研究動向

gr-qcastro-ph.HE2026年10月9日

Listening to the Horizon: Probing Near-Horizon Reflectivity with GW250114

R. Prasad, Subhodeep Sarkar, Sudipta Sarkar

Testing the horizon properties of astrophysical black holes is a central goal of gravitational-wave astronomy. The recently identified Direct Wave (DW), a prompt non-quasinormal component of GW250114, provides a new probe of near-horizon physics. While it remains unclear whether the DW itself carries horizon information, we show that it enables a novel null test of horizon reflectivity. If the remnant is an exotic compact object (ECO) with a partially reflecting surface, inward plunge radiation…

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astro-ph.GAastro-ph.HE2026年10月9日

ACORN I. Massive Black Hole Seeding and Tidal Disruption Events from Star Clusters in Cosmological Simulations

Yihao Zhou, Tiziana Di Matteo, Claire E. Williams, Aklant Kumar Bhowmick, Marta Reina-Campos, Carl L. Rodriguez, Elena González Prieto, Laura Blecha et al.

JWST has revealed massive star clusters at $z\gtrsim 6$, which provide promising environments for massive black hole (MBH) seed formation. We introduce a new MBH seeding model for cosmological simulations, physically motivated by the runaway collisions in star clusters. Subgrid star clusters are generated according to the local ISM and evolved through stellar evolution and two-body relaxation. The masses of MBH seeds formed through runaway collisions are determined by the properties of their hos…

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astro-ph.GA2026年10月9日

Inflow-driven galaxy evolution - II: A hierarchy in the scaling relations of star-forming galaxies

Kai Wang, Carlton Baugh, Sownak Bose, Shaun Cole, Carlos S. Frenk, Cedric Lacey, Julio F. Navarro, Kyle A. Oman et al.

The star-forming main sequence (SFMS; $M_\star$--sSFR), the gas-to-stellar mass relation ($M_\star$--$M_{\rm gas}/M_\star$), and the mass--metallicity relation (MZR; $M_\star$--$Z_{\rm gas}$) are three core scaling relations for star-forming galaxies, and together they encode the information about the baryon cycle that operates during galaxy evolution. We investigate how these relations emerge by modelling the gas flows that regulate the baryon cycle, using both an ideal and a cosmological gas f…

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astro-ph.HE2026年10月9日

Funnel Leakage of the Wien Fireball in the Early Nebula after a Binary Neutron Star Merger

Shao-Ze Li, Yun-Wei Yu, He Gao, Peng-Cheng Yang, Yu Qu

A newborn neutron star (NS) that survives after a binary NS merger can inject its rotational energy into the surrounding ejecta while the ejecta are still optically thick. The injected energy is redistributed by the pair cascade, and the nebula becomes a radiation-dominated plasma composed of photons and e^+- pairs. Compton scattering then governs the energy exchange while the photon number is conserved in scattering. This nebula is evolved with a one-zone model that includes pair creation, anni…

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astro-ph.HE2026年10月9日

A morphological search for stable year-scale modulation in gamma-ray blazars

Adithiya Dinesh, Alberto Domínguez, Alba Rico, Pablo Peñil, Marco Ajello, Sara Buson

Year-scale quasi-periodic oscillations (QPOs) in blazar gamma-ray light curves have been proposed as signatures of supermassive binary black holes and precessing jets. Red noise can mimic periodicity, and detection alone does not establish persistence or period stability. We develop and calibrate a morphological framework to characterize year-scale modulation and constrain the incidence of stable modulation in blazars. We analyze 120 Fermi-LAT light curves spanning 18.1 yr. Singular spectrum ana…

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quant-phastro-ph.HE2026年10月9日

Quantum Co-Design of Inhomogeneous Many-Body Neutrino Fast Flavor Transformation

Zoha Laraib, Sherwood Richers, Alessandro Baroni, Kathleen Hamilton, In-Saeng Suh

Dense-neutrino flavor evolution is a quantum many-body problem whose fully correlated treatment becomes rapidly more expensive with increasing particle number and spatial structure. We develop a \texttt{QCNO} quantum simulation code that maps a inhomogeneous forward-scattering neutrino Hamiltonian with advection and finite-range interactions to TEBD2 product-formula quantum circuits, and connects ideal many-body simulation, backend-aware execution, and fault-tolerant resource estimation within t…

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astro-ph.SR2026年10月9日

Rotation period of the O giant xi Persei: Coexistence of cyclic and periodic variability. A weakly magnetic candidate star

H. F. Henrichs, N. P. Sudnik, A. David-Uraz

OB stars exhibit line profile variability, often associated with rotation; notably, in their UV wind-sensitive lines where discrete absorption components tend to recur cyclically. We searched for periodicity in spectral regions of the O7.5III(n)((f)) star xi Persei formed very close to the star. The NIV 1718 A line was identified as the most uncontaminated spectral with a large and homogeneous available dataset is available: 307 IUE spectra over 12 years and 11 STIS spectra taken 21 years later.…

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astro-ph.SR2026年10月9日

Rotation period of the O giant xi Persei: Coexistence of cyclic and periodic variability. A weakly magnetic candidate star

H. F. Henrichs, N. P. Sudnik, A. David-Uraz

OB stars exhibit line profile variability, often associated with rotation; notably, in their UV wind-sensitive lines where discrete absorption components tend to recur cyclically. We searched for periodicity in spectral regions of the O7.5III(n)((f)) star xi Persei formed very close to the star. The NIV 1718 A line was identified as the most uncontaminated spectral with a large and homogeneous available dataset is available: 307 IUE spectra over 12 years and 11 STIS spectra taken 21 years later.…

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astro-ph.GA2026年10月9日

JWST CAPERS: Spectroscopic evaluation of very high redshift galaxy candidates

Callum T. Donnan, Mark Dickinson, Lorenzo Napolitano, Pablo Arrabal Haro, Anthony J. Taylor, Hollis B. Akins, Ryan Begley, Davide Bevacqua et al.

JWST/NIRCam imaging has enabled efficient selection of a large number of galaxy candidates at very high redshifts. Accurate and robust selection is crucial for statistical analyses, such as measurement of the ultraviolet luminosity function (UV LF). A variety of selection methods and criteria have been proposed in the literature. We evaluate the selection methodology of galaxy candidates at $z\geq8.5$ using 183 candidates with secure spectroscopic redshifts obtained from the CAPERS JWST/NIRSpec…

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astro-ph.IM2026年10月9日

Data Representation Matters: Optimizing Machine Learning for X-ray Source Classification by Leveraging Spatio-Spectral Information

Maggie Lieu, Ivan Valtchanov, Marguerite Pierre, Esin Gulbahar, Elias Koulouridis, Iván Muñoz Rodríguez, Lucio Chiappetti

Distinguishing between faint extended X-ray sources is a fundamental yet challenging task in X-ray surveys. This paper presents a benchmark comparison of convolutional neural network models for classifying simulated XMM-Newton observations of AGN and galaxy clusters, focusing on the impact of data representation and interpretability of that data. We evaluate 1D, 2D, 2D+1D, and 3D CNNs trained on distinct data representations derived from simulated XMM-Newton observations of AGN and clusters: 1D…

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astro-ph.IMastro-ph.CO2026年10月9日

Opening the Black Box: What Neural Networks Learn from Pulsar Timing Array Data

James Alvey, Andrea Mitridate, Mauro Pieroni, Joseph D. Romano

In recent years, simulation-based inference (SBI) methods have been proposed to address several data-analysis challenges faced by existing and planned gravitational-wave experiments. For example, SBI classification has recently been shown to significantly improve the prospects for detecting anisotropies in pulsar timing array (PTA) data. In this work, we use a simple toy model of a PTA to provide a more pedagogical explanation of how, and under which circumstances, SBI-based detection can improv…

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physics.ins-detastro-ph.IMhep-ex2026年10月9日

Cavity Characterization for the Princeton Axion Search

Nate Otto, Jianyang Fu, Joelle-Marie Begin, Saptarshi Chaudhuri, Roman Kolevatov, Lyman Page, Joe Wiedemann

The Princeton Axion Search (PXS) targets the mass window $0.8\text{--}2.1~μ\text{eV}$ (corresponding to frequencies $200\text{--}500~\text{MHz}$) at DFSZ sensitivity. The experiment, a haloscope, will use a cylindrical copper-plated aluminum cavity of $700~\text{mm}$ diameter and $1022~\text{mm}$ height, immersed in a $5~\text{T}$ solenoidal magnetic field. A $152~\text{mm}$ diameter tuning rod spanning the height of the cavity rotates to tune the primary mode resonance from $390\text{--}480~\te…

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astro-ph.EP2026年10月9日

Longitudinal distribution of Io's dayside atmospheric density

R. S. Giles, J. R. Spencer, T. K. Greathouse, C. C. C. Tsang, E. Lellouch, M. A. López-Valverde

Since 2001, we have used the TEXES high resolution mid-infrared spectrograph at NASA's Infrared Telescope Facility to study the density of Io's SO$_{2}$-dominated atmosphere. The spectra cover several SO$_{2}$ absorption lines near 530 cm$^{-1}$ and are used to retrieve the equatorial SO$_{2}$ column density. In addition to covering a long time period, our 191 independent observations also cover the full range of Io central longitudes, allowing us to study the longitudinal variability of Io's da…

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astro-ph.EP2026年10月9日

Gen-EBM: an energy balance model for terrestrial planets. Climate multistability from snowball to post-runaway greenhouse climates

Siddharth Bhatnagar, Emeline Bolmont, Maura Brunetti, Jérôme Kasparian, Tim Kallioinen, Marine Leyvraz, Guillaume Chaverot, Yonatan Birhanu Haile et al.

Climate multistability and tipping points are fundamental properties of planetary climates that depend sensitively on climate feedbacks. We introduce the Geneva Energy Balance Model (Gen-EBM), a new 1-D latitudinal EBM for rapid exploration of terrestrial planet climates, and use it to investigate how planetary rotation, eccentricity, and thermal inertia shape climate attractors and multistability. Gen-EBM is implemented in Rust and builds on previous exoplanet EBMs by incorporating a temperatur…

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astro-ph.HEgr-qc2026年10月9日

Evidence for orbital eccentricity supports a hierarchical origin for GW231123

Baoxiang Wang, Tao Yang, Zhoujian Cao, Bin Hu, Xikai Shan, Rong-Gen Cai

GW231123 is the most massive binary black hole merger observed to date and one of the most intriguing hierarchical merger candidates in the pair-instability mass gap. Its exceptionally large inferred component spins and remarkably short in-band duration make the source highly sensitive to waveform physics near merger. Here we show that GW231123 is better described as an eccentric binary black-hole merger. We analyse data over 11--448 Hz using the eccentric, spin-precessing effective-one-body wav…

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astro-ph.HEgr-qc2026年10月9日

Autocorrelation in black hole flare movies: Departures from Kerr

Fang-Stars Wei, Zelin Zhang, Zhenyu Zhang, Bin Chen

Autocorrelation in black hole movies encodes the time delays and angular separations between gravitationally lensed images, offering a means of testing the spacetime geometry. Using an orbiting hot spot in the parametrized Johannsen-Psaltis metric with a single deformation parameter, we investigate the ability of lensing-induced correlations to distinguish departures from Kerr. From ray-traced movies, we extract the slope (k) and intercept (b) of an approximately linear secondary ridge in the ti…

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astro-ph.GAastro-ph.CO2026年10月9日

Modeling CO Line Luminosity Using FIRE Simulations: I. Methodology and Validation of Molecular Gas and CO Abundance

Doğa Tolgay, Norman W. Murray, Dongwoo Chung, J. Richard Bond, Nathan J. Carlson, Robert Feldmann, Andrew Wetzel, Guochao Sun et al.

We present a post-processing pipeline that predicts CO line luminosities, molecular hydrogen masses, and CO abundances for galaxies in the Feedback in Realistic Environments (FIRE-2) simulations, as a first step toward CO response functions for line intensity mapping mocks. SKIRT gives the radiation field reaching each gas cell. CLOUDY, tabulated on a five-parameter grid (metallicity, density, turbulent velocity, radiation field, cloud scale) and interpolated, gives $L'_{\rm CO(1-0)}$ and the $\…

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physics.plasm-phphysics.space-ph2026年10月9日

Kinetic wave activity and proton heating in 3D hybrid simulations of decaying balanced and imbalanced Alfvénic turbulence

C. A. González, T. A. Bowen, A. Mallet, A. Tenerani

We investigate turbulent dynamics from large to sub-proton scales, the kinetic wave activity and resulting proton heating in three-dimensional hybrid-kinetic simulations of freely decaying balanced and imbalanced Alfvénic turbulence. We considered initial fluctuations with same amplitude and spectral shape but different degrees of correlation between velocity and magnetic field perturbations (i.e., normalized cross-helicity), which define the corresponding turbulent regimes. We found that our ba…

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astro-ph.HEastro-ph.GA2026年10月9日

Discovery of the Slowest Radio Pulsar in the Small Magellanic Cloud

Weiyu Wang, Rahul Sengar

We report the discovery of a new radio pulsar PSR J0103$-$72 in the Small Magellanic Cloud (SMC) through a reanalysis of Parkes/Murriyang archival observations targeting supernova remnants and pulsar-wind nebulae in the SMC. Previously two pulsars were discovered in these observations, and PSR J0103$-$72 is the third which we independently detected in two observations of its target field. It has a spin period of 1.327 sec and a dispersion measure (DM) of $272\pm13~\mathrm{pc\,cm^{-3}}$, making i…

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astro-ph.GAastro-ph.CO2026年10月9日

Too many or too bright? Status and perspectives in the study of the UV Luminosity Function at z>10

A. Fontana, H. Atek, V. Bromm, A. J. Bunker, M. Castellano, P. Dayal, F. D'Eugenio, D. Elbaz et al.

The finding that galaxies in the first 500Myr were much more numerous and/or brighter than expected is often cited as one of the main discoveries of the James Webb Space Telescope in its first four years of operation. This result is now solidly based on an impressive number of surveys that have detected, spectroscopically confirmed, and characterized a relatively large sample of galaxies up to z=14.44, the redshift of the most distant galaxy currently known. This finding has motivated the introd…

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astro-ph.SRastro-ph.GA2026年10月9日

EWOCS-XI: Anisotropic expansion and shear in the cluster Westerlund 1. A 2D kinematic analysis with Gaia DR3

L. Prisinzano, F. Damiani, C. Ordenes-Huanca, M. Tarantino, S. Sciortino, N. J. Wright, V. Almendros-Abad, M. Andersen et al.

Westerlund 1 (Wd1) is one of the Milky Way's most massive young clusters, in which heavy extinction and field contamination have historically hampered its kinematic characterization. We aim to assess Wd1's internal kinematics, dynamical state, and formation scenario. Using a robust 5D clustering approach, we identified 559 bona fide members. We modeled their proper motions via a 2D first-order Taylor expansion to derive the velocity gradient tensor, mapping expansion, rotation, and shear. Restri…

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astro-ph.HEastro-ph.SRhep-ph2026年10月9日

An updated model of neutrino emission from proto-neutron stars

Matteo Ballelli, Federica Pompa, Christoph Ternes, Marco Drago, Giulia Pagliaroli

We present an improved parametric model for neutrino emission from core-collapse supernovae that directly connects neutrino luminosity and average energy to stellar properties during emission. Our model incorporates two critical physical processes: convection within the proto-neutron star and the evolution of the neutrinosphere radius during the early emission phase. Using simulated datasets of supernova neutrino events in the Super-Kamiokande detector, we assess the sensitivity to astrophysical…

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astro-ph.GA2026年10月8日

Binding Energies of Astrophysically Relevant Molecules on CO$_2$ Clusters: Benchmarking and the Donor-Acceptor Origin of Surface-Dependent Binding

Aneesa Ahmad, Catherine Walsh, Stefan Vogt-Geisse

Carbon dioxide (CO$_2$) is among the most abundant interstellar ices and has been observed by JWST in water-rich mixtures and pure CO$_2$ environments. Astrochemical models adopt binding energies (BEs) measured on water ice because few BEs are available for CO$_2$ ice. We calculate BE distributions for twelve adsorbates (N$_2$, CH$_4$, HCl, C$_2$H$_2$, H$_2$S, HF, HCN, H$_2$CO, HCOOH, HNC, CH$_3$OH, H$_2$O) on CO$_2$ clusters containing two to five molecules using DFT calibrated against CCSD(T)/…

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astro-ph.IM2026年10月8日

On-chip filled array hyperspectral kinetic inductance detectors (FHYKID) for line intensity mapping

Emile Prêle, Martino Calvo, Usasi Chowdhury, Gregory Garde, Florence Levy-Bertrand, Alessandro Monfardini

The next generation Line Intensity Mapping (LIM) experiments will require very high throughput instrumentation, and as a consequence high pixel counts focal planes. For the study of the [CII] line in the redshift range z=7-8, we develop a hyperspectral filled focal plane (FHYKID) operating in the range 210-235 GHz and with a spectral resolution reaching 120. The spectral filtering is achieved thanks to planar Slot Split Ring Resonators (SSRR) coupled to Lumped Element Kinetic Inductance Detector…

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astro-ph.SR2026年10月8日

Volume Dependence of Helicity-based Eruption Diagnostics in Recurrent Coronal Jets

Chang Zhou, Jinhan Guo, Yang Guo, Jiajia Liu, Zekun Lu, Yuhang Gao

Recurrent solar coronal jets originate from the same source region, providing a useful setting for studying the buildup, redistribution, and release of magnetic energy and helicity. However, how these quantities can characterize magnetic evolution and the onset conditions of the eruptions remains unclear. We perform a full three-dimensional (3D) thermodynamic magnetohydrodynamic simulation of recurrent jets driven by converging motions imposed at the bottom boundary. The simulation naturally pro…

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astro-ph.EP2026年10月8日

Size, Shape, and Geometric Albedo of Dwarf Planet Quaoar's Largest Satellite Weywot

Cameron Collyer, Estela Fernandez-Valenzuela, Benjamin Proudfoot, Bryan J Holler, Jose Luis Ortiz, Ishan Sharma

The small satellites of dwarf-planet size worlds in trans-Neptunian space are thought to be produced through giant impacts, and are typically observed to have bright water-ice-dominated surfaces. Here we focus on Quaoar's small primary satellite, Weywot. We build on previous work by re-analyzing the June 2023 stellar occultation by Weywot using results from 11 orbits of HST imaging with the Wide Field Camera 3. Weywot's rotational lightcurve was constrained along with its independent photometric…

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physics.chem-phastro-ph.GA2026年10月8日

Gas-phase chemistry of $\mathrm{C}_3\mathrm{H}_3^+$: a key building block for carbon mass growth in space

Corentin Rossi, Jean-Christophe Loison, Anne P. Rasmussen, Roland Thissen, Nandana Pattathadathil, Christian Alcaraz, Ugo Jacovella

The gas-phase chemistry of $\mathrm{C}_3\mathrm{H}_3^+$ plays a central role in the growth of carbonaceous species across a wide range of environments, from combustion systems to interstellar media. However, the presence of multiple isomers, primarily the linear propargyl cation and the cyclic cyclopropenyl cation, has so far prevented the determination of reliable isomer-specific reaction kinetics. In this work, we combine tunable vacuum-ultraviolet (VUV) photoionization with controlled ion--mo…

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astro-ph.SR2026年10月8日

Magnetic flux cancellation in a 3D magnetohydrodynamic simulation of an emerging flux tube with a non-uniform twist

V. Agalianou, S. Patsourakos, V. Archontis

Flux emergence is often accompanied by flux cancellation, which may drive dynamic phenomena in the solar atmosphere. We studied magnetic flux cancellation in a three-dimensional resistive magnetohydrodynamic (MHD) simulation of an emerging flux tube with a non-uniform twist profile. We solved time-dependent resistive MHD equations to model flux emergence into a magnetised background atmosphere. We identified several cancellation sites, estimated their cancellation rates, and examined the magneti…

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gr-qcastro-ph.IM2026年10月8日

Testing General Relativity with Binary Lens Microlensing Events

Xinyang Jin, Shuo Cao, Xuanni Chen, Yalong Nan, Xuchen Tai, Shuxun Tian

Einstein's General Relativity (GR), which has been precisely tested on galaxy and solar system scales, is still poorly constrained in extremely weak gravitational fields (with dimensionless Newtonian potentials of $Φ\sim 10^{-8}$). In this Letter, we propose a new method to probe such a weak-field regime of gravity and measure the spatial curvature generated per unit mass. Specifically, binary microlensing events provide a laboratory to measure the parameterized post-Newtonian (PPN) parameter ($…

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astro-ph.HE2026年10月8日

From GeV to PeV: Orbital Modulation and Wind-Regulated Ultrahigh-energy Emission in Cygnus~X-3

Su-Yu Wan, Ruo-Yu Liu, Xing-Fu Zhang, Dmitriy Khangulyan

Recent LHAASO observations reveal ultrahigh-energy (UHE) gamma-ray emission from Cygnus~X-3 with evidence for orbital modulation, providing a rare opportunity to study particle acceleration and transport on binary scales. We develop a common binary--jet model that jointly explains the contemporaneous GeV--PeV spectra and orbital light curves. The GeV emission is produced by anisotropic inverse-Compton scattering of stellar photons by relativistic electrons, while multi-PeV protons escaping from…

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