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Physics Astrophysics

astro-ph Watch Astrophysics

Friday 5 December

Cosmology and Nongalactic Astrophysics

The Glow of Axion Quark Nugget Dark Matter: (IV) CMB Spectral and Anisotropy Signatures

Fereshteh Majidi, Xunyu Liang, Michael Sekatchev et al. (+2 more)

Axion quark nuggets (AQNs) are macroscopic dark-matter candidates, with masses of the order of a few grams to a kilogram and sub-micron radius, thought to form at the Quantum Chromo Dynamic era through axion-induced charge separation. This framework naturally links the dark and visible matter abundances ($\Omega_{\rm DM} \sim \Omega_{\rm visible}$) and provides a mechanism for generating the baryon-antibaryon asymmetry where dark matter is composed of matter AQNs and antimatter AQNs. Although behaving as cold dark matter on cosmological scales, baryons annihilate with antimatter AQNs, producing ionizing high-energy photons. The resulting energy injection may imprint spectral distortions on the cosmic microwave background (CMB) and modify the reionization history. Using a modified version of the CLASS Boltzmann code we compute the impact of this energy injection on the $\mu$ and $y$ spectral distortion parameters as well as on the optical depth. We find that (1) the CMB anisotropies remain essentially unaffected by baryon annihilation, and (2) the associated spectral distortion signatures lie within the sensitivity reach of proposed CMB spectral distortion missions. Finally, we discuss the similarities and differences between the AQN scenario and annihilating or decaying dark matter models.
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All authors Fereshteh Majidi, Xunyu Liang, Michael Sekatchev, Ludovic Van Waerbeke, Ariel Zhitnitsky

Cosmology and Nongalactic Astrophysics · Cross-listed from hep-ph

Illuminating sequential freeze-in dark matter with dark photon signal at the CERN SHiP experiment

Xinyue Yin and Sibo Zheng

Single-field freeze-in dark matter barely leaves observable footprints in dark matter direct detection, collider or fixed-target experiments, which can be altered in the two-field context. In this work, we consider sequential freeze-in dark matter through signals of dark photon mediator with a mass range of $m_{A'}\sim 10^{-2}-10$ GeV covered by the proposed SHiP experiment. We show that the dark charge is fixed to be $e'\sim 1.3\times 10^{-12}$ and the mixing parameter is restricted to $10^{-11}\leq \epsilon< 10^{-8}-10^{-7.5}$, as a result of the out-of-equilibrium condition of dark photon and the observed relic abundance of dark matter. Within this $\epsilon$ region, the 5(15)-year data of proton bremsstrahlung process for the dark photon, assuming vector meson (dipole) dominance, excludes $\epsilon\geq 10^{-8.5} (10^{-7.9})$ at 90% confidence level, implying only a narrow region of $\epsilon$ close to $\sim 10^{-11}$ left for alternative tests.
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Earth and Planetary Astrophysics

On-Orbit Calibration of Danuri/PolCam. I. Geometric Calibration

Kilho Baek, Sungsoo S. Kim, Minsup Jeong et al. (+1 more)

The wide-angle Polarimetric Camera (PolCam) onboard South Korea's first lunar orbiter, Danuri, is a pioneering instrument designed to conduct the first global polarimetric and high-phase-angle survey of the Moon. Precise geometric calibration is critical for this mission, particularly due to PolCam's highly oblique viewing geometry, which introduces significant topographic distortion. We present a comprehensive on-orbit geometric calibration that relies on 160,256 tie points derived from matching features between PolCam images and the well-orthorectified global map of the Kaguya Multiband Imager (MI). This dataset allows us to address two fundamental challenges: (1) the accurate reconstruction of the observation time for each line of an observation strip via a simple linear model, and (2) the refinement of the precise camera model, geometric model for PolCam optics. Our optimization method for these two challenges transforms the 2D image coordinates of identified features into 3D lunar coordinates and minimizes the reprojection error against the reference coordinates provided by the Kaguya MI map. From the refined observation time and camera model, we compute the precise longitude, latitude, and elevation of each pixel of an observed image. These estimated 3D coordinates are then used to generate orthorectified images, the final product of the geometric calibration. The resulting calibration achieves a geometric precision comparable to that of previous lunar orbiters and establishes the foundational framework necessary to produce geometrically-corrected data products of PolCam.
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All authors Kilho Baek, Sungsoo S. Kim, Minsup Jeong, Young-Jun Choi

Thursday 4 December

Instrumentation and Methods for Astrophysics

SATMO: a Multi-Planet Thermal Analysis Tool for CubeSat Missions

Alexander Chipps, Daniel Forgette and Kerri Cahoy

The expansion of commercial launch capabilities has significantly increased opportunities for interplanetary small satellite (SmallSat) missions. As researchers plan for more missions beyond Earth, there is a demand for accessible tools that help better predict and understand the thermal effects on their spacecraft in orbital environments around Earth and other bodies. While commercial thermal analysis tools offer high-fidelity modeling capabilities and results, they are often expensive and require extensive training to be used effectively. This paper details a framework for a user-friendly Satellite Thermal Model (SATMO) to support the early stages of space mission planning for CubeSats orbiting Earth and other Solar System bodies. SATMO is an open-source, MATLAB-based, six-node thermal analysis program designed for satellites in low-altitude circular orbits. Although SATMO requires a MATLAB license – typically inexpensive or institutionally provided in academic settings – it remains substantially more accessible than professional thermal analysis software. SATMO requires an internet connection for some features but does not rely on additional MATLAB toolboxes. The SATMO modeling approach is validated with the space industry standard Thermal Desktop software, with temperatures comparable to within 1.17$^\circ$C for a 10 cm $\times$ 10 cm $\times$ 10 cm CubeSat in various configurations, orbiting around primary bodies including Earth, Venus, and Mars. An example use case of SATMO is presented with a Mars-orbiting CubeSat to demonstrate its functionalities and the outputs available to users. SATMO offers increased accessibility to satellite thermal modeling for the research community, enabling quick thermal trade studies and interplanetary mission plans.
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Earth and Planetary Astrophysics

Searching for Transit Timing Variations in young transiting systems

Ana Isabel Lopez Murillo, Andrew W. Mann, Madyson G. Barber et al. (+3 more)

The discovery of young (<800 Myr) transiting planets has provided a new avenue to explore how planets form and evolve over their lifetimes. Mass measurements for these planets would be invaluable, but radial velocity surveys of young systems are often overwhelmed by stellar activity. Transit timing variations (TTVs) offer an alternative route to measure masses that are less impacted by signals from the host star. Here we search for candidate TTVs in a sample of 39 young systems hosting 53 transiting planets using data from Kepler, K2, and TESS. We recover previously reported TTVs for 11 planets, including those in V1298 Tau, TOI-2076, Kepler-51, and TOI-1227, and identify new candidate TTVs for four planets (DS Tuc Ab, HD 63433b, K2-101b, and Kepler-1643b). In total, 28.3 +/- 6.2% of young planets in our sample show evidence of TTVs, which is higher than the rate from Kepler on mostly older systems (7.3 +/- 0.6%). Accounting for differences in data coverage and quality between Kepler and TESS only increases this difference (> 4$\sigma$), although differences in methodology make a totally fair comparison challenging. We show that spots have a weak-to-negligible impact on our results, and similarly cannot explain the higher TTV fraction. Longer-term monitoring will be required to validate these TTVs as planetary in nature and confirm the high TTV rate. While the candidate TTV signals detected here are sparsely sampled, our work provides a clear priority list for additional ground-based observations, and for multi-planet TTVs, attempt to measure the masses and eccentricities of these planets.
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All authors Ana Isabel Lopez Murillo, Andrew W. Mann, Madyson G. Barber, Andrew Vanderburg, Pa Chia Thao, Andrew W. Boyle

High Energy Astrophysical Phenomena

Nuclear parameter inference with semi-agnostic priors

Lami Suleiman, Anthea F. Fantina, Francesca Gulminelli et al. (+1 more)

Radio pulsar timing, X-ray pulse profile modeling, and gravitational-wave detections of binary mergers involving at least one neutron star probe the properties of dense, neutron-rich matter in thermodynamic regimes inaccessible to nuclear laboratories. Such inference relies on building appropriate equation-of-state priors, such as the recently introduced semi-agnostic constructions that incorporate nuclear theory and experimental information available in low- to intermediate-density regimes, while offering the necessary flexibility at high density. In this paper, we assess how detections of mass, radius, and tidal deformability for low-mass or high-mass neutron stars contribute to constraining nuclear empirical parameters in an inference based on semi-agnostic equation-of-state priors. We first assessed the correlation factors between nuclear empirical parameters and the zero-temperature and beta-equilibrated pressure in different density regimes. We then simulated observations for three nucleonic equations of state to test the recovery of the corresponding nuclear empirical parameters. We show that not all nuclear empirical parameters significantly correlate with the pressure and find that they compete in the high-density regime, which challenges their inference. We also find that using semi-agnostic constructions instead of assuming a nucleonic content up to the highest densities in the neutron-star core can help recover the true nuclear empirical parameters with more accuracy. Parametrizing the high-density regime of the equation of state with the nucleonic meta-model can bias the inference of nuclear empirical parameters; semi-agnostic constructions provide a solution to this problem. However, many nuclear parameters contribute similarly to the construction of the baryonic pressure. We find that they are difficult to infer independently, even with extremely precise measurements.
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All authors Lami Suleiman, Anthea F. Fantina, Francesca Gulminelli, Jocelyn Read

High Energy Astrophysical Phenomena

Absorption of strong electromagnetic waves in magnetized pair plasmas

Emanuele Sobacchi

We discuss synchrotron absorption of a short electromagnetic pulse that propagates in a cold magnetized pair plasma. We show that the pulse can be absorbed when $\omega_{\rm B}/a_0< \omega< a_0\omega_{\rm B}$, where $a_0>1$ is the strength parameter of the pulse, and $\omega$ and $\omega_{\rm B}$ respectively are the frequency of the wave and the cyclotron frequency in the background magnetic field (all quantities are defined in the reference frame where the particles are at rest before being illuminated by the pulse). The condition $\omega_{\rm B}/a_0< \omega< a_0\omega_{\rm B}$ is essentially a generalization of the cyclotron resonance to strong electromagnetic pulses with $a_0>1$. When $\omega_{\rm B}/a_0< \omega< a_0\omega_{\rm B}$, the propagation of electromagnetic waves in a plasma can be very different with respect to the propagation in vacuum because the wave equation is strongly non-linear. Then it is unclear whether the particles are heated stochastically due to synchrotron absorption, as found by studying the motion of a test particle in the field of a vacuum electromagnetic wave. We discuss implications of our results for constraining emission models of fast radio bursts.
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Earth and Planetary Astrophysics

Multi-bandpass Photometry for Exoplanet Atmosphere Reconnaissance (MPEAR) with the Habitable Worlds Observatory (HWO) – I. Differentiating Earth from Neptunes During Discovery

Eleonora Alei, Avi M. Mandell, Miles H. Currie et al. (+7 more)

As the architecture for the Habitable Worlds Observatory (HWO) is being developed, it is crucial to optimize the observing strategies for a survey to detect and characterize Earth-like planets around Sun-like stars. Efficient target identification and characterization will help drive mission requirements that can be matched to the planned observations. Current HWO concepts allow simultaneous multi-bandpass observations with the coronagraph instrument, critical for performing a qualitative planetary reconnaissance to optimize observing time for deriving orbital constraints and prioritize characterization of promising targets. We describe a new algorithm designed to determine the best combination of broadband photometric observations for extracting maximum information from the first visit. It identifies degeneracies in the orbital configurations, fluxes, and noise, and determines optimal secondary photometry bands to reduce these. We demonstrate its application by comparing an Earth seen at quadrature with a cold and a warm Neptune at inclined orbits and varying phases, with comparable flux in the discovery bandpass centered at 500 nm (20% bandwidth). Using the noise and exposure time calculator that we developed for the HWO coronagraph instrument, we find that the baseline $S/N=7$ (corresponding to 3.2 hours observing time for a planet at 10pc) is only sufficient to marginally differentiate the Earth from a cold Neptune-like planet assuming two parallel bandpasses (550 nm + 850 nm). However, increasing to $S/N=15$ (7 hours observing time) and using three parallel bandpasses (360 nm + 500 nm + 1.11 micron) would differentiate the Earth from either a warm or cold Neptune.
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All authors Eleonora Alei, Avi M. Mandell, Miles H. Currie, Aki Roberge, Christopher C. Stark, Allison Payne, Vincent Kofman, Geronimo L. Villanueva, Renyu Hu, Amber V. Young

High Energy Astrophysical Phenomena

Multiple outflows and delayed ejections revealed by early imaging of novae

Elias Aydi, John D. Monnier, Antoine Mérand et al. (+39 more)

Novae are thermonuclear eruptions on accreting white dwarfs in interacting binaries. Although most of the accreted envelope is expelled, the mechanism – impulsive ejection, multiple outflows or prolonged winds, or a common-envelope interaction – remains uncertain. GeV $\gamma$-ray detections from $>20$ Galactic novae establish these eruptions as nearby laboratories for shock physics and particle acceleration, underscoring the need to determine how novae eject their envelopes. Here we report on near-infrared interferometry, supported with multiwavelength observations, of two $\gamma$-ray detected novae. The images of the very fast 2021 nova V1674~Her, taken just 2–3 days after discovery, reveal the presence of two perpendicular outflows. The interaction between these outflows likely drives the observed $\gamma$-ray emission. Conversely, the images of the very slow 2021 nova V1405~Cas suggest a delay in the ejection of the bulk of the accreted envelope of more than 50 days after the start of eruption, as the nova slowly rises to visible peak and during which the envelope engulfed the system in a common envelope phase. These unprecedented images offer direct observational evidence that the mechanisms driving mass ejection from the surfaces of accreting white dwarfs are not as simple as previously thought, revealing multiple outflows and delayed ejections.
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All authors Elias Aydi, John D. Monnier, Antoine Mérand, Gail H. Schaefer, Laura Chomiuk, Magdalena Otulakowska-Hypka, Jhih-Ling Fan, Kwan Lok Li, Kirill V. Sokolovsky, Ricardo Salinas, Michael Tucker, Benjamin Shappee, Richard Rudy, Kim L. Page, N. Paul M. Kuin, David A. H. Buckley, Peter Craig, Luca Izzo, Justin Linford, Brian D. Metzger, Koji Mukai, Marina Orio, Ken J. Shen, Jay Strader, Jennifer L. Sokoloski, Robert E. Williams, Montana N. Williams, Gesesew R. Habtie, Stefan Kraus, Narsireddy Anugu, Jean-Baptiste Le Bouquin, Sorabh Chhabra, Isabelle Codron, Tyler Gardner, Mayra Gutierrez, Noura Ibrahim, Cyprien Lanthermann, Benjamin R. Setterholm, Christopher Ashall, Jason T. Hinkle, Thomas de Jaeger, Anna V. Payne

High Energy Astrophysical Phenomena

Two Step Localization Method for Electromagnetic Followup of LIGO-Virgo-KAGRA Gravitational-Wave Triggers

Daniel Skorohod and Ofek Birnholtz

Rapid detection and follow-up of electromagnetic (EM) counterparts to gravitational wave (GW) signals from binary neutron star (BNS) mergers are essential for constraining source properties and probing the physics of relativistic transients. Observational strategies for these early EM searches are therefore critical, yet current practice remains suboptimal, motivating improved, coordination-aware approaches. We propose and evaluate the Two-Step Localization strategy, a coordinated observational protocol in which one wide-field auxiliary telescope and one narrow-field main telescope monitor the evolving GW sky localization in real time. The auxiliary telescope, by virtue of its large field of view, has a higher probability of detecting early EM emission. Upon registering a candidate signal, it triggers the main telescope to slew to the inferred location for prompt, high-resolution follow-up. We assess the performance of Two-Step Localization using large-scale simulations that incorporate dynamic sky-map updates, realistic telescope parameters, and signal-to-noise ratio (SNR)-weighted localization contours. For context, we compare Two-Step Localization to two benchmark strategies lacking coordination. Our results demonstrate that Two-Step Localization significantly reduces the median detection latency, highlighting the effectiveness of targeted cooperation in the early-time discovery of EM counterparts. Our results point to the most impactful next step: next-generation faster telescopes that deliver drastically higher slew rates and shorter scan times, reducing the number of required tiles; a deeper, truly wide-field auxiliary improves coverage more than simply adding more telescopes.
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Astrophysics of Galaxies

GA-NIFS: A smouldering disk galaxy undergoing ordered rotation at z=4.26

Gareth C. Jones, Roberto Maiolino, Francesco D'Eugenio et al. (+13 more)

Rotating galaxies with relaxed gaseous disks have been discovered across cosmic time, from the local Universe to high redshift (z>4). But few such sources have been confirmed at z>4, making them a precious sample to examine what conditions result in such ordered kinematics in an early, more chaotic Universe. One of the best examples of this sample is the galaxy DLA0817g1 (z=4.2603), which shows remarkably clear rotation in ALMA [CII] data. We present recent JWST/NIRSpec IFU data (R~2700) of DLA0817g1, which we combine with archival ALMA [CII] observations to place constraints on its ISM conditions and morpho-kinematics. From a combination of line ratios, we find a high gas-phase metallicity (~0.7 solar), high fraction of obscured star formation, low ionisation (compared to other high-redshift galaxies observed with JWST), and no significant evidence for AGN (based on the WHAN diagnostic). Dynamical modelling with 3DBarolo reveal nearly identical rotation in Halpha and [CII], but with a higher velocity dispersion in the former. Using our metallicity estimate and previous CO and [CII] detections, we derive a new estimate of the molecular gas mass, relieving a previous strain in the mass budget. Altogether, we suggest that this is a 'smouldering' galaxy, where past star formation resulted in significant chemical enrichment (i.e., Zgas and Mdust), but the current activity is low (i.e., lower ionisation parameter and electron temperature). These new observations have opened a window into questions regarding the interplay of gas, metallicity, star formation, and kinematics in a prototypical early disk galaxy.
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All authors Gareth C. Jones, Roberto Maiolino, Francesco D'Eugenio, Santiago Arribas, Andrew J. Bunker, Stephane Charlot, Michele Perna, Bruno Rodriguez del Pino, Hannah Übler, Torsten Böker, Giovanni Cresci, Isabella Lamperti, Eleonora Parlanti, Robert Pascalau, Jan Scholtz, Sandra Zamora

High Energy Astrophysical Phenomena

Lagrangian versus Eulerian Methods for Toroidally-Magnetized Isothermal Disks

Yashvardhan Tomar and Philip F. Hopkins

A number of simulations have seen the emergence of strongly-toroidally-magnetized accretion disks from interstellar medium inflows. Recently, Guo et al. 2025 (G25) studied an idealized test problem of toroidally-magnetized disks in isothermal ideal MHD with an Eulerian static-mesh method, and argued the midplane behavior changes qualitatively (with a significant loss of toroidal magnetic flux) when the the thermal scale-length is resolved ($\Delta x < H_{\rm thermal}$). We rerun the G25 test problem with two Lagrangian methods: meshless finite-mass, and meshless finite-volume. We show that Lagrangian methods reproduce the high-resolution ($\Delta x \ll H_{\rm thermal}$) Eulerian G25 results. At low resolution ($\Delta x \gg H_{\rm thermal}$), behaviors differ: Lagrangian methods still lose flux and evolve 'as close as possible' to the converged solution, while Eulerian methods show no evolution. We argue this difference in convergence behavior is related to the ability of Lagrangian codes to follow flows to an arbitrarily thin midplane layer, analogous to the well-studied difference in Jeans fragmentation problems. This and results from other higher-resolution simulations and different codes suggest that the sustained midplane toroidal fields seen in recent Lagrangian multi-scale, multi-physics simulations cannot be a numerical resolution effect, and some physical difference between those simulations and the G25 test problem explains their different behaviors.
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High Energy Astrophysical Phenomena · Cross-listed from gr-qc

Black-hole ringdown with templates capturing spin precession: A reanalysis of GW190521

Chiara Anselmo, Costantino Pacilio and Davide Gerosa

The ringdown stage of a binary black-hole merger provides a clean probe of strong-field gravity, as it can be modeled with minimal assumptions. The quasi-normal-mode frequencies encode the mass and spin of the Kerr black hole remnant, while the mode excitation depends on the progenitor binary. In this paper, we implement a recently developed amplitude model that captures spin precession in a simulation-based inference pipeline that specifically targets ringdown signals. We present a reanalysis of GW190521-a short-duration, merger-dominated event with conflicting interpretations. Spin-aligned and precessing analyses at two ringdown start times show that precession induces modest but systematic shifts in inferred parameters and subdominant mode amplitudes, although such ringdown-only analyses provide no strong evidence for precession. Our results demonstrate the feasibility of physics-informed precessing ringdown modeling, paving the way for the identification of spin precession in gravitational-wave events using solely their ringdown stages, where waveform systematics are expected to be substantially less prominent.
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Earth and Planetary Astrophysics

Keck Observations in the INfrared of Taurus and $\rho$ Oph Exoplanets And Ultracool dwarfs (KOINTREAU) I: A Planetary-Mass Companion and a Disk-Obscured Stellar Companion Discovered in Taurus

Samuel A. U. Walker, Michael C. Liu, Dimitri Mawet et al. (+10 more)

We present the first discoveries from Keck Observations in the INfrared of Taurus and $\rho$ Oph Exoplanets And Ultracool dwarfs (KOINTREAU), an adaptive optics imaging survey of young stars in the Taurus and $\rho$ Oph star-forming regions using the Keck infrared pyramid wavefront sensor (PyWFS). We have found two faint ($\Delta$K~7 mag), wide-separation companions to two ~3-Myr-old Taurus members. Relative astrometry for these systems show that both companions are bound to their host stars. We obtained near-infrared spectra of these companions using IRTF/SpeX (R~100) and Gemini/GNIRS (R~1000-2000), and combine these with photometry from our NIRC2 imaging, the Pan-STARRS survey, and Spitzer/IRAC archival imaging to constrain their properties. One companion, KOINTREAU-1b (at a projected separation of 690 au), has an average near-IR spectral type of M9$\pm$2, a gravity classification of VL-G, and a changing spectral type between the SpeX (M7) and GNIRS (L1) observations. We estimate this object's mass to be $10.6^{+2.5}_{-2.3}$ M$_{\rm Jup}$, making KOINTREAU-1b the fifth planetary-mass companion found in Taurus. The other companion, KOINTREAU-2b (projected separation 560 au), has a spectral type of M4.5$\pm$1 but is ~4 magnitudes underluminous relative to other Taurus stars of the same spectral type. We detect exceptionally strong He I 1.083 micron emission from this object, indicative of outflows driven by ongoing accretion, but with a conspicuous lack of accompanying H emission. We conclude that KOINTREAU-2b is a young star obscured by an edge-on disk and observed in scattered light. Finally, we derive a distortion solution for NIRC2 imaging which shows a 0.118{\deg} difference in position angle from the previous distortion solution.
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All authors Samuel A. U. Walker, Michael C. Liu, Dimitri Mawet, Charlotte Bond, Mark Chun, Raquel A. Martinez, Mark W. Phillips, Jonathan P. Williams, Zhoujian Zhang, Bin B. Ren, Karl Stapelfeldt, Taichi Uyama, Nicole Wallack

Cosmology and Nongalactic Astrophysics · Cross-listed from hep-ph

Thermal Damping of Mass-Modulating Scalars

Abhishek Banerjee, Ngan H. Nguyen and Erwin H. Tanin

The cosmological evolution of a scalar field is shaped by Hubble damping. Any non-gravitational couplings of the scalar with the primordial thermal bath generically contribute additional damping. Although rarely considered, such thermal damping could be the dominant dissipative effect. We derive approximate but highly general thermal-damping rates of scalar fields that modulate the masses of thermally populated particles. We extend previous results to cover cases of particular phenomenological interest where the scalar background oscillates sinusoidally but not necessarily slowly compared to the thermalization rates of the primordial bath. Based on these results, we estimate the thermal damping of scalars coupled to neutrinos linearly, to gluons quadratically, and to WIMPs linearly, and demonstrate its importance in certain parameter space of these models. We also estimate the thermal damping rates in models of QCD axion.
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Astrophysics of Galaxies

The dependence of the intracluster light fraction on galaxy cluster properties

Louisa Canepa, Sarah Brough, Mireia Montes et al. (+1 more)

We use machine learning to measure the intracluster light (ICL) fractions of 177 galaxy groups and clusters identified from Hyper Suprime-Cam Subaru Strategic Program imaging to explore how the ICL varies with the properties of its host cluster. We study the variation in ICL fraction with host cluster redshift, halo mass, and magnitude gap to investigate how the ICL develops over time, in various cluster environments, and with cluster relaxation. We find that there is a decreasing correlation with redshift (Spearman correlation $r_S=-0.604$, p-value $=9\times10^{-10}$), however this can be plausibly accounted for by including the effects of cosmological surface brightness dimming and the passive aging of stellar populations. There is a weak negative correlation with halo mass ($r_S=-0.330$, p-value $=8\times 10^{-5}$) where ICL fractions are higher in lower halo mass groups than higher halo mass clusters. We also find that there is a marginal positive correlation with magnitude gap ($r_S=0.226$, p-value = 0.01), indicating that relaxed clusters are more likely to host higher ICL fractions. These results are consistent with a scenario where the dominant formation mechanism of the ICL is galaxy-galaxy interactions such as tidal stripping, and demonstrates the capability of the method to easily construct large samples and study large-scale trends in the ICL fraction.
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All authors Louisa Canepa, Sarah Brough, Mireia Montes, Nina Hatch

Earth and Planetary Astrophysics

Predictions of the Nancy Grace Roman Space Telescope Galactic Exoplanet Survey. V. Detection Rates of Multiplanetary Systems in High Magnification Microlensing Events

Vito Saggese, Étienne Bachelet, Sebastiano Calchi Novati et al. (+34 more)

The Nancy Grace Roman Space Telescope will expand the reach of gravitational microlensing surveys by increasing the number of events monitored and the precision of their light curves. We investigate Roman's ability to detect triple-lens microlensing systems, cases where a foreground star with two bound exoplanets produces detectable anomalies in a microlensing event, using its planned high-cadence observations toward the Galactic bulge. We simulate a large set of high-magnification microlensing light curves based on Roman's expected survey characteristics. A detection criterion, based on a required $\chi^2$ improvement for a two-planet model, is applied to determine whether the second planet can be reliably distinguished from a single-planet (binary-lens) model. Our simulations show that the majority of two-planet microlensing events would be detectable with Roman. Events in which both planets are relatively massive (planet-star mass ratios of order $10^{-3}$), or in which the more massive planet occupies a favorable resonant configuration, produce strong central perturbations, resulting in detection efficiencies of roughly 90%. By contrast, systems with only low-mass planets ($q \sim 10^{-4}$) or with less favorable alignments generate much weaker signals, which often fall below the detection threshold. In general, the planetary mass ratios and the resulting caustic geometry (e.g., central caustic size in resonant versus wide/close orbits) are the dominant factors governing detectability. Taking into account the expected frequency of planetary systems and the fraction of high-magnification events, we estimate that Roman will detect a high-magnification triple-lens event in approximately 4.5% of multi-planet microlensing events, corresponding to about 64 events over the course of the full survey.
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All authors Vito Saggese, Étienne Bachelet, Sebastiano Calchi Novati, Valerio Bozza, Giovanni Covone, Farzaneh Zohrabi, Michael D. Albrow, Jay Anderson, Charles Beichman, David P. Bennett, Aparna Bhattacharya, Christopher Brandon, Sean Carey, Jessie Christiansen, Alison Crisp, William DeRocco, B. Scott Gaudi, Jon Hulberg, Macy J. Huston, Stela Ishitani Silva, Eamonn Kerins, Somayeh Khakpash, Katarzyna Kruszyńska, Casey Lam, Jessica R. Lu, Amber Malpas, Arjun Murlidhar, Marz Newman, Greg Olmschenk, Matthew Penny, Keivan G. Stassun, Alexander P. Stephan, Rachel A. Street, Takahiro Sumi, Sean K. Terry, Himanshu Verma, Weicheng Zang

Astrophysics of Galaxies

Little red dot variability over a century reveals black hole envelope via a giant Einstein cross

Zijian Zhang, Mingyu Li, Masamune Oguri et al. (+79 more)

"Little red dots" (LRDs) represent a new population of astronomical objects uncovered by JWST whose nature remains debated. Although many LRDs are suspected as active galactic nuclei (AGN), they show little variability on days-years timescales. We report the discovery of two gravitationally lensed LRDs at redshift $\sim$4.3 behind the cluster RXCJ2211-0350, one of which (RX1) is quadruply imaged with time delays spanning $\sim$130 years. RX1 exhibits intrinsic color and brightness variations of up to 0.7 magnitude among its images. These changes are consistent with blackbody-temperature variations of a photosphere, indicating long-term variability analogous to Cepheid-like pulsations but in a far more extended ($R \sim 2000$ AU) and massive ($M \gtrsim 10^6 \, M_{\odot}$) systems. These results suggest LRDs as a distinct class of AGN with stellar-like envelopes.
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All authors Zijian Zhang, Mingyu Li, Masamune Oguri, Xiaojing Lin, Kohei Inayoshi, Catherine Cerny, Dan Coe, Jose M. Diego, Seiji Fujimoto, Linhua Jiang, Guillaume Mahler, Jorryt Matthee, Rohan P. Naidu, Keren Sharon, Yue Shen, Adi Zitrin, Abdurro'uf, Hollis Akins, Joseph F. V. Allingham, Ricardo Amorín, Yoshihisa Asada, Hakim Atek, Franz E. Bauer, Maruša Bradač, Larry D. Bradley, Zheng Cai, Sebastiano Cantalupo, Christopher Conselice, Liang Dai, Pratika Dayal, Eiichi Egami, Daniel J. Eisenstein, Andreas L. Faisst, Xiaohui Fan, Qinyue Fei, Brenda L. Frye, Yoshinobu Fudamoto, Lukas J. Furtak, Miriam Golubchik, Mauro González-Otero, Yuichi Harikane, Tiger Yu-Yang Hsiao, Yolanda Jiménez-Teja, Jeyhan S. Kartaltepe, Tomokazu Kiyota, Anton M. Koekemoer, Kotaro Kohno, Vasily Kokorev, Nimisha Kumari, Ivo Labbe, Claudia D. P. Lagos, Conor Larison, Yongming Liang, Ray A. Lucas, Jianwei Lyu, Nicholas S. Martis, Georgios E. Magdis, Matteo Messa, Minami Nakane, Gaël Noirot, Rafael Ortiz III, Masami Ouchi, Justin D. R. Pierel, Marc Postman, Naveen Reddy, Massimo Ricotti, Daniel Schaerer, Raffaella Schneider, Charles C. Steidel, Wei Leong Tee, Roberta Tripodi, James A. A. Trussler, Hiroya Umeda, Francesco Valentino, Eros Vanzella, Feige Wang, Rogier Windhorst, Yunjing Wu, Zihao Wu, Hiroto Yanagisawa, Jinyi Yang, Fengwu Sun

Earth and Planetary Astrophysics

TESS phase curve of ultra-hot Jupiter WASP-189 b

J. A. Patel, D. Kitzmann, A. Brandeker et al. (+4 more)

The thermal structures of highly irradiated ultra-hot Jupiters can deviate substantially from those of cooler hot Jupiters. For planets orbiting rapidly rotating, and consequently oblate, host stars, photometric light curves provide a unique opportunity to measure the spin-orbit angle. Moreover, in systems with significant spin-orbit misalignment, the stellar oblateness can induce observable orbital precession. We wish to study the atmosphere and orbital architecture of an ultra-hot Jupiter WASP-189 b, orbiting around a hot A-type star. We use the photometric phase curves and gravity-darkened transits of WASP-189 b observed with the Transiting Exoplanet Survey Satellite (TESS), complemented with the archival observations from CHaracterising ExOPlanet Satellite (CHEOPS). We detected a phase curve signal with significant occultation depth of 203.4 (+16.2) (-16.3) ppm, while the nightside flux, -71.8 (+36.4) (-36.0) ppm, is consistent with zero at 2-sigma. We invert the phase curve signal to construct the temperature map of the planet. The map was subsequently used to estimate the Bond albedo and heat redistribution efficiency, the expected median ranges of which are found to be 0.19-0.35 and 0.09-0.41, respectively. Finally, we analysed gravity-darkened transits to find that the planet is in polar orbit with the spin-orbit angle of 89.46 (+1.08) (-1.08) deg. We found no hint of orbital precession while comparing our results with those from the literature. Our observations, together with atmospheric modelling, suggest that the dayside emission of WASP-189 b in TESS and CHEOPS bandpasses is dominated by thermal emission from an atmosphere with extremely inefficient heat transport and negligible contribution from reflected light.
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All authors J. A. Patel, D. Kitzmann, A. Brandeker, T. G. Wilson, A. Deline, M. Lendl, V. Singh

High Energy Astrophysical Phenomena · Cross-listed from gr-qc

On the treatment of thermal effects in the equation of state on neutron star merger remnants

Davide Guerra, Milton Ruiz, Michele Pasquali et al. (+3 more)

We present results from long-term, numerical-relativity simulations of binary neutron star mergers modeled using both, fully tabulated, finite-temperature, equations of state and their corresponding hybrid representations. The simulations extend up to 150 ms which allows us to assess the role of the treatment of finite-temperature effects on the dynamics of the hypermassive neutron star remnant. Our study focuses on the analysis of the spectra of the post-merger gravitational-wave signals and on how these are affected by the treatment of thermal effects in the two EOS representations. Our simulations highlight distinct differences in the GW frequency evolution related to the thermal modeling of the EOS, demonstrating that deviations from established quasi-universal relations become significant at late post-merger phases. Furthermore, we investigate the stability of the HMNS against convection. Employing both the Ledoux criterion, necessary condition for the development of convective instabilities, and the Solberg-Høiland criterion, a generalized criterion for axisymmetric perturbations based on a combined analysis of the Brunt-Väisälä frequency and of the epicyclic frequency, we show that differential rotation and thermal stratification in the HMNS give rise to local (yet sustained) convective patterns that persist beyond 100 ms after merger. Those convective patterns, while substantially different between tabulated and hybrid EOS treatments, trigger the the excitation of inertial modes with frequencies smaller than those attained by the fundamental quadrupolar mode, and are potentially within reach of third-generation GW detectors. The late-time excitation of inertial modes, previously reported in studies based on hybrid EOS, is fully supported by the tabulated, finite-temperature EOS simulations presented here, which account for thermal effects in a more consistent way.
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All authors Davide Guerra, Milton Ruiz, Michele Pasquali, Pablo Cerdá-Durán, Arnau Rios, José A. Font

Cosmology and Nongalactic Astrophysics

The spectrum of $n_s$ constraints from DESI and CMB data

Evan McDonough and Elisa G. M. Ferreira

We present the spectrum of $n_s$ constraints from current CMB data (Planck, ACT, SPT-3G) combined with DESI BAO data, and highlight the interplay of $n_s$ with the optical depth to reionization $\tau$. The spectral index $n_s$ of the primordial power spectrum provides a window into early universe, and constraints on $n_s$ play an important role in discriminating early universe models such as models of cosmic inflation. Historically constrained by cosmic microwave background (CMB) experiments, the constraints on $n_s$ shift upward when CMB data is combined with the latest baryon acoustic oscillation (BAO) data from the Dark Energy Spectroscopic Instrument (DESI). Recent work explained the origin of this and the relation to the BAO-CMB tension between CMB experiments and DESI BAO, and as a case study presented constraints on $n_s$ from the combination of Atacama Cosmology Telescope (ACT) DR6 data and DESI DR2 data. Here we present constraints from Planck (PR3 and PR4), ACT, the South Pole Telescope (SPT), and the combination of all three CMB experiments, CMB-SPA, with and without DESI DR2 BAO data, and with and without CMB lensing data. In all cases the constraint on $n_s$ is shifted upwards when DESI is included, with the largest shift exhibited by ACT. This is accompanied by a commensurate shift in the constraint on the optical depth to reionization $\tau$, which is again greatest for ACT. When CMB data are combined into CMB-SPA and combined with DESI the $n_s$ constraint disfavors at more than $2\sigma$ the inflation models preferred by Planck alone, such as Higgs, Starobinsky, and exponential $\alpha$-attractors, in favor of other models, such as polynomial $\alpha$-attractors. This work motivates the further study of the tension between CMB and DESI BAO data, and of the rich interplay between $n_s$ and $\tau$.
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High Energy Astrophysical Phenomena

PSR J0952-0607: Tightening a Record-High Neutron Star Mass

Roger W. Romani, Maya Beleznay, Alexei V. Filippenko et al. (+2 more)

We report on new orbit-minimum photometry and revised radial-velocity fitting that provide an improved measurement of the mass of the neutron star (NS) in pulsar PSR~J0952$-$0607 at $M_NS = 2.35\pm 0.11 M_\odot$. With its fast spin and unusually low magnetic field, this NS has evidently experienced unusual evolution, likely connected with its high mass, which is now $2.5\sigma$ above that of the heaviest pulsar with a white dwarf companion, as measured by Shapiro delay techniques. By tightening the mass measurement, we also raise the maximum (commonly called Tolman-Oppenheimer-Volkoff) NS mass to $M_{\rm TOV} > 2.27\,M_\odot$$(2.12\,M_\odot)$ at $1\sigma$$(3\sigma)$ confidence, which improves bounds on the dense-matter equation of state. While the statistical error decreases and systematic issues should be modest, uncertainties remain; we comment briefly on these factors and prospects for further improvement.
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All authors Roger W. Romani, Maya Beleznay, Alexei V. Filippenko, Thomas G. Brink, WeiKang Zheng

Astrophysics of Galaxies

Highly-ionized gas in lensed z = 6.027 Little Red Dot seen through [OIII] 88$\mu$m with ALMA

Kirsten K. Knudsen, Johan Richard, Mathilde Jauzac et al. (+8 more)

Determining the physical properties of galaxies during the first billion years after the big bang is key to understanding both early galaxy evolution and how galaxies contributed to the epoch of reionization. We present deep ALMA observations of the redshifted [OIII] 88um line for the gravitationally lensed ($\mu = 11.4\pm1.9$) galaxy A383-5.1 (z=6.027) that has previously been detected in [CII] 158um. Recent James Webb Space Telescope (JWST) imaging identified this sub-L* galaxy as a ”Little Red Dot” (LRD). With a line luminosity of $L_{\rm [OIII]} = (1.29\pm0.24)\times10^8$ L$_\odot$ (corrected for lensing magnification) A383-5.1 is one of the faintest galaxies with combined [CII] and [OIII] detections. The ALMA data reveal no dust continuum emission, consistent with previous observations. The high line luminosity ratio of [OIII]/[CII] $\sim 14\pm5$ is consistent with A383-5.1 being low-metallicity and dust-poor. The non-detection of dust continuum in bands 6 and 8 is consistent with the high [OIII]/[CII] ratio and suggests a presence of a strong ultraviolet radiation field, which would be less affect by dust attenuation, implying that galaxies of this type could contribute significantly to the ionization of the intergalactic medium. The presence of strong ionizing field could provide an important piece of information for understanding the nature of LRDs and their role in cosmic reionization.
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All authors Kirsten K. Knudsen, Johan Richard, Mathilde Jauzac, Tom J.L.C. Bakx, Thiago S. Goncalves, Eiichi Egami, Kiana Kade, Rahul Rana, Laura Sommovigo, Flora Stanley, Daniel P. Stark

Astrophysics of Galaxies

Resolving the molecular gas emission of the z~2.5-2.8 starburst galaxies SPT0125-47 and SPT 2134-50

K. Kade, M. Bredberg, K. Knudsen et al. (+4 more)

The comoving cosmic star formation rate density peaks at z~2-3, with dusty star-forming galaxies being significant contributors to this peak. These galaxies are characterized by their high star formation rates and substantial infrared luminosities. The formation mechanisms remain an open question for these galaxies, particularly with respect to how such intense levels of star formation are triggered and maintained. We aim to resolve CO(3-2) emission toward two strongly lensed galaxies, SPT0125-47 and SPT2134-50, at z~2.5-2.8 to determine their morphology and physical properties. We used high-resolution ALMA band 3 observations of CO(3-2) emission toward both sources to investigate their properties. We performed parametric and nonparametric lens modeling using the publicly available lens modeling software PyAutoLens. We divided the CO(3-2) emission line into two bins corresponding to the red and blue portions of the emission line and nonparametrically modeled the source plane emission for both bins. We performed a basic analysis of the morphology and kinematics in the source plane using nonparametric lens modeling of the red and blue bins. We found tentative evidence of a velocity gradient across both sources and no evidence of any clumpy structure, companions, or ongoing mergers. The previously calculated high star formation rates and low depletion times of both SPT0125-47 and SPT2134-50 suggest that these galaxies are undergoing a dramatic phase in their evolution. Given the lack of evidence of ongoing interactions or mergers in our source plane models, we suggest that the intense star formation was triggered by a recent interaction and/or merger. We also consider the possibility that these galaxies might be in the process of settling into disks.
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All authors K. Kade, M. Bredberg, K. Knudsen, S. König, G. Drouart, A. B. Romeo, T.J.L.C. Bakx

Instrumentation and Methods for Astrophysics

Improving Posterior Inference of Galaxy Properties with Image-Based Conditional Flow Matching

Mikaeel Yunus, John F. Wu and Benne W. Holwerda

Estimating physical properties of galaxies from wide-field surveys remains a central challenge in astrophysics. While spectroscopy provides precise measurements, it is observationally expensive, and photometry discards morphological information that correlates with mass, star formation history, metallicity, and dust. We present a conditional flow matching (CFM) framework that leverages pixel-level imaging alongside photometry to improve posterior inference of galaxy properties. Using $\sim10^5$ SDSS galaxies, we compare models trained on photometry alone versus photometry plus images. The image+photometry model outperforms the photometry-only model in posterior inference and more reliably recovers known scaling relations. Morphological information also helps mitigate the dust–age degeneracy. Our results highlight the potential of integrating morphology into photometric SED fitting pipelines, opening a pathway towards more accurate and physically informed constraints on galaxy properties.
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Cosmology and Nongalactic Astrophysics

Sensitivity of the Hongmeng 21cm experiment to scattering dark matter

Junsong Cang, Yu Gao and Yin-Zhe Ma

Scattering between dark matter and baryons can cool the intergalactic medium temperature and deepen the 21cm signal. Such interactions have been proposed to explain the unusually deep 21cm absorption signal reported by EDGES in 2018. We explore the potential to detect dark matter - baryon scattering with the Hongmeng project, an upcoming Moon-orbiting satellite experiment dedicated to measuring the global 21cm signal between redshifts $11-46$. We self-consistently forward-model the simulated sky-temperature data, jointly varying the astrophysical and foreground models. We show that even with a very conservative observational strategy in which the experiment only takes data when the Earth and the Sun are both shielded by the Moon, Hongmeng can tighten the current constraints on the cross section of dark matter - baryon scattering $\sigma_0$ by a factor of 39 after the full mission, which lasts for five years. The prospective upper limit on $\sigma_0$ can reach $5.4 \times 10^{-43} {\rm cm^2}$ for dark matter masses between 0.1 MeV and 0.3 GeV. Even after only one month of operation, an improvement by a factor of 4 relative to current $\sigma_0$ limits can be expected.
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Cosmology and Nongalactic Astrophysics

Line-of-sight shear in SLACS strong lenses II: validation tests with an extended sample

Natalie B. Hogg, Daniel P. Johnson, Anowar J. Shajib et al. (+1 more)

Strong gravitational lensing images are subject to shape distortions due to inhomogeneities along the line of sight. The leading order shape distortion is shear, which, if measurable, will be a complementary cosmological probe to traditional cosmic shear. In Hogg et al. (2025a), we modelled 23 of the SLACS strong lenses, studying the line-of-sight (LOS) shear under a variety of shear and mass model parametrisations. In this work, we successfully model 22 of an additional 27 lenses, extending our sample of LOS shear constraints to 45 in total. We find a mean shear magnitude of $0.11\pm 0.024$, showing that a significant fraction of the lenses modelled in this work possess LOS shears with unexpectedly large magnitudes, $|\gamma_{\rm LOS}| > 0.1$, even when an octupolar distortion is included in the lens mass. We further investigate if factors such as lens and source redshift, filter and PSF, or flux and signal-to-noise ratio in the lensed arcs correlate with shear. We find that none of these features play a statistically significant role in the production of unusually large shear magnitudes.
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All authors Natalie B. Hogg, Daniel P. Johnson, Anowar J. Shajib, Julien Larena

Solar and Stellar Astrophysics

The position and resolvability of blended point sources

Zephyr Penoyre

In this work we derive analytic expressions and numerical recipes for finding the effective observed position of sources close enough on sky that their Point Spread Functions (PSF), modelled as Gaussian profiles, overlap. In particularly we derive these for an elongated PSF, with a long and short axis, such as we would see from an instrument with a rectangular or elliptical mirror (relevant, for example, for the Gaia mission). We show that in this case the problem can be reduced to a one dimensional brightness profile with extrema along the line connecting the two sources, with an effective PSF width that depends on the relative orientation of the PSF and its degree of elongation. The problem can then be expressed in units of this effective width to be a function of the relative separation and light ratio alone (thus reducing to a rescaling of the un-elongated case). We derive the minimum light ratio, for a given separation and effective width, above which two sources will be resolved. We map out numerical procedures for finding the positions of these extrema across all possible cases. Finally we derive the positional offset and deviance associated with observing a fixed pair of blended sources from a variety of orientations, showing that this can be a significant source of excess noise.
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Astrophysics of Galaxies

Dust destruction by the supernova remnant forward shock in a turbulent interstellar medium

Tassilo Scheffler, Nina S. Sartorio, Florian Kirchschlager et al. (+3 more)

Context. While supernova remnants (SNRs) are observed to produce up to 1 M$_\odot$ of dust, the amount of dust destroyed by the forward shock (FS) is poorly constrained, raising the question whether they are net dust producers or destroyers. Aims. We aim to estimate the dust destruction efficiency of SNR FSs in a realistically turbulent interstellar medium (ISM) during their most destructive phase, and assess dust shielding by high density filaments during this period. Methods. We run 3D turbulence simulations for different turbulent Mach numbers (0-3) and average ISM densities (1-100 cm$^{-3}$) to resemble observations of the turbulent ISM. We then set off a supernova to trace its 3D magnetohydrodynamical evolution for 10 kyr. Finally, we run post-processing simulations to study the dust transport and destruction by the SNR FS, considering gas and plasma drag, kinetic and thermal sputtering, and grain-grain collisions, and either silicate or carbonaceous dust. Results. The dust destruction rate of the FS strongly depends on the average ISM density and turbulence strength, varying between 27-92% (0.85-11.0 M$_\odot$) in the studied 10 kyr. Overall, dust is less efficiently destroyed in a low density medium (1 cm$^{-3}$, 27-57%) than in intermediate (10 cm$^{-3}$, 46-92%) and high densities (100 cm$^{-3}$, 73-87%). The FS destroys 8-34% less dust in high Mach turbulence compared to a homogeneous medium. Furthermore, carbonaceous grains are more robust (up to 21% more) than silicates. Conclusions. Filaments can partly shield dust from destruction in the first 10 kyr, however, always more than 0.85 M$_\odot$ of dust is destroyed, making most SNRs dust sinks under the conditions explored in this work. The destruction efficiency of the SNRs with less than 1 M$_\odot$ of destroyed dust has not yet plateaued so that they are most likely also net dust destroyers by the end of their lifetime.
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All authors Tassilo Scheffler, Nina S. Sartorio, Florian Kirchschlager, Ilse De Looze, Michael J. Barlow, Franziska D. Schmidt

Astrophysics of Galaxies

Probing AGN Feedback in Dwarf Galaxies with Spatially Resolved NIR Coronal Lines from JWST

Archana Aravindan, Thomas Bohn, Gabriela Canalizo et al. (+20 more)

We present the first spatially resolved investigation of near-infrared coronal lines in dwarf galaxies hosting active galactic nuclei (AGN), using JWST/NIRSpec integral field spectroscopy. Coronal lines (CLs), which are forbidden transitions from highly ionized species with ionization potentials up to 450 eV, act as sensitive tracers of the AGN ionizing continuum and feedback processes. Across four dwarf galaxies with ionized gas outflows traced by the optical [O III] lines, we report the detection of 16 unique species of near-infrared CLs. Line ratio diagnostics indicate that photoionization from the AGN dominates the excitation of CLs. We find that the coronal line region in dwarf galaxies, traced by the various CLs, extends up to 0.5 kpc, and can constitute up to 10% of their host galaxy size. Correlations between CL luminosities and [O III] ionized gas outflow properties are consistent with a scenario in which AGN-driven outflows likely facilitate the detection of CLs and contribute to their extent. Several CLs, including [Si VI], [Si VII], and [Mg VIII], exhibit a secondary broad component with W$_{80}$ (the line width enclosing 80% of the total flux)> 300 km/s. If we interpret this spatially compact gas as part of an outflow, this would indicate that the outflowing gas includes a wide range of ionizations. The estimated energetics imply this highly ionized component is compact yet powerful enough to perturb gas in the central regions of the host dwarfs. These results indicate that AGN in low-mass galaxies may produce outflows capable of influencing their structure and evolution.
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All authors Archana Aravindan, Thomas Bohn, Gabriela Canalizo, Shobita Satyapal, Vivian U, Weizhe Liu, William Matzko, Sara Doan, Matthew Malkan, Lee Armus, Tohru Nagao, Tanio Diaz-Santos, Aditya Togi, Thomas S.Y. Lai, Sean T. Linden, Marina Bianchin, Yiqing Song, Loreto Barcos-Munoz, Aaron Evans, Hanae Inami, Kirsten Larson, Sabrina Stierwalt, Jason Surace