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宇宙工学・惑星科学・宇宙物理の最新プレプリント。

astro-ph.GA

AGN Feedback Models and AGN Demographics II: Comparing Predictions of Radiative and Total Feedback to Observations

Arjun Suresh, Michael R. Blanton

We evaluate the radiative-mode active galactic nucleus (AGN) feedback models of EAGLE, SIMBA, and TNG100 by comparing their predictions for the AGN-host galaxy relationship to new observational constraints. Owing to incomplete knowledge of the underlying physics, these models differ substantially, and it remains unclear whether any of them accurately reflect reality. In a previous study, based on the demographics of narrow line AGN, we constrained $F_{\mathrm{AGN}}$, the intrinsic fraction of ga…

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astro-ph.HE

Shock cooling emission from late-time mass loss in low-mass He star binaries

Samantha C. Wu, Anthony L. Piro

A subset of hydrogen-poor supernovae (SNe) exhibit signatures of interaction with nearby dense circumstellar material (CSM). These SNe may originate from interacting binary systems, in which the SN progenitor experiences intense mass loss when it overflows its Roche lobe close to core collapse. In this work, we explore the appearance of SNe from low-mass stripped star progenitors in binary systems, for a range of initial orbital periods and masses. We model the CSM based on the stripped stars' m…

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astro-ph.SRastro-ph.IMcs.LG

A Deep Learning Framework for Predicting Solar EUV Irradiance During Significant Flares

Sathvik Soman, Jason T. L. Wang, Haimin Wang, Haodi Jiang

We present FlareEUV, a multimodal deep learning framework for predicting daily extreme ultraviolet (EUV) irradiance at 6.5 nm over three consecutive days during significant solar flares, using multi-instrument observations from NASA's Solar Dynamics Observatory (SDO). We consider 33 significant flares in the period between 2011 and 2014 in Solar Cycle 24. The SDO observations include 13 co-aligned full-disk images, comprising eight AIA EUV/UV and five HMI magnetic/continuum products. FlareEUV le…

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astro-ph.IM

Characterising the response of an International LOFAR Station

Letizia Vincetti, Sai C. Susarla, Owen A. Johnson, Evan F. Keane, David J. McKenna, Tobia D. Carozzi, Gavin Ramsay, Oisin Creaner et al.

Phased-array radio interferometers with fixed antennas are a highly scalable design which can achieve a large gain. However they are complex systems and challenging to calibrate. Here we examine the response of an International LOFAR Station, the high-band antennas of the Irish LOFAR station. In modelling our measured responses, we account for projection effects, the frequency-dependence of the aperture efficiency and pulsar spectra, as well as sky and instrumental noise contributions. We perfor…

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astro-ph.GA

Systematic Effects in Gaia CRF Photometry Related to Scanning Geometry and BP/RP excess factor

Valeri V. Makarov

I report a previously undocumented, large-amplitude systematic dependence of the median Gaia $G$-band magnitude of CRF3 sources on \texttt{ra\_dec\_corr}, which reflects the preferred direction of scans, accompanied by a partially correlated trend in the BP/RP flux excess factor. Given the imminent release of Gaia DR4, the purpose of this note is alerting the community to this artifact.

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astro-ph.EP

Atmospheric retrieval evidence for water isotopologue HDO on exoplanet WASP-39b

Fabian Gruebel, Karan Molaverdikhani, Barbara Ercolano, Katy L. Chubb, Paola Caselli, Tommaso Grassi, Rosa Arenales-Lope, Dwaipayan Dubey et al.

Hydrogen-isotopologues are commonly used to trace the chemical processing and origin of hydrogen-bearing species throughout the Universe, however, their abundance remains unconstrained for extrasolar planets. Here, we report atmospheric retrieval evidence for the deuterated water molecule HDO in an exoplanet atmosphere, retrieved from James Webb Space Telescope transmission spectra of the hot Jupiter WASP-39 b, resulting in a deuterium-to-hydrogen ratio in water of $4.0^{+1.3}_{-1.1} \times 10^{…

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astro-ph.GA

Swing amplification in star-gas disks

Abhishek Hegade K. R., Chris Hamilton

Recent JWST and ALMA observations have revealed stellar bars and spirals in gas-rich galactic disks at redshifts as high as $z \simeq 4$. The simplest theoretical paradigm we have for understanding such non-axisymmetric features is the linear theory of swing amplification (SA) in the 2D shearing sheet. However, while the SA mechanism in a gaseous shearing sheet was first studied in 1965, and that in a collisionless stellar sheet in 1966, the coupled star-gas linear SA equations have never been s…

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astro-ph.GA

The Age-Thickness Relation as a Tracer of the Merger History of Disk Galaxies

Lekshmi Thulasidharan, Elena D'Onghia, Robert Benjamin, Ronald Drimmel, Eloisa Poggio

In the hierarchical framework of galaxy formation, disk galaxies are shaped by a sequence of mergers and interactions, yet reconstructing this history from observations remains challenging. We show that the merger history of a galaxy leaves measurable imprints in the vertical structure of its stellar disk. Using Milky Way analogues from the TNG50 simulations, we demonstrate that the Age-thickness relation, quantified by the dispersion of vertical stellar positions ($Δ_z$), encodes both the dynam…

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astro-ph.GAastro-ph.HE

Discovery of Optical Filaments in the North Polar Spur/eROSITA Bubble

Julian Shapiro

I report the discovery of optical filaments in H$α$, [O III], and [S II], coincident with $144\,\mathrm{MHz}$ structure, associated with the North Polar Spur (NPS) region of the eROSITA bubbles. The optical emission is identified in the Northern Sky Narrowband Survey, and contains distinct structure and potentially elevated $\text{[S II]}/\mathrm{H}α$ relative to typical high-$b$ outflows from the warm ionized medium (WIM). $Δ$-variance and power spectrum analysis of the NPS H$α$ shows a prefere…

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astro-ph.GA

Mid-Infrared Colors Vary with Galactic Environment: Contrasting Star-Forming Disks, Young Centers, and Quiescent Star-Formation Deserts

Debosmita Pathak, Karin M. Sandstrom, Adam K. Leroy, Ryan Chown, Daniel A. Dale, Hannah B. Koziol, Mansi Padave, Jessica Sutter et al.

We present $50{-}100\,$pc-resolution JWST/MIRI and NIRCam measurements of mid-infrared (mid-IR) color variations in the diffuse interstellar medium (ISM) of 71 nearby star-forming galaxies from the PHANGS-JWST survey. Mid-IR emission traces the dust column density, intensity ($U$) and hardness of the interstellar radiation field, and the physical state (charge, size) and abundance of polycyclic aromatic hydrocarbons (PAHs). Mid-IR colors that trace PAH band-ratios remain fairly constant in the d…

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astro-ph.GAgr-qc

Local morphology and asymmetry of galactic rotation curves in a kinetic gas transport framework: NGC 3198

Anton A. Lipovka, Anna A. Lipovka

We investigate whether the observed fine structure and asymmetry of non-averaged galactic rotation curves can be reconstructed directly from the observed HI distribution within the framework of a kinetic gas transport description. Using the observed HI density profiles separately for the approaching (north-eastern) side and the receding (south-western) side of the galaxy NGC~3198, we reconstruct the corresponding rotation curves based on the equation previously derived in \citet{Lipovka2022}. It…

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astro-ph.GAastro-ph.COastro-ph.IM

Reading Between the Lines: Forward Modeling Dust, Continuum, and Spectral Cleaning for Multi-Line Intensity Mapping

Anirban Roy, Rachel S. Somerville, Anthony R. Pullen

Line intensity mapping (LIM) offers a tomographic view of galaxy evolution by measuring the aggregate emission from unresolved galaxies. In the optical and near-infrared, the line emission is accompanied by much brighter continuum emission that must be removed to recover line auto- and cross-power spectra. We develop a forward-modeling framework using a $\sim2$deg$^2$ lightcone drawn from a cosmological $N$-body simulation populated with galaxies using a physics-based semi-analytic model (SAM).…

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astro-ph.SRastro-ph.GAastro-ph.IM

A Probabilistic Framework for Population Studies of the Solar Neighborhood: Application to SDSS-V and Gaia

Ilija Medan, Keivan G. Stassun, Zachary Way, Guy S. Stringfellow, Alexandre Roman-Lopes, Jiadong Li, Madeline Lucey, Andrew R. Casey et al.

Studies of the Solar Neighborhood require spectroscopic follow-up of stars identified in astrometric surveys to fully characterize their physical properties. The SDSS-V Solar Neighborhood Census (SNC) is a dedicated program to observe stars within 100~pc. However, due to competing observing programs and fiber assignment constraints, the resulting sample carries severe and complex selection effects. A framework is presented for characterizing the selection function of the SDSS-V SNC relative to t…

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astro-ph.GA

Rapid growth in a dual AGN during a gas-rich merger at z~4.5

Hyewon Suh, Roberto Decarli, Emanuele Paolo Farina, Julia Scharwächter, Mar Mezcua, Giorgio Lanzuisi, Federica Loiacono, Brian C. Lemaux et al.

The late stages of galaxy mergers - when two supermassive black holes (SMBHs) reach kiloparsec-scale separations - represent a critical phase for understanding SMBH growth, galaxy co-evolution, and the progenitors of low-frequency gravitational waves. Yet confirmed close-separation (<3 kpc) dual active galactic nuclei (AGNs) remain confined to the local Universe, despite predictions that such systems should be common in the merger-rich early Universe. Here we report the discovery of LID-1166, a…

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astro-ph.IMastro-ph.GAphysics.comp-ph

A Scalable Fast Multipole Method Poisson Solver for the RAMSES code: II. Adaptive Mesh Refinement and Adaptive Time Stepping

Jun-Young Lee, Romain Teyssier

We present an extended implementation of a scalable, O(N) Poisson solver based on the fast multipole method (FMM), fully compatible with adaptive mesh refinement (AMR) and adaptive time stepping (ATS) within the RAMSES framework. Building on the unigrid algorithm in Lee & Teyssier (2026), we introduce several novel elements, including the use of multiple FMM trees, one for each AMR level, a merged FMM tree for all active levels to optimize neighbor searches, and the introduction of the concept o…

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astro-ph.HEhep-exhep-ph

Four, One, and None: Quantifying the Ultra-High-Energy Neutrino Anomaly Across ANITA-IV, KM3NeT, and IceCube

Dibya S. Chattopadhyay, Carlos A. Argüelles, Vedran Brdar

The four near-horizon neutrino-like events reported by ANITA-IV and the ultra-high-energy track-like event KM3-230213A observed by KM3NeT imply neutrino event rates that are in tension with the absence of corresponding events at IceCube. In this work, we perform a joint analysis of these events, taking into account the absence of any corresponding ones at IceCube. We construct semi-analytic, energy- and direction-dependent effective areas for the three detectors and account for the time-dependen…

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astro-ph.GAastro-ph.HE

Extreme Variability Reveals How the Eddington Ratio Regulates Coronal Power in Active Galactic Nuclei

Arghajit Jana, Claudio Ricci, Franz E. Bauer, Kriti Kamal Gupta, Benny Trakhtenbrot, Alessia Tortosa, Ruancun Li, Luis C. Ho et al.

The bolometric luminosity ($L_{\rm bol}$) of active galactic nuclei (AGNs) is a key tracer of accretion physics, but its direct determination is often hindered by limited spectral coverage and contamination of the host galaxy. Bolometric corrections ($κ_λ = L_{\rm bol}/L_λ$) offer a practical means of estimating $L_{\rm bol}$, with the X-ray bolometric correction ($κ_{\rm 2-10}$) being crucial for exploring the coupling between the accretion disk and the X-ray corona. Here we present multi-epoch…

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astro-ph.GA

A pilot sample of Planck-selected strongly lensed sub-mm galaxies: NOEMA observations and physical characterisation

Leonardo Trobbiani, Matteo Bonato, Ivano Baronchelli, Gianfranco De Zotti, Mattia Negrello, Marika Giulietti, Cristian Vignali, Marcella Massardi et al.

The extreme brightness of high-$z$ strongly lensed galaxies detected by Planck surveys, thanks to their exceptionally large gravitational magnifications, offers a unique opportunity to investigate in extraordinary detail their structure and kinematics during their active star-formation phase. As a step in this direction, we present and analyse NOEMA imaging and spectroscopic data for four lensed high-z galaxy candidates. We performed continuum and line imaging of the sources at 2 and 3 mm bands…

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astro-ph.SRastro-ph.GA

Large Magellanic Cloud Globular Clusters in the Near-infrared. I. RR Lyrae in Reticulum

Anupam Bhardwaj, Susmita Das, Prashant Nishad, Marina Rejkuba, Giulia De Somma, Marcella Marconi, Chow-Choong Ngeow, Vincenzo Ripepi et al.

Reticulum is an old, metal-poor, and sparsely populated globular cluster in the outer regions of the Large Magellanic Cloud (LMC) and hosts a rich population of RR Lyrae stars. Being as close as possible to a single stellar population with negligible metallicity spread and low reddening, Reticulum is an ideal laboratory for testing stellar pulsation models and calibrating population II distance indicators. We present homogeneous multi-epoch near-infrared (NIR, JHKs) observations of RR Lyrae vari…

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astro-ph.GA

The GOLIATH Survey: OVI Absorption Reveals CGM Evolution through the Starburst-to-Quiescent Transition in Massive Galaxies

Derick Flores, Rongmon Bordoloi, Jason Tumlinson, J. Christopher Howk, Nicolas Lehner, Mary Rickel, Benjamin Oppenheimer, Joseph Burchett et al.

We present the GOLIATH survey (Galaxies, Outflows, and the Lifecycle of Immense, Active, Transforming Halos), a study of the multiphase circumgalactic medium (CGM) of massive ($\langle\log M_\star/M_\odot\rangle \approx 11$), blue ($u-r < 1.65$) starburst and post-starburst galaxies at $\langle z\rangle \approx$ 0.43. This work characterizes the warm-hot CGM through OVI absorption in the inner halo ($R/R_{\rm vir} \leq 0.6$) of these rare systems. Across the star-forming population, OVI column d…

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astro-ph.COastro-ph.GA

Cosmic CORALS: Timing the Universe with high-z star clusters

Elena Tomasetti, Martin Millon, Licia Verde, Frédéric Courbin, Raul Jimenez, Michele Moresco, Carmela Lardo, Andrea Cimatti et al.

In this work, we explore the potential of anchoring the age-redshift relation across cosmic time by probing the oldest star clusters at high redshift, now observed thanks to the James Webb Space Telescope in strongly lensed fields. As a case study, we consider one of the highest-redshift systems observed, the Cosmic Gems arc at $z=9.625$. We perform image deconvolution of multi-band JWST imaging, identifying a total of 20 point sources along the arc. We derive the stellar ages through a cosmolog…

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astro-ph.GAastro-ph.CO

The first dusty galaxies across $6 \lesssim z \lesssim 14$: Blue monsters, red monsters, and the bimodality of dust content in early galaxies

Sergio Martínez-González, Casiana Muñoz-Tuñón, Santiago Jiménez

JWST has revealed galaxies at $z>10$ with extremely blue UV-continuum slopes approaching $β_{\rm UV}\lesssim-2.4$, and low inferred dust contents. At similar redshifts, JWST and ALMA reveal dusty massive systems reaching $β_{\rm UV}\gtrsim-1$. We aim to explain blue monsters and red monsters at $z\gtrsim10$ as different outcomes of supernova dust retention in clustered star-forming systems and connect this bimodality to dusty massive galaxies at $z\simeq6$--7. We model dust removal in a cluster-…

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astro-ph.IMastro-ph.COcs.CVstat.ML

Strong Gravitational Lensing Posterior Sampling in Pixel-Space Using Diffusion Models and Recurrent Inference Machines

Guillaume Payeur, Laurence Perreault-Levasseur, Gabriel Missael Barco, Yashar Hezaveh

Modeling galaxy-galaxy strong gravitational lenses to infer the brightness of the source galaxy and the mass distribution of the foreground galaxy is computationally challenging, particularly for high-resolution, high signal-to-noise ratio observations. In this regime, high-dimensional representations of both the source and the foreground mass distribution are necessary to model the data down to the noise level. This inference problem has been challenging for both traditional and machine learnin…

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astro-ph.HEgr-qc

Gravitational-Wave Sky Mapping with Pulsar Timing Arrays: The Full Earth-Pulsar Response and Fundamental Resolution Limits

S. A. Andrianov, S. M. Kopeikin

Pulsar timing arrays (PTAs) are the only means to observe nanohertz gravitational waves (GWs). While current analyses primarily exploit the Earth term, the full detector response encodes additional directional information in the pulsar terms. We develop a GW sky-mapping framework based on the complete Earth--pulsar response and a tensor spherical harmonic decomposition of the GW field. This yields closed-form response functions for an elementary baseline and casts PTA sky reconstruction as a lin…

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astro-ph.EP

Refined parameters, formation, and dynamical stability of the wild exoplanet system K2-312=HD 80653

L. Naponiello, E. Poretti, K. Rice, A. S. Bonomo, L. Malavolta, M. Stalport, A. Vanderburg, C. Ziegler et al.

The architecture of planetary systems hosting ultra-short-period (USP) planets is a key diagnostic for understanding formation and migration scenarios. The presence of outer giant companions in these systems is of particular interest to test theories regarding dynamical effects and pebble accretion. We present an extended radial velocity (RV) monitoring of the bright star K2-312=HD80653, known to host a rocky USP super-Earth ($P_b=0.720$d). Previous studies identified a long-term trend and subse…

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hep-exastro-ph.IMquant-ph

Dark matter searches with a 13 meV threshold superconducting sensor array

Christopher Albert, Lanqing Yuan, Jacob Harris, Ritoban Basu Thakur, Andrew Bear, Karl K. Berggren, Christopher Cappiello, Christopher Curwen et al.

Many well-motivated dark matter models predict meV-scale energy deposits in interactions with terrestrial experiments, but this regime is challenging to probe due to a lack of mature single-quantum detectors. Here we report results from QUALIPHIDE (QUAntum LImited PHotons In the Dark Experiment), a cryogenic dark matter search using a $41$-pixel array of energy-resolving microwave kinetic inductance detectors with a $13$ meV threshold, simultaneously used to look for both conversion photons from…

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astro-ph.EPphysics.space-ph

Three-Dimensional Dust Distribution in the Jovian System from Juno/Waves Observations: Insights into the Halo Ring and Magnetospheric Dust

Yuqi Zhang, Shengyi Ye, Yuting Li, Wenyue Li, Guangzhou Wang, Xinya Duanmu

Discoveries regarding the dusty rings of Jupiter and the Galilean satellites' dust environment have been continuously refined by orbiters and flybys. Leveraging Juno Waves instrument electric field data, we developed a hybrid recognition framework, coupling Kvammen et al.'s Convolutional Neural Network (CNN) with rule-based differential peak analysis, to systematically map the Jovian dust environment. This automated pipeline successfully identified over 150,000 dust impacts, effectively isolatin…

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gr-qcastro-ph.IMphysics.ins-det

Optomechanical transfer factors for scattered light noise estimations in the beamtubes of ground-based gravitational wave detectors

M. Andrés-Carcasona

Scattered light is a relevant noise source in current ground-based gravitational-wave detectors and a critical design concern for next-generation observatories. Beamtube scattered light estimates usually combine optical propagation simulations with analytical couplings that do not fully propagate the frequency-dependent optomechanical response of the interferometer to the strain readout. In this work, we use improved analytical transfer factors to convert scattered-light field perturbations in t…

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gr-qcastro-ph.HE

GWTC-5.0: Tests of General Relativity

The LIGO Scientific Collaboration, the Virgo Collaboration, the KAGRA Collaboration, A. G. Abac, A. Abe, I. Abouelfettouh, F. Acernese, K. Ackley et al.

The signals from the LIGO-Virgo-KAGRA network of gravitational-wave (GW) detectors allow us to perform sensitive tests of general relativity (GR) in the dynamical and strong-field regime of gravity. We present the results of seven tests of GR using the observed binary signals in the fifth GW Transient Catalog (GWTC-5.0), i.e., up to and including the second part of the fourth observing run (O4b). We restrict our analysis to the confident signals, henceforth called events, observed by at least tw…

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astro-ph.IMastro-ph.HEastro-ph.SR

Astrophysics on GPUs: introducing AGILE 1.0

Oliver Porth, Adrian Kelly, Olaf Willocx, Hao Wu, Jesse Vos, Yuhao Zhou, Héctor R. Olivares Sánchez, Leon Oostrum et al.

We present AGILE, a GPU-enabled adaptive mesh refinement (AMR) framework for the solution of (near-) conservation laws which occur in astro- and solar-physical applications. AGILE is written in modern fortran 2003, inherits a part of its modules and mesh handling from MPI-AMRVAC, and achieves excellent GPU performance via OpenACC offloading. We here discuss the design decisions which enable AGILE to perform cost-efficient and scalable deeply nested AMR simulations with moderate block sizes of e.…

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