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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.SRastro-ph.EPastro-ph.GA

A chemo-dynamical search for planet-candidate hosts of possible extragalactic origin

Sun Tiancheng, Chen Xunzhou, Xiang Maosheng, Zhou Jianzhao, Lu Zixuan

To date, all known exoplanetary systems have been identified around stars currently residing in the Milky Way, whereas planets formed in external galaxies remain largely unexplored. Such systems would offer a unique probe of planet formation in galactic environments distinct from the Milky Way. We combine a literature-compiled sample of Kepler, K2, and TESS planet-candidate host stars with Gaia DR3 astrometry and radial velocities, and incorporate metallicities and [Mg/Fe] abundances from the LA…

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astro-ph.IM

Enhancing the performance and capabilities of the MIRI instrument on JWST

S. Kendrew, M. Engesser, K. Rowlands, A. Noriega-Crespo, M. Decleir, H. Diamond-Lowe, M. Regan, J. Aguilar et al.

MIRI, the Mid-Infrared Instrument on the James Webb Space Telescope, is the only instrument sensitive to wavelengths longward of 5 um on the observatory. In this regime, MIRI brings order-of-magnitude improvements over past instruments and missions in a wavelength range that is challenging or impossible to access from the ground. As such, MIRI occupies a unique parameter space, offering unparalleled capabilities in all areas of astrophysics, from the Solar System to the most distant galaxies in…

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physics.ao-phastro-ph.EPphysics.geo-phphysics.space-ph

Altitude-Dependent Near-Source Spectral Filtering of Meteor Infrasound Above 80 km and Consequences for Period-Based Energy Estimates

Elizabeth A. Silber, Igor P. Chunchuzov, Oleg E. Popov, Sergey N. Kulichkov

Infrasound signal period is widely used as a proxy for source energy in bolide studies, but the reliability of period-yield relations for small, high-altitude regional meteors has not been systematically evaluated. We analyze 90 infrasound detections from well-constrained regional meteoroid events (source altitudes 20-111 km, ranges 47-268 km) and demonstrate a strong, monotonic decrease in receiver dominant frequency with increasing source altitude (Spearman r_{s} = -0.629, p = 3.3 x 10^11). No…

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astro-ph.IMphysics.ins-det

CCAT: a two-octave 1.024 GHz KID readout featuring an overlap-channel polyphase synthesis filter bank on RFSoC

Ruixuan, Xie, Adrian K. Sinclair, James Burgoyne, Maxwell Chapman, Scott Chapman, Steve K. Choi, Anthony I. Huber et al.

Next-generation submillimeter instruments require gigahertz-scale readout bandwidths to support the growing detector counts of large microwave kinetic inductance detector (KID) arrays. Designed to meet the readout bandwidth and tone-capacity requirements of the CCAT Prime-Cam 850 GHz and 410 GHz instrument modules, we developed our second-generation (Gen2) KID readout system on a Xilinx ZCU111 radio frequency system-on-chip (RFSoC), based on a parallelized overlap-channel polyphase synthesis fil…

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astro-ph.GA

Energy Partitioning in Dust-catalyzed $\mathrm{H_2}$ and HD Formation Revealed by Molecular Simulations Considering Nuclear Quantum Effects

Xiaolong Yang, Lile Wang, Di Li, Shenzhen Xu

Molecular hydrogen formation on interstellar dust grains is a key surface process in the interstellar medium, but the redistribution of the recombination energy between the substrate and the nascent molecule remains poorly understood. Here, we use ring-polymer molecular dynamics (RPMD) with a machine-learning force field to investigate energy partitioning during $\mathrm{H_2}$ and $\mathrm{HD}$ formation on graphene at $T=25, 50$ and $100 \mathrm{K}$. We focus on the chemisorbed-H recombination…

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astro-ph.HE

Time-dependent multi-energy neutrino emission from symbiotic recurrent novae: the role of accretion disks

Rui Xu, Yudong Cui, Yihan Shi, Lili Yang

Symbiotic recurrent novae provide a unique laboratory for studying thermonuclear explosions, shock evolution, and nonthermal particle acceleration in dense circumstellar environments. In this work, we develop a time-dependent, multi-energy framework to describe neutrino emission from such systems, consistently incorporating both MeV neutrinos produced during thermonuclear runaway and GeV neutrinos generated through hadronic interactions in nova-driven shocks. Using RS Oph as a benchmark source,…

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astro-ph.SR

H-$α$ Integral Carrington Synoptic Maps Produced by NSO/NISP

K. J. Shuman, L. Bertello, O. Burtseva, A. A. Pevtsov

Monitoring long-term chromospheric activity and large-scale solar structures like filaments and plages is critical for understanding solar magnetic cycles and predicting space-weather events. While photospheric magnetic fields are routinely mapped, a consistent, global reference for chromospheric structures has been absent from H-$α$ observations. This technical report provides a comprehensive description of the methodology used to construct the NSF Global Oscillations Network Group (GONG) H-$α$…

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astro-ph.IM

Performance Analysis of the Asgard/NOTT Nulling Interferometer: Optimizing Observing Modes for High-contrast Detection

J. P. Scott, S. Ertela, T. A. Stuber, D. Defr`ere, R. Laugier, J. C. Augereau, P. Chingaipe, G. Garreau et al.

We evaluate the performance of three beam-combination schemes, single-Bracewell, asymmetric dual-Bracewell, and symmetric dual-Bracewell, for the forthcoming Asgard/NOTT nulling interferometer at the Very Large Telescope Interferometer. Utilizing the SCIFYsim end-to-end simulator, we assess the instrument's performance by deriving the precision of calibrated null measurements as a function of stellar magnitude and simulating observations of varying hot exozodiacal dust (HEZD) distributions and a…

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astro-ph.IM

Performance Analysis of the Asgard/NOTT Nulling Interferometer: Optimizing Observing Modes for High-contrast Detection

J. P. Scott, S. Ertel, T. A. Stuber, D. Defrère, R. Laugier, J. C. Augereau, P. Chingaipe, G. Garreau et al.

We evaluate the performance of three beam-combination schemes, single-Bracewell, asymmetric dual-Bracewell, and symmetric dual-Bracewell, for the forthcoming Asgard/NOTT nulling interferometer at the Very Large Telescope Interferometer. Utilizing the SCIFYsim end-to-end simulator, we assess the instrument's performance by deriving the precision of calibrated null measurements as a function of stellar magnitude and simulating observations of varying hot exozodiacal dust (HEZD) distributions and a…

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astro-ph.GA

The CMZ Asymmetries: Feeding or Feedback?

John Bally

Three-fourths of the dense gas and dust in the CMZ is located at positive longitudes and positive radial velocities. The majority of compact 24 micrometer wavelength sources are at negative longitudes. These two asymmetries indicate either a recent asymmetric injection of gas along the bar dust lanes, or that most of the molecular gas is contained in a small number of massive, gravitationally bound clouds, or a major feedback episode which dissociated an entire sector of the CMZ's dense gas.

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astro-ph.IM

MORFEO control strategy

Guido Agapito, Lorenzo Busoni, Cédric Plantet, Giulia Carlà, Alfio Puglisi, Jean-Pierre Véran, Marco Falotico, Gabriele Umbriaco et al.

The ESO Extremely Large Telescope (ELT) will offer unprecedented sensitivity and resolution in the near-infrared, marking a new era for ground-based astronomy. Among its key imaging instruments is MORFEO coupled with MICADO. MORFEO (Multi-conjugate adaptive Optics Relay For ELT Observations), formerly known as MAORY, is the largest astronomical adaptive optics system ever designed. It features 12 wavefront sensors and three deformable mirrors, for a total of over 20,000 subapertures and over 6,0…

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astro-ph.GA

Old Disks Die Hard: How Does AGN Feedback Suppress Disk Formation in Milky Way Mass Galaxies?

Patricia Fofie, James S. Bullock, Sarah Wellons, Jorge Moreno, Francisco J. Mercado, Andrew Wetzel

The connection between a galaxy's visual shape and its star formation rate is one of the oldest established trends in galaxy evolution, yet the origin of this trend remains unsettled. We analyze two Milky-Way mass halos simulated with FIRE-2 galaxy formation physics, each run without AGN and with up to three implementations of AGN feedback. We use them to study how and why AGN star formation suppression affects morphological evolution over cosmic time. Both runs without AGN feedback produce prom…

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astro-ph.HE

The second Arcminute Microkelvin Imager -- Large Array Gamma-ray burst radio afterglow catalog

L. Rhodes, D. Ibrahim, N. Sqalli, G. E. Anderson, R. Fender, A. J. van der Horst, J. S. Bright, A. K. Hughes et al.

Radio observations of gamma-ray burst afterglows provide insight in to the different emitting regions within the jet, its hydrodynamics and burst environment. In this paper, we present the second iteration of the Arcminute Microkelvin Imager - Large Array (AMI-LA) Gamma-ray burst (GRB) radio afterglow catalog. The catalog consists of 1035 observations of 210 bursts. Our observations range from 0.04 to 900days post-burst. We detect radio emission associated with 19 events with flux densities span…

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astro-ph.HE

High-Energy Neutrinos from Supernova Shock Breakouts in Circumstellar Media: Light Curves, Spectra, and Contribution to the Extragalactic Neutrino Background

Tal Wasserman, Eli Waxman, Kohta Murase

Enhanced mass loss from core-collapse supernova (SN) progenitors shortly before explosion appears to be common, creating a compact, optically thick circumstellar medium (CSM) at $\sim10^{14}-10^{15}$ cm. We derive an analytic description of the light curves and spectra of high-energy neutrinos emitted by nonrelativistic SN shock breakouts through such CSM, as a function of shock velocity and CSM parameters, accounting for the evolution of the hydrodynamic structure and the electromagnetic (EM) s…

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astro-ph.GAastro-ph.CO

Abundant Heavy Black Hole Seeds from Moderate Lyman-Werner Radiation

Ryan Hazlett, Eli Visbal, Greg L. Bryan, Mihir Kulkarni

The existence of high-redshift quasars may indicate that massive black hole seeds formed via supermassive Population III stars in atomic-cooling halos with large gas inflow rates; however, the dependence of this process on halo assembly rate and radiative background remains poorly constrained. We present a large suite of 65 high-resolution cosmological zoom-in simulations of 15 pristine halos spanning a wide range of Lyman-Werner radiation backgrounds and halo assembly histories. We introduce a…

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astro-ph.HEastro-ph.GAastro-ph.SR

No Evidence for Nearby Circumstellar Material in the Type Ia Supernova 2025rbs

Aravind P. Ravi, Griffin Hosseinzadeh, Stefano Valenti, Saurabh W. Jha, Jennifer Andrews, David J. Sand, Benjamin J. Fulton, William D. Vacca et al.

We present a high-resolution spectral time series of the Type Ia supernova (SN) 2025rbs discovered in the nearby galaxy NGC 7331. The Automated Planet Finder (APF) at Lick Observatory and the MAROON-X/IGRINS-2 at Gemini North were used to obtain echelle spectra between -5 and 15 days with respect to the epoch of maximum light. Several unsaturated NaID absorption components along the line of sight are identified, but there is no evidence of time variance in any of them. We measure the equivalent…

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astro-ph.SRastro-ph.HE

Radio Properties of RS Canum Venaticorum Variables in VLASS and RACS

Suhasini S. Rao, Gregory R. Sivakoff, Craig O. Heinke, Swetha Arumugam, Dougal Dobie, Laura Driessen, David L. Kaplan, Emil Lenc et al.

We performed a systematic search for radio emission from RS Canum Venaticorum (RS CVn) binaries, selected from the International Variable Star Index (VSX) catalog, in the Very Large Array Sky Survey (VLASS; three epochs) and Rapid ASKAP Continuum Survey (RACS; two epochs) data. We detected 108 candidate radio-emitting RS CVn in at least one epoch. Several of these systems rank among the most radio-luminous RS CVn binaries reported to date. The radio and X-ray luminosities, obtained from cross-ma…

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astro-ph.HE

Observational Constraints on Horizonless Compact Objects from Thermal Emission in AGNs

Ekin Oran, Avery Broderick, Kiana Salehi

The Swift Burst Alert Telescope Active Galactic Nuclei Spectroscopic Survey (BASS DR2) provides one of the largest and most complete samples of bright, local (z < 0.1) active galactic nuclei (AGNs) with high-quality spectroscopic measurements. These sources are typically interpreted within the framework of Kerr black holes; however, a wide range of horizonless compact-object scenarios-including naked singularities, black hole mimickers, and other exotic compact objects-have been proposed as alte…

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astro-ph.HEastro-ph.COastro-ph.GA

A binary black hole merger rate comparison within the same metallicity - star formation rate framework

Lumen Boco, Michele Bosi, Cecilia Sgalletta, Amedeo Romagnolo, Michela Mapelli

Recent studies have suggested that binary population synthesis models, when coupled with observationally based, metallicity-dependent star formation rate density, overpredict the observed local binary black hole (BBH) merger rate density. The significance of this tension might vary depending on the specific code and parameters adopted. Thus, a more extensive exploration of the parameter space is required. In this work, we perform such an extended analysis by considering BBH merger efficiencies c…

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hep-thastro-ph.HEgr-qc

Quasinormal modes as exterior probes of black hole interiors in our Universe

Sašo Grozdanov, Vita Movrin, Samuel Valach

We consider a scenario in which a black hole is enclosed in a reflecting timelike cavity and linearly perturbed. For the resulting quasinormal spectra of gravitational, electromagnetic, and other perturbations, in conjunction with our arXiv:2606.11297, we establish a thermal product formula and derive a universal asymptotic expression for high quasinormal overtones. Both results hold in asymptotically flat, de Sitter, and Anti-de Sitter spacetimes (known previously). This spectral signature dire…

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astro-ph.HEgr-qc

Explosions from Rotating Very Massive Star Collapses to Black Holes: Effects of Nuclear Burning

Sho Fujibayashi, Alan Tsz-Lok Lam, Yuichiro Sekiguchi, Masaru Shibata

We investigate the collapse of rotating very massive and supermassive stellar cores using numerical relativity simulations including an alpha-chain nuclear reaction network and neutrino cooling. Our main survey focuses on newly constructed models with initial core masses of $2 \times {10}^{3}-5\times 10^4M_\odot$. The collapse is triggered either by pair instability in lower-mass cores or by general-relativistic instability in higher-mass cores. We find that higher-mass cores undergo a nearly ho…

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astro-ph.EP

Effects of Pebble Accretion Isolation Mass on Observable Exoplanet Properties

Lucas Brefka, Rebekah I. Dawson, Mariah G. MacDonald, Phoebe Sandhaus, Eric B. Ford

The Kepler Mission has discovered a plethora of planetary systems with super-Earth sized planets. These systems exhibit many properties, from widely-spaced planets with non-negligible eccentricities and inclinations, to tightly-spaced, coplanar, and nearly circular multi-planet systems. The observable properties of these systems, such as planet-planet spacings, multiplicity and orbital morphology, can be strongly influenced by the initial conditions of formation. These conditions affect the earl…

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astro-ph.GAastro-ph.HE

Orbital Migration of Interacting Stellar Mass Black Holes in Disks around Supermassive Black Holes. III. Mass Distribution of Hierarchical Mergers

Katherine L. Gonglewski, Amy Secunda, Mordecai-Mark Mac Low, K. E. Saavik Ford, Barry McKernan, Fabian R. N. Schneider

Active galactic nucleus (AGN) disks are a promising location for the formation of binary black holes (BBHs) that will merge on relatively short timescales and be detected by LIGO-Virgo-KAGRA (LVK). To compare the mass function (MF) of black holes (BHs) undergoing hierarchical mergers in AGN disks to the inferred MFs from LVK observations, we perform 360 simulations with an N-body code augmented to include an analytic model for migration torques and other gas forces. We focus on the region surrou…

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astro-ph.IMastro-ph.HE

Laser Metrology for Precision Alignment of Transmission Gratings in the REDSoX Soft X-ray Polarimeter

Swati Ravi, Alan Garner, Jill Juneau, F. Elio Angile, Ralf K. Heilmann, Herman L. Marshall, Sarah N. T. Heine

The Rocket Experiment Demonstration of a Soft X-ray Polarimeter (REDSoX) is a NASA sounding-rocket mission designed to perform the first astrophysical spectropolarimetry in the 0.2-0.4 keV energy band. The instrument uses critical-angle transmission (CAT) gratings to disperse incident X-rays onto laterally graded multilayer (LGML) mirrors, requiring 48 individual gratings to be co-aligned to within 6 arcminutes in yaw, pitch, and roll. To support the systematic assembly of the grating array, we…

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astro-ph.EPastro-ph.SR

The sensitivity of TESS to transiting planets in TOIs with close-in stellar companions

Colin Littlefield, Kathryn V. Lester, David R. Ciardi, Steve B. Howell

High resolution imaging with optical speckle interferometry has revealed that many transiting exoplanet host stars possess close-in stellar companions. The objective of this study is to quantify how the presence of these companions impacts the ability of TESS to detect the transits of small planets. We accomplish this by examining 2052 TESS Objects of Interest (TOIs) that appear to be single-star systems based on speckle interferometric observations as well as 188 TOIs in unresolved ($< 1.2\arcs…

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astro-ph.IM

Numerical Model Simulation of the Carruthers GCI Images

Heather Filippini, Alex Zhang, Evan Widloski, Jason McPhate, Lara Waldrop, Thomas Immel, John Clarke, Pratik Joshi et al.

The Carruthers Geocorona Observatory, launched in September 2025, is NASA's first mission devoted to investigating the fundamental nature of Earth's exosphere from its distant vantage in halo orbit around the Earth-Sun Lagrange (L1) point. Its primary payload, the GeoCoronal Imager, consists of two coaligned photometric imagers that measure the radiance of ultraviolet emission at 121.6 nm (Lyman-$α$, or Ly-$α$) from exospheric hydrogen atoms simultaneously at wide and narrow fields of view. In o…

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astro-ph.EP

No Helium Detected in LHS 1140 b from Four JWST NIRISS/SOSS Transits

Katherine A. Bennett, Carlos Gascón, Jacob Lustig-Yaeger, Guangwei Fu, David K. Sing, Kevin B. Stevenson, Jonathan Brande, Munazza K. Alam et al.

In the effort to determine which low-mass exoplanets have atmospheres, LHS 1140 b remains one of the most favorable targets. Its large size (5.6 $\rm M_{\oplus}$ and 1.7 $\rm R_{\oplus}$) and relatively long orbital period (24.7 days) imply an atmosphere may be likely, and notably, recent interior models favor either a hydrogen-dominated "mini-Neptune" or a "water world" over a true terrestrial planet. Another possibility is that it has a helium-rich atmosphere. This hypothesis is supported by r…

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astro-ph.EP

Strict Limits on Helium Absorption from LHS 1140 b from Four JWST NIRISS Transits

Michael Radica

Orbiting in the habitable zone of its host star, the 1.7 $R_\oplus$, 5.6 $M_\oplus$ planet LHS 1140 b is a target of great interest. Recently Cherubim et al. (2026) published a detection of metastable He escaping from the atmosphere of LHS 1140 b, simultaneously providing the first concrete inference of an atmosphere on this planet and indicating that the atmosphere is He-rich and H-poor as would be expected due to Gyrs of fractionated mass loss. In this work, we analyze four archival transits o…

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astro-ph.IM

JWST MIRI Medium Resolution Spectrometer Point Fixed Pattern Corrections: Cleaner and Higher Signal-to-Noise Spectra of Point Sources

Karl D. Gordon, David R. Law

The JWST Mid-Infrared Instrument Medium Resolution Spectrometer provides the capability to obtain spectra from 5-28 micron. The JWST data reduction pipeline removes the majority but not all of the instrument artifacts and the signal-to-noise (S/N) of the resulting spectra are limited by fixed pattern noise. Building on previous work, Point Fixed Pattern Corrections (PFPCs) are constructed using observations of O, A, and G dwarf flux calibration stars and asteroids taken using the default four po…

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astro-ph.SRastro-ph.HEnucl-thphysics.plasm-ph

The Production of Electron-Capture Elements in Thermonuclear Supernovae: Theory vs. Observations

S. Shiber, P. Hoeflich, T. Mera, E. Fereidouni, Z. Levy, D. Maci, C. Ashall, K. Medler et al.

Type Ia supernovae (SNe Ia) explosively destroy carbon-oxygen white dwarfs (WDs) in multiple stellar systems. They produce approximately 50% of the iron-group elements in the Universe, synthesize electron-capture (EC) elements, drive nuclear physics experiments, and underpin high-precision cosmology. To first order, the outcome is governed by nuclear physics, a property often described as stellar amnesia. Recently, this stellar amnesia has begun to be broken by the nearly universal detection of…

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