Astrophysics of Galaxies
A model to mini-quench early galaxies by balancing stellar feedback and gas accretion
Judah Luberto and Steven R. Furlanetto
The James Webb Space
Telescope (JWST) has discovered a population of low-mass, early
galaxies with very low levels of
star formation over tens of Myr. These "mini-quenched"
galaxies were one of the many surprises from JWST and still require a robust explanation. We seek to explain a few important properties of these
galaxies, namely the timescales governing their
star formation and quenching. We use a simple model that pairs stellar feedback with the forces binding gas to a $z \sim 6$
galaxy, and with plausible parameter choices, this model produces mini-quenching in
galaxies approximately as large as observed mini-quenched
galaxies – up to total stellar masses of $\sim 10^{10} M_{\odot}$. In our model, the ejected interstellar gas forms into a spherical shell that expands outward during quenching. Our novel improvement is allowing this expanding shell to prevent accreting gas from falling in, in contrast to other models whose shells do not interact with accreting gas. Using our model, if a
galaxy accretes isotropically, we find that stellar feedback can reproduce observed timescales of mini-quenching with plausible
galaxy-formation parameter values. However, at low
halo masses, the quenching timescale of our model is too long ($> 100$ Myr). A potential solution for a long quenching time is for the
galaxy to accrete via filaments, in which case only a portion of the shell interacts with the accreting gas and the quenching timescale decreases to more accepted values. However, the ram pressure from feedback cannot stop filaments with very small opening angles, as occur in some
halo formation models, making mini-quenching impossible. Finally, we use this model to estimate the fraction of
galaxies undergoing mini-quenching, finding that it can be large.
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High Energy Astrophysical Phenomena
A Significant Dust Reservoir Uncovered with JWST in the Type Ic SN 1983V More Than 40 Years Post-Explosion
Sophia S. Kressy, Thomas Moore, Ori D. Fox et al. (+26 more)
Searching for late-time emission from
supernovae (SNe) is an active field. Infrared (IR) wavelengths are sensitive to thermal emission from dust, which can be used to probe SN contributions to the
cosmic dust budget and progenitor mass-loss histories. The older an SN, the more likely it is for any existing dust to have cooled below the detection threshold of most observatories, even JWST. Decades-old IR observations of SNe are therefore exceedingly rare. Here we present fortuitous and serendipitous JWST IR observations that detect a point source at the position of the Type Ic SN 1983V more than 40 yr post-explosion. We demonstrate that the source is unlike nearby HII regions and likely to be the dusty SN. We further show evidence from archival HST data of a plausible H/alpha counterpart associated with ongoing SN shock interaction that collisionally heats the dust. In this scenario, the dust is distributed in a
torus, more consistent with mass loss from binary interaction than a spherical wind. While not the oldest SN detected by JWST (SN 1980K), SN 1983V is a close second. Moreover, it has a relatively large dust mass (~7.7 x 10^-3 M_solar), particularly for a stripped-envelope SN. Although the dust is not likely newly formed, it does suggest such systems may contribute to dust production, particularly in the early Universe where massive
stars and binary systems were more common. Spectroscopic observations can ultimately confirm the SN nature of this source.
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All authors Sophia S. Kressy, Thomas Moore, Ori D. Fox, Nathan Smith, Raphael Baer-Way, Luc Dessart, Michael J. Dulude, W. V. Jacobson-Galán, Melissa Shahbandeh, Tea Temim, Chris Ashall, David A. Coulter, Alexei V. Filippenko, Sebastian Gomez, Jacob Jencson, Kyle Medler, Daniel Patnaude, Tamás Szalai, Schuyler D. Van Dyk, Aiden Agostinelli, Sarah Healy, Zachary G. Lane, Dan Milisavljevic, Shazrene Mohamed, Benjamin Radmore, Armin Rest, Arkaprabha Sarangi, Yossef Zenati, Noah Zimmer
Cosmology and Nongalactic Astrophysics
On the Clustering Bias of Unresolved Gamma-Ray Sources
Bhashin A. Thakore, Marco Regis, Michela Negro et al. (+4 more)
The Unresolved $\gamma$-Ray Background (UGRB) encodes the collective emission of source populations that are too faint to be detected individually, and its cross-correlation with tracers of the large-scale structure has emerged as a powerful tool to characterize those populations. In this work, we analyze the weak-
lensing–UGRB cross-correlation using a reference blazar model. By modeling the relation between blazar $\gamma$-ray luminosity and host-
halo mass, we infer the average linear bias $\langle b(z) \rangle$ and host-
halo mass $\langle M(z) \rangle$ of the unresolved blazar population. We find that the signal is dominated by moderately biased sources, with $\langle b \rangle \gtrsim 2$ at $z\simeq 1$, hosted by
halos with $\langle M \rangle \sim \mathcal{O}(10^{13}\,M_\odot)$. Repeating the analysis with a misaligned-AGN model yields consistent bias values, indicating that the result is determined by the clustering properties of the UGRB rather than by the details of the $\gamma$-ray source model.
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All authors Bhashin A. Thakore, Marco Regis, Michela Negro, Stefano Camera, Daniel Gruen, Nicolao Fornengo, Aaron J. Roodman
Solar and Stellar Astrophysics
The T-GEX project. II. Chrono-chemo-dynamic signatures of UV-bright FGK stars
D. Beltrán, M. L. L. Dantas, R. Smiljanic et al. (+1 more)
We compare the ages, chemical abundances, Galactic orbits, and inferred birth environments of 37 T-GEX
stars with strong (G1), normal (G2), and intermediate (G3) UV emission. The groups show distinct correlation structures: UV colours correlate with chemical and orbital quantities in G1; G2 has the largest number of significant (anti-)correlations; and no UV-colour correlation reaches the adopted threshold in G3. Most
stars have prograde disc-like orbits, while both
halo-like objects belong to G2. The groups overlap in the [Mg/Fe]-[Fe/H] plane, but G1 is shifted towards lower [Fe/H] and higher [Mg/Fe]. Among the 18 probable thin-disc members, G3 has a smaller median birth radius than G2 (5.70 versus 8.10 kpc), despite their nearly identical median guiding radii ($\langle R_g \rangle$; 8.23 versus 8.25 kpc). All five G1
stars are Ti-enriched compared to Fe, and four combine enhanced Co with comparatively low Mn and, in some cases, Cr. A related but less complete pattern occurs in G3, whereas Co enhancement in some G2
stars does not reproduce the joint signature. The UV-defined groups are heterogeneous and do not correspond to unique Galactic components. The convergence of $\alpha$-enhancement (likely thick disc members), positive Ti ratios, and the Cr-Mn-Fe-Co-Ni chemical abundance pattern (clearest in G1 but present in related form in G3) supports high-energy core-collapse (i.e. hypernovae) enrichment of the natal material of some UV-excess
stars. Additionally, the smaller G3 birth radii (for those in the Galactic thin disc) indicate more inward formation regions and provide a possible spatial link to UV-bright stellar populations in the bulges of spiral
galaxies. Neither result establishes a single causal pathway. Whether mixture-dependent metal-line blanketing connects this enrichment to the UV emission requires tailored spectral modelling.
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All authors D. Beltrán, M. L. L. Dantas, R. Smiljanic, P. B. Tissera
Cosmology and Nongalactic Astrophysics · Cross-listed from hep-ph
Collective flavor conversion in dense neutrino plasmas
Damiano F. G. Fiorillo
Compact transient sources, such as
supernovae (SNe) and
neutron star mergers (NSMs), host a population of thermal
neutrinos in their inner cores, which decouple from the dense matter as they stream out. Yet, collisionless does not mean free; their density is large enough to mediate collective waves driven by the coherent weak
neutrino–
neutrino interaction. These collective waves carry little energy, but crucially they transport flavor.
Neutrinos thus form a collisionless
plasma with flavor transport driven by flavor waves, whose quanta are called flavomons $\psi$. The wavelength of these flavomons is much shorter than the characteristic scales of SNe and NSMs, so that a brute-force numerical treatment of the
neutrino plasma is beyond our capabilities. Yet flavomons cannot be neglected, as the stimulated
neutrino decays, schematically $\overline{\nu}_e\to \overline{\nu}_\mu\psi$, cause a rapid buildup in their population, more conventionally called a flavor instability. We review the theory of the
neutrino plasma, and systematically discuss the instabilities leading to flavomon growth, and connect this emerging quasiparticle description with recent advances in numerical
neutrino flavor kinetics.
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Astrophysics of Galaxies
A High-Mass Size Deficit for Void Galaxies in the Complete SDSS DR7
Olivia Curtis, Bryanne McDonough and Tereasa G. Brainerd
We characterize how environment shapes the sizes, luminosity functions, and mass functions of
galaxies in large-scale underdensities by comparing the NSA catalog of the Sloan Digital Sky Survey Data Release 7 with an identically selected TNG300 sample, both built with the void finding
algorithm VoidFinder, and by assigning a local average underdensity contrast to each
galaxy via a spherical top-hat smoothed density field approximation. Void
galaxies have fainter characteristic magnitudes than their non-void counterparts, and, at fixed stellar mass,
redshift, and color, NSA void
galaxies with $M_*>10^{11}h^{-1}M_\odot$ are about $11\pm3\%$ more compact than
galaxies in the field, a deficit the TNG300 simulation reproduces. The
galaxies that are responsible for this effect are almost all central and predominantly early type, i.e., the systems that are most likely to grow their outer envelopes via late-time mergers. These trends hold across two
redshift bins to $z\leq0.114$. Crucially, this deficit is not a fixed property of the void sample but a steep function of the underdensity contrast, deepening toward the emptiest interiors and washing out at a typical density, implying that strict density control and sample selection are imperative when conducting environmental dependency studies like these. The same environmental dependence appears in the stellar mass function, which shifts to lower masses in the deepest voids, and in the close-pair (i.e., the ongoing merger) fraction, which falls toward the emptiest regions. Together, these point to a late-time, merger-driven growth of massive
galaxies that is suppressed in voids, leaving their most massive members structurally distinct today.
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Cosmology and Nongalactic Astrophysics · Cross-listed from hep-th
Cosmological Correlators from Scattering Amplitudes: A Review
Soner Albayrak and Savan Kharel
The primordial statistics underlying the CMB and large-scale structure are encoded in late-time cosmological correlation functions (constructed from the coefficients of the wavefunction of the universe). They are the closest analogue cosmology has to an $S$-
matrix, yet the standard $S$-
matrix toolkit does not directly apply. This review explains how the modern scattering-amplitudes program (spinor helicity, on-shell recursion, the double copy, positive geometry, and generalized unitarity) has nevertheless been extended to cosmology and, through a single analytic continuation, to Euclidean anti-de Sitter space, where the same objects appear as holographic boundary correlators and are often cleanest to compute. The organizing framework is momentum space on the late-time boundary, where the primordial statistics are simplest and where the total energy of the external legs, the sum of their momentum magnitudes, controls the analytic structure. At the total-energy singularity, the flat-space scattering amplitude emerges. We develop this toolkit starting from the wave equation and use it to compute tree-level scalar, gauge-field, and graviton correlators, exposing relations across
spins and dimensions. We then show how bulk integrals can be bypassed using cosmological polytopes, on-shell recursion, and curved-space versions of the double copy, before extending the discussion to loops, soft limits, transition amplitudes, and (A)dS cutting rules. Finally, we connect these structures to inflationary observables and to three allied programs: the cosmological optical
theorem, the cosmological bootstrap, and the cosmological
collider. We conclude with a map of the current frontier and a set of open and interesting problems.
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Earth and Planetary Astrophysics
Stellar companions sculpt hot Jupiter formation and spin-orbit evolution
Cheyanne Shariat, Kareem El-Badry, Songhu Wang et al. (+4 more)
Stellar companions can drive hot-Jupiter (HJ) migration and
spin-orbit misalignment, but their role in HJ formation remains uncertain. We construct a homogeneous census of resolved stellar companions to $147$ northern HJs with measured projected obliquities. We obtain uniform adaptive-optics imaging and combine these observations with Gaia common proper-motion pairs to identify 8 new companion candidates, bringing the observed companion fraction to $71/147=48\%$. Modeling the full survey selection function yields an intrinsic companion fraction of $62\pm5\%$ for mass ratios $q_\star=0.1$-$1$ and projected separations $s=50$-$50{,}000$~au, roughly 3-4$\times$ enhanced relative to field
stars. Including white-dwarf companions would increase this fraction further. HJs with resolved companions at $50$-$2{,}000$~au are nearly twice as likely to be misaligned compared to systems without detected companions: $46\%$ compared to $24\%$ ($p=0.009$). The misaligned fraction rises steadily from $5\%$ among the coolest hosts to $80\%$ among the hottest, without a sharp transition at the Kraft Break, while the intrinsic companion fraction remains roughly constant across the temperature range. These trends are consistent with HJs beginning with a broad obliquity distribution, followed by progressively weaker tidal realignment at higher stellar temperatures. Contrary to previous work, we find that most stellar companions in our sample are capable of driving eccentric Kozai-Lidov (EKL) oscillations to the tidal limit under suitable orbital configurations, making high-eccentricity migration dynamically promising. Taken together, these results indicate that stellar companions sculpt HJ formation and
spin–orbit architectures.
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All authors Cheyanne Shariat, Kareem El-Badry, Songhu Wang, Xian-Yu Wang, Malena Rice, Jerry W. Xuan, David R. Ciardi
Solar and Stellar Astrophysics
Precise and Accurate Mass and Radius Measurements of Thirty Galactic Metal-Poor Stars in Detached Eclipsing Binaries
D. M. Rowan, K. Z. Stanek, C. S. Kochanek et al. (+4 more)
Detached eclipsing binaries have long served as fundamental
benchmarks for making direct comparisons with stellar models. By combining the light curve and radial velocity orbit of a detached eclipsing binary, precise masses and radii can be measured for both components. However, catalogs of eclipsing binaries are dominated by solar-
metallicity stars. Here we characterize fifteen eclipsing binaries selected to have $[\rm{M/H}]\lesssim -0.5$ using TESS photometry, Gaia XP spectra, large spectroscopic surveys, and Galactic kinematics. We use three spectrographs, PEPSI on the Large Binocular
Telescope, the Levy spectrograph on the Automated
Planet Finder
telescope, and CHIRON on the SMARTS 1.5m
telescope. We jointly model the light curves and radial velocities and measure the stellar masses and radii with median fractional uncertainties of < 1%. We use spectral disentangling to extract the spectra of both
stars and model them using the spectral synthesis code Korg. We find three systems with $[\rm{M/H}] < -2.0$, two of which are kinematically consistent with the Milky Way's
halo. J0001+2156 has $[\rm{M/H}]=-2.51$, making it the most metal-poor detached eclipsing binary characterized to date. Eleven of the twelve other systems have $[\rm{M/H}] \lesssim -0.5$ and are split between being highly ($[\alpha/\rm{M}] > 0.25$) and moderately ($[\alpha/\rm{M}] < 0.25$) $\alpha$-enhanced. We compare our measured masses and radii to predictions from theoretical isochrones and estimate the ages of the binaries. We estimate ages with typical uncertainties of $\lesssim 0.5$ Gyr, and three of the binaries have estimated ages greater than 10 Gyr, up to $13.8^{+0.8}_{-0.7}$ Gyr. Finally, we update the empirical relations for stellar masses and radii on the main sequence using a sample of 621
stars.
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All authors D. M. Rowan, K. Z. Stanek, C. S. Kochanek, Benjamin J. Fulton, Ilya Ilyin, Howard Isaacson, David V. Martin
Astrophysics of Galaxies
Rubin LSST DP2 unveils almost-dark galaxies in the Virgo Cluster
Minh Ngoc Le, Johan H. Knapen, Željko Ivezić et al. (+26 more)
Galaxies with the faintest surface brightness are currently known only in the Local Group. Similar objects should exist beyond our vicinity and are crucial for understanding
galaxy evolution, structure, and dark matter content, yet surveys have not reached the depth required to detect them systematically. We present a population of seven almost-dark
galaxies identified in Data Preview 2 of the Rubin Legacy Survey of Space and Time. They surround M49 in the vicinity of the Virgo Cluster, and exhibit central surface brightnesses in the range of $26.9 - 28.5 \, \mathrm{mag \, arcsec^{-2}}$ in the $g$-band, with half-light radii of $0.6 - 4.6 \, \mathrm{kpc}$ at the distance of Virgo, and stellar masses of $10^6 - 10^7 \, \mathrm{M_\odot}$. Their characteristics are analogous to those of the faintest and low-mass
galaxies identified among satellite
galaxies And XXI, And XXIII, and And XXV in the Local Group. This discovery demonstrates the power of the forthcoming Rubin LSST 10-year survey to uncover extremely faint
galaxies at scale, promising the large statistical samples needed to constrain the faint-end luminosity function and the nature of dark matter.
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All authors Minh Ngoc Le, Johan H. Knapen, Željko Ivezić, Junais, Aaron Watkins, Dan S. Taranu, Pierre-Alain Duc, Anthony Englert, Erfan Nourbakhsh, J. Anthony Tyson, Jiaxuan Li, Roberto J. Assef, Uzay Aydin, Jose Benavides, Natanael M. Cardoso, Priyanka Chakraborty, Ricardo Demarco, Bililign Dullo, Alister W. Graham, Marc Huertas-Company, Kian-Tat Lim, Jakub Nadolny, Dieu Nguyen, Reynier Peletier, Rossella Ragusa, Kevin Reil, R. Michael Rich, Hector Hernandez-Toledo, Michael H. F. Wilkinson
Cosmology and Nongalactic Astrophysics
Where the Forest Goes Dark: Halo-centered Characterization of High Column Density Systems with IllustrisTNG
Victor R. Soares da Silva, Daniel López-Cano, L. Raul Abramo et al. (+2 more)
High column density systems of neutral hydrogen (HCDs) — Lyman limit systems (LLSs), sub-damped and damped Ly$\alpha$ absorbers (DLAs) — contaminate both the 3D and the 1D statistics of the Ly$\alpha$ forest. Most DLAs are masked out from the analyses, but cleaning
algorithms are not perfect, and weaker LLSs are individually undetectable, so the residual contamination is absorbed into nuisance parameters that dilute the cosmological constraining power. Simulations provide the ideal setting to study this effect, allowing absorption features to be directly traced back to the gas producing them. We identify high-column-density structures on the gas
cells of the TNG50 hydrodynamical simulation, deblend them in velocity space, and split every sightline into HCD-only and forest-only spectra. Applied to
halos at $z \simeq 3$ out to 50 virial radii, it yields each class's covering fraction against impact parameter $b$ and
halo mass. The impact parameter defines the type of absorption appearing in the spectrum: DLAs give way to sub-DLAs at $b \approx 0.11\,R_{200c}$, sub-DLAs to LLSs at $0.3$, and LLSs to the Ly$\alpha$-forest at $0.5$, which covers $\simeq 78\%$ of sightlines at $R_{200c}$. In units of $R_{200c}$ the sequence is nearly mass-independent over three decades in mass, so the virial radius sets the scale of the neutral gas distribution. A single Voigt component recovers the column density of essentially every damped system, but not of LLSs, whose absorption features often arise from several separate contributions from gas structures along the sightline. Our detailed characterization of HCDs gives the first step to the construction of advanced techniques to directly forward-model their contribution to Ly$\alpha$ spectra.
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All authors Victor R. Soares da Silva, Daniel López-Cano, L. Raul Abramo, J. Chaves-Montero, Francisco Maion
Earth and Planetary Astrophysics · Cross-listed from physics.geo-ph
Period-Inverted Blast-Radius Normalization for a Non-Ablating Hypersonic Reentry Source Using OSIRIS-REx Capsule Infrasound
Elizabeth A. Silber
Cylindrical blast wave theory relates infrasound from hypersonic sources to energy deposition through a characteristic blast radius R_0, yet the normalization constant k in the scaling R_0 = k (E_0/p_0)^(1/2) differs by up to 40% across the formulations examined here. This uncertainty affects period-based source characterization for elevated atmospheric sources relevant to infrasound monitoring. Using infrasound from the OSIRIS-REx Sample Return Capsule reentry on 24 September 2023, observed periods at 39 stations spanning source altitudes of 44-62 km are inverted through a weak-shock propagation model to obtain period-inverted blast radii R_0,obs without prescribing a blast-wave normalization. Combining R_0,obs with aerodynamic drag energy yields a median k = 0.396, with a modified-bootstrap 95% interval of 0.378-0.474 when the reported period-measurement uncertainties are included. This result is consistent with the Sakurai (1965) and Jones et al. (1968)/Plooster (1970) normalizations, while Few (1969) lies outside the reference confidence interval. However, station-level k values exhibit significant along-trajectory structure (Spearman r_s = -0.84, p < 0.001), indicating that k_med is an ensemble-effective normalization rather than a station-invariant constant. The Mach-diameter approximation R_0 ~ M d_m overestimates R_0 by a factor of ~3.4 for this effectively non-ablating source. A period-based relation, R_0 = 23.99 tau - 0.73 (R^2 = 0.991, MAPE = 2.3%), provides a rapid blast-radius
estimator whose residuals show no detectable altitude dependence. These results provide inverse calibration constraints and practical period-based source-characterization relations for OSIRIS-REx-like non-ablating hypersonic entries, while highlighting the need for multi-event validation before broader application.
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Earth and Planetary Astrophysics
A Binary Flux Calibrator Reveals the Scientific Potential of Short-integration JWST MIRI Imaging to Directly Detect sub-Jupiter Exoplanets
Rachel Bowens-Rubin, Mary Anne Limbach, Alexander Venner et al. (+11 more)
We report the direct imaging detection of a stellar companion to HD 101452 (HIP 56925; Gaia DR3 5384905720847544192), an A
star historically used as an infrared flux calibrator. The companion was identified from an asymmetry in the stellar PSF using short-integration (<1 min), noncoronagraphic JWST MIRI imaging from 15 - 25.5$\mu$m that was obtained as part of the absolute flux calibration program CAL 4496. We detect the stellar companion in four MIRI imaging filters at a projected separation of 1.3 arcsec with a mid-infrared flux ratio of approximately $27\times$ warranting its removal from the ensemble of JWST flux calibrator systems. This detection also demonstrates that noncoronagraphic MIRI imaging can recover companions at separations below $3\lambda/D$ when a reference
star with a closely matched flux level to the science target is available. Using the measured contrast curves from the calibration data, we evaluate the predicted sensitivity achievable with similar short MIRI observations for nearby
stars (<30 pc) that are of interest to the direct-imaging community with comparable brightness to HD 101452 (W4 ~ 6.8 mag). We find that integrations of only 17-42 s are be capable of detecting sub-Jupiter-mass
planets at solar system-like separations around a subset of neighboring systems if the PSF subtraction is conducted with closely flux-matched references. These results demonstrate that minutes-length, noncoronagraphic MIRI observations can provide a powerful and efficient new avenue for exploring the cold giant
planet population around nearby
stars.
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All authors Rachel Bowens-Rubin, Mary Anne Limbach, Alexander Venner, Kyle Franson, Emily K. Pass, Andrew Vanderburg, Kevin B. Stevenson, Logan Pearce, Taylor L. Tobin, Elisabeth Matthews, Aiza Kenzhebekova, Beth Biller, Ben J. Sutlieff, Klaus Subbotina Stephenson
Astrophysics of Galaxies
Massive Galaxy Halos Contain Less Inner Dark Matter Than Predicted
Yu-Chen Wang, Yingjie Peng, Xiaohu Yang et al. (+17 more)
The mass profiles of
galaxy halos encode how baryons reshape dark matter distribution, yet direct observational constraints across the full radial range remain scarce. Here we combine stellar kinematics from MaNGA, H I dynamical measurements from ALFALFA, and independently calibrated
halo masses of SDSS groups to statistically reconstruct the mass distribution of central
galaxies over nearly two orders of magnitude in radius. We demonstrate that H I data alone do not provide reliable total
halo mass estimates, necessitating an independent group-based
halo-mass scale. Compared to the IllustrisTNG and EAGLE simulations, the observational profiles of low-mass
halos are broadly consistent; in contrast, massive observed
halos exhibit systematically lower dynamical masses at the H I radius, lower inner dark-matter masses, and lower central dark-matter fractions (about 4$\sigma$ difference in units of population scatter) at fixed total
halo mass. After subtracting baryonic contributions, the inferred dark-matter profiles remain broadly consistent with an NFW form, but with lower effective concentrations than predicted for massive
halos. These results suggest that the inner dark-matter content of massive
halos has been reduced more significantly than predicted by current hydrodynamical simulations, plausibly due to long-term baryonic
halo heating in massive systems.
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All authors Yu-Chen Wang, Yingjie Peng, Xiaohu Yang, Luis C. Ho, Dingyi Zhao, Jing Dou, Hao Fu, Zeyu Gao, Qiusheng Gu, Fangzhou Jiang, Yukun Liu, Roberto Maiolino, Houjun Mo, Canpo Su, Bitao Wang, Kai Wang, Bingxiao Xu, Feng Yuan, Kunyao Zhao, Xingye Zhu
Earth and Planetary Astrophysics
An Updated Model for Epsilon Eridani b and Prospects for Imaging with the Roman Coronagraph
Jorge Llop-Sayson, Andre Fogal, James Mang et al. (+15 more)
Epsilon Eridani b, the nearest known Jupiter analog, has its orbit and mass constrained from radial velocity (RV) and absolute astrometry, and its atmosphere from JWST/NIRCam imaging upper limits in Sanghi et al. 2026. Here we follow up that work with a self-consistent model of Epsilon Eridani b that treats all available data within a single
Bayesian framework. We extend the RV data with new measurements, update the treatment of the astrometry data with a new model, and include the NIRCam observations with a grid of evolutionary and atmospheric models. We find a mass of 0.91+-0.06 M_Jup and an orbit consistent with previous work. The imaging data helps constrain
planet effective temperature, atmospheric
metallicity and surface
gravity. The constraints are dependent on model assumptions: for an atmosphere in chemical
equilibrium, an otherwise low statistically significant feature in one of the epochs is recovered as the
planet at high confidence. When assuming chemical disequilibrium, the posteriors exhibit a bimodal distribution, with one mode consistent with zero flux and the other coinciding with the flux of the tentative feature. Consistent with previous work, the clear atmosphere models are found to be viable at very enhanced
metallicity, whereas the cloudy models yield more moderate values. Applying these models to the Roman Coronagraph, we find that the predicted reflected-light fluxes place every cloudy atmosphere our fit allows within the instrument's expected sensitivity. A non-detection would be very constraining: a final contrast sensitivity of 2e-9 would rule out all cloudy atmospheres under our model assumptions.
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All authors Jorge Llop-Sayson, Andre Fogal, James Mang, William Thompson, Clarissa R. Do Ó, Aniket Sanghi, Isabela G. Huckabee, Laurent Pueyo, Charles Beichman, Geoffrey Bryden, Marie Ygouf, András Gáspár, Schuyler Wolff, Jarron Leisenring, Dimitri Mawet, Tiffany Meshkat, Caroline V. Morley, Jean-Baptiste Ruffio
High Energy Astrophysical Phenomena
Radiation-Driven Magnetic Fields in Sub-Keplerian Accretion Flows: An Alternative to MRI
Mukesh Kumar Vyas and Asaf Pe'er
Large scale
magnetic fields play a crucial role in shaping the dynamics and structure of the inner parts of
accretion disks and the resulting jets from the vicinity of black holes and
neutron stars. Currently, the primary mechanism considered for generating and amplifying large scale
magnetic fields in
accretion disks is the magneto-rotational instability (MRI). Here we show that non-conservative radiation fields provide a rapid and independent mechanism for generating and amplifying
magnetic fields in
accretion flows. A luminous, compact corona generates a radiation-driven poloidal field that is subsequently amplified by differential rotation, yielding quadratic
magnetic-field growth and, over a broad range of coronal luminosities and sizes and MRI amplification locations, magnetization on timescales comparable to or shorter than those of the MRI. The mechanism therefore provides not merely an alternative to MRI, but an additional and, over a substantial region of parameter space, dominant channel for
magnetic-field generation from initial conditions with zero
magnetic field. Since the radiation-driven source arises directly from the non-conservative nature of the radiation field, such
magnetic-field generation is an inevitable consequence of sufficiently strong and anisotropic radiation sources in black-hole
accretion flows. More generally, the mechanism requires only a non-conservative radiation field and differential
plasma motion, and is therefore expected to operate in a broad range of luminous astrophysical systems, including active galactic
nuclei, gamma-ray bursts, and tidal disruption events.
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Instrumentation and Methods for Astrophysics
Characterization of the CSST Survey Camera CCDs: I. basic electro-optical performance
Zun Luo, Hu Zhan, Youhua Xu et al. (+8 more)
The Chinese Space-station Survey
Telescope (CSST) is a flagship mission designed to carry out a large-area high-resolution multiband imaging and slitless spectroscopic survey over a decade. The survey's science drivers, ranging from precision cosmology to stellar astrophysics, impose stringent requirements on the performance of its focal plane detectors. This paper is the first in a series that present ground-based characterization of the 31 flight-model charge-coupled devices (CCDs) of the CSST Survey Camera. Measurements of basic electro-optical performance are reported here. Key results include: full-well capacity >80 ke (limited by the test electronics), non-linearity <1.4% in the range of 7-70 ke, median readout noise 3.6 e, dark current <0.02 e/pix/s at the operating temperature of -85 degree celsius, high
quantum efficiency across the survey's spectral range (255-1000 nm), typical pixel response non-uniformity <1%, and charge transfer efficiency >99.9994% at the flat-field level of 10 ke. All 31 CCDs meet or exceed the Survey Camera's specifications. These measurements establish a performance baseline and provide inputs for CSST image simulation and data processing pipelines
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All authors Zun Luo, Hu Zhan, Youhua Xu, Qiuyan Luo, Yuhe Song, Fajun Li, Li Shao, Zhe Huang, Haonan Chi, Huaipu Mu, Xiaolei Meng
Solar and Stellar Astrophysics
Oscillating dynamo models with a time-nonlocal $\alpha$ effect
Günther Rüdiger, Manfred Schultz and Alfio Bonanno
The traditional $\alpha$ effect is extended by the first temporal derivative, so that in turbulent flows the
magnetic field entering the induction process is effectively sampled in the past. As a consequence, dynamo excitation becomes easier and cycle times are prolonged relative to solutions obtained from the local standard formulation. The temporal shape of the
magnetic cycles is also modified, with rise times becoming shorter than decline times, so that the profiles acquire a characteristic “sawtooth” appearance. In the nonlocal formulation, the induced
magnetic-field amplitudes acquire an additional dependence on the correlation time. For fixed dynamo number, the field amplitude reaches a maximum at a certain correlation time. For correlation times larger than this peak value, the model can reproduce Waldmeier-type trends known from solar sunspot observations. If the actual correlation time fluctuates around this value, the long-term
magnetic cycle can occasionally enter weak-cycle episodes reminiscent of grand minima such as the Maunder minimum. For smaller dynamo numbers close to the critical one, however, rather long correlation times are required for this behaviour to occur.
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Cosmology and Nongalactic Astrophysics
Follow-up of SN 2025wny VI: The Rate and Detectable Population of Strongly Lensed SLSNe-I in ZTF
Jacob O. Hjortlund, Edvard Mörtsell, Ariel Goobar et al. (+13 more)
The Type I superluminous
supernova (SLSN-I) SN 2025wny, multiply imaged by two foreground
galaxies at $z_l = 0.375$, is the first confirmed strongly lensed SLSN and the highest-
redshift ($z_s = 2.015$) multiply imaged
supernova in a
galaxy-scale configuration. We ask whether one discovery in seven years of Zwicky Transient Facility (ZTF) operations is consistent with expectations, and whether SN 2025wny is typical of the detectable population. We develop a forward simulation of strongly lensed SLSNe-I in ZTF, combining an empirically calibrated volumetric rate and luminosity function with a
galaxy-scale deflector population, unresolved lensed light curves, and the actual ZTF observing history. We predict $0.037^{+0.022}_{-0.020}\,{\rm yr}^{-1}$, consistent with the rate of $0.14^{+0.31}_{-0.11}\,{\rm yr}^{-1}$ inferred from a single discovery in seven years of ZTF operations. Conditioning the simulation on discovery by ZTF corrects the magnifications and intrinsic luminosity of SN 2025wny for Malmquist- and magnification biases: the debiased peak bolometric luminosity, $\log_{10}(L_{\rm bol,int}/{\rm erg\,s^{-1}}) = 44.60^{+0.05}_{-0.10}$, places it at the $\sim$97th percentile of the assumed SLSNe-I luminosity function. SN 2025wny is typical of the detectable population in
redshift, luminosity, and magnification, but its $4.9''$ image separation exceeds single-
galaxy deflector expectations, implying our rates are conservative for wide-separation systems.
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All authors Jacob O. Hjortlund, Edvard Mörtsell, Ariel Goobar, Joel Johansson, Avinash Singh, Alice Townsend, Erin E. Hayes, Maggie L. Li, Steve Schulze, Suhail Dhawan, Jakob Nordin, Aleksandra Bochenek, Chiara Ventura, Conor M. B. Omand, Jacob L. Wise, Jesper Sollerman
Astrophysics of Galaxies
Rotational spectroscopy and astronomical search of propane-1-thiol (CH3CH2CH2SH) and propane-2-thiol ((CH3)2CHSH)
Wentao Song, Assimo Maris, Victor M. Rivilla et al. (+4 more)
This study focuses on propanethiol (or propyl mercaptan, C3H7SH), a sulfur analogue of propanol and a key target for investigating interstellar sulfur chemistry. We report the laboratory rotational spectroscopic characterization of its two structural isomers, propane-1-thiol (1PT) and propane-2-thiol (2PT). For 1PT, experimental analysis led to the observation of three almost isoenergetic conformers, Aa,Ag and Gg, marking the first-time report of the latter. For 2PT, both the anti and gauche conformers were identified. We also assigned, for the first time, several monosubstituted isotopologues in natural abundance: the 34S, 13C1, and 13C2 species for the anti-2PT conformer, as well as the 34S species for the gauche-2PT conformer.Resolvable tunneling splitting, caused by the large-amplitude motion of the sulfhydryl (SH) group, was observed for both the Ag-1PT and gauche-2PT conformers. Global fittings, integrating previous measurements, allowed for the accurate determination of rotational constants, quartic centrifugal distortion constants, and vibrational coupling parameters. The newly derived spectroscopic parameters were utilized to conduct an astronomical search toward the chemically rich Galactic Center molecular cloud G+0.693-0.027. While no evidence for propanethiol was found, we established rigorous upper limits for their column densities. These results indicate that 1PT and 2PT are approximately 13 and 5 times less abundant than ethanethiol in this source, respectively. Furthermore, the derived lower limit for the O/S ratio (29) for the 1-propanol/1-propanethiol pair is consistent with the solar value (37), proviiding a valuable
benchmark for understanding the depletion of sulfur in the ISM.
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All authors Wentao Song, Assimo Maris, Victor M. Rivilla, Miguel Sanz-Novo, Izaskun Jimenez-Serra, Luca Evangelisti, Sonia Melandri
Solar and Stellar Astrophysics
A large shell around the hypergiant VY Canis Majoris
D. P. K. Banerjee, V. Joshi, A. Evans A. A. Djupvik et al. (+10 more)
We report the detection of a remarkable shell around the red hypergiant VY CMa using data from the Spectro-Photometer for the History of the Universe, Epoch of Reionization, and Ices Explorer (SPHEREx). The shell, which in projection on the plane of the sky appears as a ring, is almost circular in appearance. It has an external diameter of $\sim14'$ to $15'$, and is seen most clearly in the SPHEREx 7827A spectro-photometric image. Filaments, radially aligned with VY CMa, are seen to cut across the shell in several places. We discuss the possibility that the shell is matter swept out from the neighboring
star forming region Sh 2-310, by the wind from VY CMa. Resonant atomic scattering, a light echo, or Extended Red Emission are explored as the source of the observed SPHEREx emission. However, no interpretation is without difficulty and further observations are most desirable.
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All authors D. P. K. Banerjee, V. Joshi, A. Evans A. A. Djupvik, Ken Hall, F.-J. Hambsch S. Sharma, G. Rangwal, A. Devaraj, T. R. Geballe, L. Izzo, T. Liimets, T. Schaeffer, S. Starrfield, C. E. Woodward
Solar and Stellar Astrophysics
Interferometric Survey of Stellar Parameters: Limb darkening study with the "Pipeline for Interferometric Measurements of Stars"
N. Ebrahimkutty, D. Mourard, P. Berio et al. (+21 more)
Accurate and unbiased determination of stellar parameters is of importance in many astrophysical domains. We therefore present an improved method to estimate stellar parameters, based on interferometric observations and stellar atmosphere models, as well as spectroscopic and photometric data. The fundamental stellar parameters were estimated by fitting a model of intensity profiles to interferometric data over a large spectral window and combining them with spectroscopic and photometric observations as an additional constraint on the fitting. Based on stellar atmosphere models, we have developed an
algorithm that trains artificial neural networks (ANNs) to estimate the spectrum and intensity profile of a
star over three bands: R, H, and K. The ANNs cover effective temperatures (Teff) ranging from 4500-7000 K for dwarf
stars and 2500-8000 K for giant
stars, with surface gravities (log g) ranging from 3.0-5.0 dex and -0.5-3.5 dex, respectively, and 12 viewing angles. As a result, consistent and precise stellar parameters, such as Teff, log g, and angular diameter ($\theta$), can be estimated. We fitted $\iota$ Psc (F7V) and $\delta$ Ari (G9.5IIIb) observed with SPICA, MIRC-X, and MYSTIC at the CHARA Array, and archival data of $\alpha$ Cen A and B (G2V and K1V) from VLTI/PIONIER with PIMS. For angular diameter estimations, when fitting with a one-dimensional stellar atmosphere model, we reached a precision of 0.5%. For Teff and radius, we obtained a precision of approximately 1%, while we obtained a precision of 5% for log g. Through evolutionary models, we further show how these constraints can improve the mass and age determination, as they attain a precision of approximately 2% for mass and 5-10% for age.
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All authors N. Ebrahimkutty, D. Mourard, P. Berio, O. Creevey, A. Domiciano de Souza, K. Lee, T. Morel, B. Plez, D. Salabert, N. Anugu, R. V. Ibañez Bustos, J. Jonák, H. Nowacki, M. Vrard, J. Dejonghe, F. Morand, N. Nardetto, A. Meilland, K. Perraut, M. Wittkowski, J. Monnier, S. Kraus, M. Gutierrez, N. Ibrahim
Astrophysics of Galaxies
CosmoDyn: a semi-analytic post-processing framework for the dynamical evolution of compact stellar systems and black holes in cosmological simulations
Pierre Boldrini, Paola Di Matteo, David Katz et al. (+5 more)
Although a large number of cosmological simulations are now publicly available, their spatial and mass resolutions remain insufficient to accurately follow the dynamics of compact stellar systems and black holes. A complementary approach is therefore required to exploit the cosmological assembly histories encoded in these simulations without rerunning them. We present CosmoDyn, an open-source Python framework that reconstructs time-dependent galactic environments from any cosmological simulations and explicitly follows unresolved compact objects within them. A distinctive feature of CosmoDyn is that it models not only the main host
galaxy but also its accreted satellites via moving gravitational potentials. The framework can therefore account simultaneously for the delivery of ex-situ populations and for the dynamical influence of satellites on in-situ population already present in the host. The modular pipeline comprises four main stages: reconstructing the evolving host and satellite potentials; generating in-situ and ex-situ populations of compact objects; integrating their orbits with configurable prescriptions for dynamical friction, and mass loss; and modeling tidal streams. Once reconstructed, the same cosmological environment can be reused to explore different objects, initial conditions, and physical prescriptions at low computational cost. CosmoDyn thus enables rapid parameter exploration and applications to statistically significant
galaxy samples, while its modular architecture is designed to incorporate progressively more realistic potentials, and formation models.
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All authors Pierre Boldrini, Paola Di Matteo, David Katz, Laia Casamiquela, Chervin Laporte, Maxime Assuerus, Marco Montuori, Glenn van de Ven
Solar and Stellar Astrophysics · Cross-listed from hep-ex
After 60 years, here comes the Sun
Anatael Cabrera, Mark Chen, Stefano Dusini et al. (+7 more)
For sixty years, the Sun served
neutrino physics more than the reverse: its
neutrinos established oscillations rather than probing the
star itself. That is now changing. Reactor antineutrinos have pinned down the oscillation parameters governing solar-
neutrino flavour conversion so precisely that the propagation-related uncertainty is becoming negligible – closing the first of two abysses. Solar
neutrinos can, at last, be turned on the Sun. Yet a second abyss remains: today's solar-
neutrino detection falls an order of magnitude short of the precision the Standard Solar Model already predicts for the dominant pp flux ($>\,$90$\%$) – a gap no reactor experiment can close. The intrinsic $^{14}\mathrm{C}$ background walls off the pp region; only new detection techniques can breach it. Bridging this second abyss demands a revolution, not an increment. Combined with helioseismology's complementary reading of the Sun's mechanical structure, precision
neutrino measurements of the nuclear source terms would enable a multi-messenger heliotomography of the solar interior – reading our
star from both sides at once. A new age of solar discoveries may follow, on one condition: that the field builds the instruments equal to the task.
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All authors Anatael Cabrera, Mark Chen, Stefano Dusini, Jeff Hartnell, Jorge Martín Camalich, Diana Navas Nicolás, Hiroshi Nunokawa, Aldo Serenelli, Javier Trujillo Bueno, Frédéric Yermia
Astrophysics of Galaxies
CNO in Giant Metal-Poor Stars
Jannat Alazzawi
We present the chemical abundance analysis for elements carbon, nitrogen, oxygen and the carbon isotopic ratio in a sample of metal-poor
stars selected from the RAVE survey based on their extreme radial velocities. Stellar parameters were derived using Gaia photometry and parallaxes, and elemental abundances were determined from high-resolution UVES spectra obtained at the ESO Very Large
Telescope. The
stars span a wide
metallicity range (-2.9 ___ [Fe/H] ___ -1.2) and, for the majority of the sample, exhibit kinematic properties consistent with the Galactic outer
halo population.
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High Energy Astrophysical Phenomena
Studying the Intermittency of Magnetized Interstellar Medium by Synchrotron Polarization Intensity and its Gradient
Ru-Yue Wang and Jian-Fu Zhang
Based on synthetic polarization observations, we qualitatively investigate the intermittency of the magnetized interstellar medium (ISM) through synchrotron polarization intensity (SPI) and synchrotron polarization gradient (SPG). Three principal findings emerge from our analysis: (1) The intermittency of the magnetized ISM is strongly modulated by magnetization and compressibility, with pronounced modulation effects predominantly observed in regimes characterized by strong magnetization and high compressibility. (2) The characterized intermittency of the magnetized ISM demonstrates a dependence on the electron spectral index under conditions where the random
magnetic field dominates. (3) SPG enables the identification of finer three-dimensional fractal structures in the case of strong Faraday depolarization. The synergistic application of SPI and SPG substantially enhances the reliability of probing magnetized ISM intermittency from real observations.
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Astrophysics of Galaxies
The Spitzer Data Fusion - A Far-Ultraviolet to Far-Infrared Multi-Wavelength Database in Spitzer Extragalactic Survey Fields
Mattia Vaccari
I present the Spitzer Data Fusion, a multi-wavelength photometric database providing far-ultraviolet to far-infrared flux measurements, together with photometric and spectroscopic
redshifts, for 4.4 million IRAC-selected sources over 65\,deg$^2$ in eight of the most widely studied extragalactic survey fields. A companion product, the SERVS Data Fusion, provides 2.8 million sources over 18\,deg$^2$ selected from deeper Spitzer warm-mission imaging. Catalogs are band-merged with wavelength-dependent matching radii, astrometrically registered against 2MASS, and distributed as FITS binary tables, one per field, as \href{https://doi.org/10.5281/zenodo.6120913}{DOI: 10.5281/zenodo.6120913} and as CDS/VizieR \href{https://cdsarc.cds.unistra.fr/viz-bin/cat/II/377}{catalog II/377}. The database is intended as a community resource for photometric
redshift calibration, spectral energy distribution fitting, sample selection and multi-wavelength cross-identification, and is a natural bridge between the Spitzer legacy fields and ongoing Euclid, Rubin and SKA precursor surveys.
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Instrumentation and Methods for Astrophysics
The Nancy Grace Roman Space Telescope Coronagraph Community Participation Program
Dmitry Savransky, Vanessa P. Bailey, Schuyler G. Wolff et al. (+53 more)
In preparation for the operational phase of the Nancy Grace Roman Space
Telescope, NASA has created the Coronagraph Community Participation Program (CPP) to prepare for and execute Coronagraph Instrument technology demonstration observations. The CPP is composed of 7 small, US-based teams, selected competitively via the Nancy Grace Roman Space
Telescope Research and Support Participation Opportunity, members of the Roman Project Team, and international partner teams from ESA, JAXA, CNES, and the Max Planck Institute for Astronomy. The primary goals of the CPP are to prepare simulation tools, target databases, and data reduction software for the execution of the Coronagraph Instrument observation phase. Here, we present the current status of the CPP and its working groups, along with plans for future CPP activities up through Roman's launch. We also discuss plans to potentially enable future commissioning of currently-unsupported modes.
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All authors Dmitry Savransky, Vanessa P. Bailey, Schuyler G. Wolff, Maxwell A. Millar-Blanchaer, Jason Wang, Lisa Altinier, Ramya Anche. Pierre Baudoz, Beth Biller, Sarah Blunt, Wolfgang Brandner, Marah Brinjikji, Oscar Carrión-González, Amanda Chavez, Elodie Choquet, David Doelman, Julien H. Girard, Alexandra Z. Greenbaum, Samantha N. Hasler. Justin Hom, James G. Ingalls, Stephen R. Kane, N. Jeremy Kasdin, Oliver Krause, Masayuki Kuzuhara, Alexis Lau, Zhexing Li, John Livingston, Patrick J. Lowrance, Kevin Ludwick, Bruce Macintosh, Eric Mamajek, Mark Marley, Johan Mazoyer, Bertrand Mennesson, Toshiyuki Mizuki, Sarah E. Moran, Naoshi Murakami, Jun Nishikawa, Malachi Noel, Laurent Pueyo, Sergi Hildebrandt Rafels, Jason Rhodes, Tyler Robinson, Robert J. De Rosa, Matthias Samland, Nicholas Schragal, Jürgen Schreiber, Jennifer Sobeck, Karl Stapelfeldt, Motohide Tamura, Taichi Uyajma, Arthur Vigan, Michele Woodland, Marie Ygouf, Kenta Yoneta, Robert T. Zellem, Neil T. Zimmerman
Solar and Stellar Astrophysics
A homogeneous analysis of archival and new low-resolution spectra of YZ Cancri
Zhibin Dai, Lihuan Yu, Jiao Li et al. (+2 more)
YZ Cancri is an SU UMa-type dwarf nova with sparse and heterogeneous optical spectroscopy. We present a homogeneous analysis of archival outburst-related spectra and seven new low-resolution quiescent spectra. We consistently characterize the Balmer, He I, Fe II, O I, and occasional He II and Bowen features, and assess which state-dependent differences are robustly supported. We applied a common continuum-normalization and line-measurement procedure, measuring equivalent widths, integrated line intensities, and selected profile parameters, and comparing line morphologies and intensity ratios between quiescent and outburst-related states. Because the spectra have modest and nonuniform resolving power and are not orbital-phase resolved, profile widths and centroid shifts are used only as relative diagnostics. Outburst-related spectra are dominated by broad Balmer absorption or composite profiles, whereas quiescent spectra show strong single-peaked Balmer and He I emission, recurrent Fe II {\lambda}5169, and weak O I {\lambda}7772 emission. He II {\lambda}4686 is detected in only two quiescent exposures, and the Bowen blend in one. The quiescent Balmer decrement is relatively flat, while the He I ratios show substantial exposure-to-exposure scatter. The measured Fe II ratios show no clear systematic departure from optically thin reference values, although blending limits their interpretation. These spectra establish an empirical state-dependent description of YZ Cnc and provide a reference
dataset for future phase-resolved, higher-resolution spectroscopy.
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All authors Zhibin Dai, Lihuan Yu, Jiao Li, Xuefei Chen, Zhanwen Han
Solar and Stellar Astrophysics
The emergence of a [WC] star in Sakurai's object
W. Marcolino, P. A. M. van Hoof, V. C. Maria et al. (+9 more)
Sakurai's object provides a rare opportunity to observe stellar
evolution on human timescales. Since its born-again event and detection in 1996, its
evolution has been extensively monitored, and recent optical spectroscopy has suggested the emergence of [WR]-type emission features. In this Letter, we present a secure spectroscopic identification of its central
star based on new VLT/FORS2 observations and NLTE expanding atmosphere models. Several observed emission lines arise in a [WR]-type stellar wind, establishing the central
star as a [WR] object. The strongest stellar features are due to C II-III and He I. We derive the stellar and wind parameters of Sakurai's object and discuss its evolutionary status. The [WR]
star is much cooler (Teff ~ 30.5 kK) than the born-again
star V605 Aql (Teff} ~ 95 kK), which erupted about 80 years earlier. The inferred temperature is lower than predicted by models suppressing convective mixing efficiency during the VLTP, but is consistent with higher time-resolution calculations involving slightly lower-mass (<~ 0.6Msun) remnants. Continued spectroscopic monitoring and atmospheric modelling will be crucial for tracing its reheating curve and constraining the physics of this rapid evolutionary phase.
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All authors W. Marcolino, P. A. M. van Hoof, V. C. Maria, H. Todt, G. C. Van de Steene, J. A. Toalá, S. Kimeswenger, M. Hajduk, J.-C. Bouret, D. Tafoya, D. Barría, A. A. Zijlstra