc, Sr, Ti, and V. In addition, deep, non-photospheric lines of Si IV are seen in the ultraviolet; we compare these with Si IV lines previously seen in the ultraviolet spectra of various other white
dwarfs. The apparent broadband flux of WD 1145+017 is known to change often and rapidly as chunks of the asteroid pass between the
star and Earth. No such variations are seen in the brightness of WD J0234-0406. In addition, while the strength/structure of circumstellar absorption features at WD 1145+017 has changed dramatically with time, nothing similar is seen at WD J0234-0406. Excess infrared emission at WD J0234-0406 indicates the presence of circumstellar
dust particles.
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All authors B. Zuckerman, Érika Le Bourdais, Beth L. Klein, Patrick Dufour, Carl Melis, Alycia J. Weinberger, Siyi Xu, Antoine Bédard, Detlev Koester
Solar and Stellar Astrophysics
Bridging the Prandtl number gap: 3D simulations of thermohaline convection in astrophysical regimes
Adrian E. Fraser
Thermohaline convection (also known as fingering convection or thermohaline mixing) occurs in
stellar radiation zones where a sufficient inversion of the mean molecular weight is present. This process mixes chemicals radially and occurs in a variety of
stars, including near the luminosity bump on the red
giant branch and potentially in polluted white
dwarfs. Previous efforts to characterize this process using 3D simulations have been restricted to regimes far from actual
stars: The Prandtl number $\Pr$–the ratio of the kinematic viscosity to thermal diffusivity–assumes values as low as $10^{-6}$ in
stars, but 3D simulations have been restricted to $\Pr \gtrsim 10^{-2}$. For this reason, disagreements between observations and simulations are routinely dismissed as stemming from this $\Pr$ gap. This letter bridges this gap and demonstrates that 3D simulations of thermohaline convection can be performed in
stellar parameter regimes. Using a suite of simulations spanning previously studied regimes with $\Pr \gtrsim 10^{-2}$ down to $\Pr = 10^{-6}$, we demonstrate that the chemical mixing model of Brown, Garaud, & Stellmach (2013) remains consistent with 3D simulations across both regimes. Therefore, tensions between this model and observations cannot be dismissed as resulting from a $\Pr$ gap, and must be resolved by considering additional physics.
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High Energy Astrophysical Phenomena
Two-body relaxation in the EMRI-TDE disk model for Quasi Periodic Eruptions
Chiara Maria Allievi, Luca Broggi, Alberto Sesana et al. (+1 more)
Quasi Periodic Eruptions (QPEs) are luminous bursts of soft X-rays recently discovered in
galactic nuclei. They repeat on timescales of hours to weeks, superimposed to an otherwise stable quiescent X-ray level, consistent with emission from a radiatively efficient
accretion flow around relatively low-mass MBHs. Although their physical origin is still debated, their quasi-periodicity naturally arises within the 'impact model', in which the X-ray bursts are generated by the interaction between an sBH or a
star in a close orbit around the central MBH and the
accretion disk formed by a
tidal disruption event (TDE). While this model is consistent with the phenomenology of QPEs, it remains unclear whether such specific physical configurations are sufficiently commonto explain the observed QPE number density. We present the first end-to-end quantitative calculation of the expected QPE rate and abundance within the framework of the impact model. To this purpose, we combine the rates of TDEs and extreme mass-ratio inspirals (EMRIs) around MBHs spanning a range of masses masses. We employ the public code PhaseFlow to simulate seven systems with MBH masses between $10^5 M_\odot$ and $10^8 M_\odot$, each sourronded by a three-component population: one composed of $1M_\odot$
stars, and two consisting of sBHs with masses of $10M_\odot$ and $40 M_\odot$. Based on the emission constraints available in the literature, we restrict to sBH EMRIs on prograde orbit with eccentricity $e<0.5$ and inclination $\iota<20^{\circ}$ with respect to the
accretion disk. For
stellar EMRIs the constraints instead arise from the requirement that the
star avoid
tidal disruption. We find that the predicted QPE number density spans the range $10^{-12} \rm Mpc^{-3}$ to $10^{-6} \rm Mpc^{-3}$, depending on the assumed orbital period interval and on the adopted eccentricity and inclination thresholds.
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All authors Chiara Maria Allievi, Luca Broggi, Alberto Sesana, Matteo Bonetti
Astrophysics of Galaxies
Reconciling 3D Models for the Central 10 parsecs of the Milky Way
Elisabeth A.C. Mills, Natalie O. Butterfield, Hauyu Baobab Liu et al. (+13 more)
The construction of an accurate 3D model of the Milky Way center is necessary to understand inflow processes that drive its overall
evolution, and to compare our
Galactic nucleus to other
galaxies'
nuclei. A main point of contention is the line-of-sight location of sources observed toward the central 10 pc of the
Galaxy, including recent
star formation (the Sgr A East
supernova remnant and Sgr A HII regions) and copious gas (the 50 and 20 km/s molecular clouds, the Circumnuclear Disk, and the Sgr A West ionized "minispiral" that encircles the central supermassive black hole, Sgr A*). Some models place all of these structures within a radius of 5 pc from Sgr A*, while others place the 20 and 50 km/s clouds at a distance of at least 30 - 50 pc away from Sgr A* along the line of sight. We present new
radio and millimeter observations of the molecular gas toward the central ~10 pc, from which we have constructed an alternative 3D model that is consistent with both prior
radio observations and orbital gas kinematics. Our model places the 20 km/s cloud, 50 km/s cloud, and Sgr A East more than 10 pc in front of Sgr A*. While this model does not conclusively rule out a connection between the 50 and 20 km/s clouds and the circumnuclear disk, we argue that prior evidence for these connections is tenuous, especially given the complex spatial and kinematic overlap of structures along the line of sight.
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All authors Elisabeth A.C. Mills, Natalie O. Butterfield, Hauyu Baobab Liu, Dani Lipman, Adam Ginsburg, Mattia C. Sormani, Jonathan D. Henshaw, Cara D. Battersby, Ashley T. Barnes, Simon C. O. Glover, Francisco Nogueras-Lara, Mark R. Morris, Juergen Ott, Cornelia Lang, Claire Cook, Xinyu Mai
Earth and Planetary Astrophysics
Ground-based Atmospheric Characterization of Super-Earth L 98-59 d at High Spectral Resolution
Connor J. Cheverall, Nikku Madhusudhan, Savvas Constantinou et al. (+1 more)
Atmospheric characterization of
exoplanets using ground-based high-resolution transmission spectroscopy has traditionally focussed on large and close-in
planets, such as hot Jupiters. In this work, we aim to extend this technique to smaller and more temperate
planets by studying the atmospheric composition of the temperate super-Earth
planet L 98-59 d ($\sim$$1.5\,\mathrm{R_{\oplus}}$; $\sim$$1.9\,\mathrm{M_{\oplus}}$). Using high-resolution transmission spectra obtained using IGRINS on the Gemini-South
telescope, we demonstrate the feasibility for atmospheric characterization of super-Earths using ground-based facilities, and confirm the previous tentative JWST inference of hydrogen sulfide (H2S) in the atmosphere of L 98-59 d at $\lesssim$3.9$\,\sigma$ ($B\sim390$). This is the first ground-based inference of a molecular species in the atmosphere of a super-Earth
planet, and reveals the sensitivity of spectrographs on 8m-class
telescopes to the atmospheric characterization of such
planets. By exploring a grid of atmospheric models, we find that the data favors a cloud-free atmosphere with an abundance of H2S corresponding to $\sim$1-10$\times$
solar metallicity. We additionally place constraints on the atmospheric abundances of other molecular species. Assuming cloud-free models, super-
solar abundances for CH4 and NH3 are ruled out at 3.6$\sigma$ and $4.6\sigma$, respectively. Our results are consistent with previous suggestions that L 98-59 d is a super-Earth with possible disequilibrium production of H2S driven by volcanic outgassing from the surface. Future studies combining multiple observations with different facilities may be able to further constrain the atmospheric composition of this
planet. This work underscores the promise of atmospheric characterization of super-Earth
exoplanets using high-resolution spectroscopy with ground-based facilities.
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All authors Connor J. Cheverall, Nikku Madhusudhan, Savvas Constantinou, Peter R. McCullough
Earth and Planetary Astrophysics
Predicting Gaia astrometry's ability to constrain the populations of circumbinary planets
Thomas A. Baycroft, Amaury H.M.J Triaud and Johannes Sahlmann
The coming data releases of
Gaia are expected to result in an upheaval of
exoplanet science, in particular for long period
giant planets ($0.2 {\rm M_{J}} \leq M\leq25 {\rm M_{J}}$). One class of
exoplanets which
Gaia will help investigate is circumbinary
planets. Using the current knowledge of the circumbinary
exoplanet population as well as expectations for the
Gaia sensitivity, we investigate the impact
Gaia will have on our understanding of circumbinary
planets. We compare our results to a pre-launch estimate, the main differences arising from a better understanding of the circumbinary
planet population, which result in a lower expected yield than previously predicted, though still significant compared to the known population. We make a rough yield estimate, with conservative detection criteria and parameter-space cuts, predicting in the 10s - 100s of detections in
Gaia DR4. More importantly, we show how the yield estimate varies strongly with different assumptions on the injected circumbinary population, showing
Gaia's sensitivity to the mass and orbital period distribution of circumbinary
planets. We find that
Gaia circumbinary
exoplanet detections will be biased towards
planets closer to the instability zone surrounding the binary, due to the larger number of binaries on wider orbits and the limited timespan of
Gaia. We also assess the impact
Gaia will have on known circumbinary systems, one being that it may resolve the question of reliability of the claimed
planets orbiting post-common-envelope binaries, with
Gaia DR5 being sensitive to between 3 and 11 out of 32 such
planet candidates.
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Cosmology and Nongalactic Astrophysics
Interpreting map-based $E$/$B$ spectral properties of CMB foregrounds
Gilles Weymann-Despres, Léo Vacher, Michael E. Jones et al. (+5 more)
Map-space $E$/$B$ decompositions of linear polarization are attractive for foreground and CMB analyses because they separate parity families: $B$-family patterns directly contaminate
primordial tensor searches, while $E$-family patterns trace coherent
Galactic structures. However, the $E$/$B$ transform is not fully local and can induce apparent spectral complexity even when the underlying sky is spectrally simple in $\underline{P}=Q+iU$. We quantify this effect for synchrotron emission using complex log–Taylor and moment expansions for $\underline{P}$, its
spin-preserving projections $\underline{P}_E$ and $\underline{P}_B$, and its more standard scalar projections $E$ and $B$. We relate the coefficients of these expansions to physical mechanisms such as line-of-sight mixing, synchrotron ageing, and Faraday effects. Using simple sky models, we show how $\underline{P}_E$ and $\underline{P}_B$ reorganize the spectral behaviour of $\underline{P}$ into parity families with a clear
geometric meaning. They retain interpretable amplitudes and angles and satisfy the closure relation $\underline{P}=\underline{P}_E+\underline{P}_B$, which extends to all moment orders. By contrast, scalar quantities such as $|E|$ and $|B|$ show larger induced variability of effective spectral parameters and enhanced spectral complexity, while $E+iB$ lacks interpretable polarization amplitude and angle. Finally, we present simple CMB-oriented applications: three-frequency diagnostics to test whether the sky is better described by a power law in $P$ or by separate effective laws in $(P_E,P_B)$, and idealized ILC and masking examples showing that the preferred map-space field depends on where foreground simplicity and residual contamination reside. This framework provides practical diagnostics for choosing foreground modelling, cleaning, and masking strategies in
Galactic and CMB $B$-mode analyses.
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All authors Gilles Weymann-Despres, Léo Vacher, Michael E. Jones, Angela C. Taylor, Carlo Baccigalupi, A.J. Banday, Richard D.P. Grumitt, Nicoletta Krachmalnicoff
High Energy Astrophysical Phenomena
Low-$T/|W|$ instabilities in differentially rotating neutron stars resembling merger remnants
Georgios Lioutas, Panagiotis Iosif, Andreas Bauswein et al. (+1 more)
We construct constant rest-mass sequences of
equilibrium models of differentially rotating
neutron stars which resemble binary
neutron star post-merger remnants. For a more realistic description of the post-merger remnant, we impose that each model carries approximately $95\%$ of the angular momentum that a binary system with the same total rest-mass has at the moment of merging, based on an empirical relation informed from
neutron star merger simulations. We account for equation of state effects by employing two distinct microphysical descriptions for high density matter. We dynamically evolve the
equilibrium models with a three-dimensional general relativistic hydrodynamics code that employs the conformal flatness approximation. We investigate the connection between the occurrence of the instability and the existence of corotation radii within the
stellar configurations and determine the instability window for both equation of state sequences. The occurrence of low-$T/|W|$ instabilities leads to pronounced gravitational wave emission in the range $0.13 \lessapprox\beta \lessapprox 0.2$, while models outside this range exhibit less pronounced features in the gravitational wave spectrum. The prominence of gravitational wave emission is primarily determined by $\beta$, while the equation of state seems to have a more minor effect. We present correlations between the strength of the gravitational wave emission associated with the instability and properties of the
equilibrium models.
Stellar configurations modelled by different equations of state display differences in the timescales over which the various dynamical features develop, as well as whether they exhibit a pronounced $m=1$ deformation. Potential relations between the instability growth timescales and properties of the
stellar models are studied.
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All authors Georgios Lioutas, Panagiotis Iosif, Andreas Bauswein, Nikolaos Stergioulas
Cosmology and Nongalactic Astrophysics
A Template-Based Search for Large-Scale-Structure–Correlated Anisotropy in the Nanohertz Gravitational-Wave Background Using the Public NANOGrav 15-Year Data Set
Yun Fang
Recent PTA analyses reporting evidence for a nanohertz common-spectrum process motivate targeted tests of whether any anisotropic component of the
stochastic gravitational-wave background (SGWB) is correlated with the nearby large-scale structure (LSS), as anticipated for an astrophysical background dominated by supermassive black hole binaries. We present the first
Bayesian PTA likelihood analysis that embeds an externally observed, full-sky
galaxy-survey LSS template directly as an overlap-reduction-function (ORF) component. Using the 2MASS Photometric
Redshift (2MPZ)
galaxy catalog, we construct low-multipole LSS–correlated ORF templates in two
redshift slices ($0<z\le0.1$ and $0.1<z\le0.2$) and model PTA cross-correlations as $\Gamma_{ab}=\Gamma^{\rm HD}_{ab}+\sum_i \epsilon_i\,\Gamma^{\rm LSS(i)}_{ab}$, where $\epsilon_i$ quantifies the amplitude of an SGWB component whose angular correlations project onto the fixed 2MPZ LSS templates. Applying this framework to the NANOGrav 15-year
dataset, we find no evidence for an LSS-correlated component: the inferred $\epsilon_i$ values are consistent with zero in both single-bin and two-bin analyses (e.g., $\epsilon_1=0.20^{+1.68}_{-1.66}$ and $\epsilon_2=-0.11^{+2.04}_{-1.83}$; 68% credible intervals), and Bayes factors favor the isotropic Hellings–Downs hypothesis ($\mathcal{B}_{{\rm HD+LSS}_1,{\rm HD}}=0.40$, $\mathcal{B}_{{\rm HD+LSS}_2,{\rm HD}}=0.43$, $\mathcal{B}_{{\rm HD+LSS}_{1+2},{\rm HD}}=0.11$). We therefore place upper limits on any 2MPZ-traced, LSS-correlated contribution to the SGWB at $z<0.2$. More broadly, our framework provides a reproducible pathway for incorporating observed LSS information into PTA anisotropy searches and naturally motivates extensions to finer
redshift tomography and next-generation PTA
datasets.
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Instrumentation and Methods for Astrophysics
The statistical properties of the cross spectrum
Edward J. R. Nathan, Adam Ingram, Daniela Huppenkothen et al. (+2 more)
The cross spectrum encodes the correlated variability between two time signals. In recent years, the cross spectrum has been used to study astronomical sources, particularly in the field of X-ray timing. In the literature, it has been common to either simultaneously fit the real and imaginary components of the cross spectrum, or fit the phase and magnitude. Until now, a full discussion of the statistical distribution of the cross spectrum has been missing from the astronomical literature. In this paper, we present a derivation of the full statistical distribution of a cross spectrum between two time series, showing that it follows an asymmetric Laplace distribution. We further provide the probability distribution function for a cross spectrum random variable, along with the marginal distributions for many quantities. We also relate the cross spectrum to the power spectra of the constituent time series. This work will enable the cross spectrum to be used more accurately as a probe of physical processes such as
accretion onto black holes and
neutron stars.
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All authors Edward J. R. Nathan, Adam Ingram, Daniela Huppenkothen, Matteo Bachetti, Javier A. García
Earth and Planetary Astrophysics
The ALMA Survey of Gas Evolution of PROtoplanetary Disks (AGE-PRO): Constraints on disk turbulence, fragmentation velocity, and inner pebble fluxes
Lilian Luo, Paola Pinilla, Camila Pulgarés et al. (+14 more)
How substructures and disk properties affect
dust evolution and the delivery of solids and volatiles into
planet-forming regions remains an open question. We present results from tailored
dust evolution modeling of the AGE-PRO ALMA large program, a sample of 30 protoplanetary disks spanning different evolutionary stages. Visibility fitting of the AGE-PRO ALMA data (at 1.3\,mm) reveals that approximately half of the disks exhibit radial substructures. Combined with
stellar properties, disk inclinations, and gas mass estimates from CO isotopologues and N$_2$H$^+$, this well-characterized set of disks provides an ideal testbed to constrain
dust evolution models across different ages and disk morphologies. Using the
dust evolution code DustPy, we simulate
dust evolution in each disk under four model configurations, varying two key free parameters: the turbulent viscosity ($\alpha = 10^{-4}, 10^{-3}$) and fragmentation velocity ($v_{\rm{frag}} = 1 \mathrm{m\,s^{-1}}, 10 \mathrm{m\,s^{-1}}$). Pressure traps are incorporated by perturbing the gas surface density based on the continuum intensity profiles, and synthetic observations generated with RADMC-3D are compared to these profiles. While no single model fits all disks, nearly half are best reproduced by the configuration with low
turbulence and low fragmentation velocity ($\alpha = 10^{-4}, v_{\rm{frag}} = 1\,\mathrm{m\,s^{-1}}$). Models of smooth disks underpredict
dust mass, possibly indicating unresolved substructures. Pebble fluxes into inner disk regions correlate more strongly with disk age than with the presence of substructures, highlighting time-dependent
dust transport as a key factor in shaping inner disk composition. Our results also provide a comparative baseline for interpreting multiwavelength and JWST water vapor observations.
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All authors Lilian Luo, Paola Pinilla, Camila Pulgarés, Laura M. Pérez, Miguel Vioque, Nicolás T. Kurtovic, Anibal Sierra, Carolina Agurto-Gangas, Rossella Anania, John Carpenter, Lucas A. Cieza, Dingshan Deng, James Miley, Ilaria Pascucci, Giovanni P. Rosotti, Benoît Tabone, Ke Zhang