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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

Identifying and Distinguishing Quenching Galaxies with Spatially Resolved Star Formation in the Hubble Frontier Fields

Cameron Lawlor-Forsyth, Michael L. Balogh, Sean L. McGee, Gregory H. Rudnick

We investigate the nature and prevalence of different quenching signatures for 1437 galaxies with $M_{*} \geqslant 10^{8}~\mathrm{M}_{\odot}$ and $\text{SFR} \geqslant 10^{-3}~M_{\odot}~\text{yr}^{-1}$ in the Hubble Frontier Fields through spatially resolved spectral energy distribution fitting with \texttt{FAST++}. We use the morphological metrics previously presented in our series of investigations to quantify the distribution of star formation, and use a $k$-nearest neighbors algorithm to cla…

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gr-qcastro-ph.HEastro-ph.IM

A story about a tipsy kangaroo: Reversible jump MCMC for model selection in the analysis of gravitational-wave signals from the coalescence of compact objects

Anna Puecher, Tim Dietrich, Hauke Koehn, Jonathan Gair, Gregory Ashton, Luca Negri, Anuradha Samajdar

Bayesian inference is commonly employed in the analysis of gravitational-wave signals not only to estimate the source parameters, but also for model selection. The latter provides insight into the physics of the source and has the potential to inform the direction for future model development. Although model comparison is usually performed by analyzing the data separately with different models and comparing the obtained Bayesian evidences, an alternative approach consists in sampling directly ov…

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astro-ph.SR

CO second overtone line variability in three carbon-rich early post-AGB stage stars

Kārlis Puķītis

Near-infrared CO molecular lines are suggested to be linked with dynamic processes in post-AGB stars; however, they have not been investigated at high spectral resolution. CO second overtone line variability in the H-band is presented for the cool carbon-rich post-AGB stars IRAS 22272+5435, IRAS Z02229+6208, and IRAS 20000+3239. CO features are observed to change intensity, shape, and radial velocity as well as switch between emission and absorption during the pulsation cycle. At all times, the…

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astro-ph.GA

ALMA CO-CAVITY II. Resolved Scaling Relations in Void Galaxies

S. B. De Daniloff, D. Espada, S. Duarte Puertas, Y. K. González-Koda, G. Torres-Ríos, S. F. Sánchez, R. García-Benito, S. Verley et al.

Scaling relations involving star formation rates (SFRs), molecular gas mass, and stellar mass are key to understand galaxy evolution, and have previously been explored at resolved scales. However, they have not been examined with particular emphasis on the large-scale environments (LSEs). In this work, we study the resolved Schmidt-Kennicutt relation (rSK), molecular gas main sequence (rMGMS) and star-forming main sequence (rSFMS) from a sample of 41 void galaxies (VGs) residing in the least den…

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astro-ph.HEhep-ph

Light Antinuclei Coalescence: Femtoscopic Constraints via Neural-Flow Surrogates

M. Korwieser, L. Fabbietti, B. Hashemi, L. Heinrich, M. Mahlein, D. L. Mihaylov, C. S. Zeyn

Precise predictions of cosmic-ray antinuclei fluxes, a prime dark matter signature, are limited by the lack of data constraining production rates of antinuclei. We mitigate this bottleneck with a fast, differentiable normalizing-flow surrogate for the femtoscopic source model (CECA), fit to 49 ALICE proton-proton correlation functions, and extrapolated via scaling laws to the low-multiplicity domain relevant for cosmic rays. The surrogate reproduces CECA with sub-percent emulation fidelity, yiel…

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astro-ph.IMastro-ph.CO

Atmosphere mitigation in CMB observations using multi-frequency time-domain component separation

Julien Tang, Shamik Ghosh, Jacques Delabrouille, John C. Groh, Oliver Jeong, Reijo Keskitalo, Theodore Kisner

CMB observations from ground-based observatories are limited in sensitivity by the fluctuating emission from the Earth's atmosphere, mostly due to water vapor inhomogeneities. Even in atmospheric windows, this spurious signal remains the major source of contamination of the data. Traditional mitigation techniques include low-frequency filtering, or for polarization measurements specifically, modulation with a rotating half-wave plate. The first method filters out a significant fraction of the ta…

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astro-ph.IMstat.AP

Modeling Dependence Structures in Astronomical Multi-Band Time Series Data via Multi-Output Gaussian Processes

Samata Das, Lishan Shi, Yasaman Hamayouni, Hyungsuk Tak, Jong-Hak Woo

Modern astronomical time-domain surveys routinely collect multi-band light curves that provide complementary information about the physical processes governing source variability. Gaussian processes (GPs) provide a flexible probabilistic framework for modeling irregularly sampled and noisy time-series data. While considerable attention has been devoted to developing covariance kernels for individual time series, comparatively less attention has been paid to the statistical representation of depe…

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astro-ph.EP

Experimental Measurements of Benzene Ice Critical Saturation Ratios on Titan Tholins and Impact on the Microphysical Modeling of Titan's South Polar Benzene Cloud

David Dubois, Erika Barth, Laura T. Iraci, Ella Sciamma-O'Brien, Farid Salama, Sandrine Vinatier

The Cassini Composite Infrared Spectrometer (CIRS) revealed the presence of a benzene (C6H6) ice cloud in Titan's autumn south polar stratosphere, following the northern spring equinox in August 2009. This event increased the mixing ratio of benzene and raised the cloud top altitude. We present here new experimental measurements of the critical saturation (Scrit) of pure C6H6 ice at low temperature (from 13.8 at 138 K to 3.3 at 157 K), representative of Titan's atmospheric temperatures, when dep…

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astro-ph.HEastro-ph.COgr-qchep-phhep-th

Ultra-High-Energy Particle Production in Binary Mergers Endowed with Magnetic Fields

Carlos H. Coimbra-Araujo, Rita C. Anjos, Jonas P. Pereira, Jaziel G. Coelho

We study the production of ultra-high-energy particles via the Bañados--Silk--West (BSW) mechanism in the pre-merger phase of binary systems detected by LIGO-Virgo-KAGRA. By solving the geodesic equations for charged particles in magnetized Kerr spacetime with fields of $B \sim 10^{12}$--$10^{14}$~G, we demonstrate that collisions near the horizon can achieve center-of-mass energies $E_{\mathrm{cm}} \sim 10^{18}$-- $10^{20}$~eV, placing them firmly in the ultra-high-energy cosmic-ray (UHECR) ran…

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astro-ph.HE

Importance and Science Outcomes from the first XSPECT/XPoSat Workshop

Anuj Nandi, Rwitika Chatterjee, V. P. Shyam Prakash, Ankur Kushwaha, M. C. Ramadevi, Kiran M. Jayasurya, Vivek K. Agrawal, M. Varun et al.

This paper summarizes the science outcomes of the first Workshop on Data Analysis using observations from the XSPECT payload onboard the XPoSat, which brought together early-career researchers and experts to explore the instrument's scientific capabilities through lectures and hands-on analyses. Participants performed end-to-end data analysis, including calibration, spectral modeling, and timing studies, on seven sources comprising Neutron Star Low-Mass X-ray Binaries, pulsars, and Black Hole X-…

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astro-ph.HEastro-ph.SR

Rapid Orbital Decay of Supersoft X-Ray Source WX Cen: a Surrounding Circumbinary Disk

Zhi-Qiang Liu, Wei-Min Liu, Wen-Cong Chen

WX Cen is most likely a candidate of compact binary supersoft X-ray sources, which consists of a white dwarf (WD) and a donor star that fills the Roche lobe. Recently, this source was detected to be experiencing a rapid orbital decay at a rate of $\dot{P} =-(4.4\pm0.4)\times10^{-7}~ \rm days~\rm{yr}^{-1}$. According to the mass function and optical eclipses, the donor-star mass can be constrained to be $0.41-0.44$, $0.47-0.50$, and $0.55-0.59~M_\odot$ when the WD mass is $0.7$, $0.9$, and $1.2~M…

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astro-ph.EPastro-ph.SR

Magnetohydrodynamical opening of dust traps in protoplanetary disks

Sergey Khaibrakhmanov, Vitaly Akimkin

Observed ring-like structures in protoplanetary disks are often interpreted as local pressure maxima, which induce efficient dust concentration. We revisit this paradigm, considering the effect of the large-scale magnetic field stresses on the gas rotation speed. Our simulations show that the magnetic field can be dynamically strong and cause $1-2$% deviation from the Keplerian rotation at the periphery of a typical turbulent disk with dust grains of size $> 1\,μ$m. This effect increases the inw…

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astro-ph.IMastro-ph.EP

Detecting habitable exoplanet atmospheres with LIFE, the Large Interferometer for Exoplanets

Sarah Rugheimer, Aiden Weatherbee, James Fecanin, Alistair Glasse, Paul Rimmer, Eleonora Alei, Esther Wang, Marrick Braam et al.

A key goal of astronomers with the next generation telescopes is to detect signs of life in exoplanet atmospheres. NASA's next flagship is the Habitable Worlds Observatory (HWO). In the context of ESA's Voyage 2050 program, the Senior Committee report prioritises detecting habitable exoplanet atmospheres in the mid-IR. The most suited mission for this is the Large Interferometer for Exoplanets (LIFE) which can detect an even wider range of biosignatures than HWO and at lower concentrations. LIFE…

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astro-ph.HE

Spirited Away: Advective Loss of Cosmic Rays into the Milky Way's Circumgalactic Medium Explains the Large Magellanic Cloud's Low Gamma-ray Luminosity

Taaseen Islam, Hilay Shah, Mark R. Krumholz, Roland Crocker

Models of galactic-scale cosmic ray production and transport have successfully reproduced the radio and $γ$-ray spectra of many galaxies; however, one notable exception is the Large Magellanic Cloud (LMC), where models that successfully fit other galaxies consistently overestimate its $γ$-ray flux. Here we investigate this discrepancy by applying the CRIPTIC cosmic ray transport code to recent magnetohydrodynamic simulations of the LMC's interactions with the Milky Way circumgalactic medium that…

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astro-ph.SRphysics.plasm-ph

Collisionless stationary states of a stratified plasma in an expanding magnetic tube with stochastic heating

Luca Barbieri, Pascal Démoulin, Daniel Verscharen

We investigate the collisionless kinetic structure of the upper solar atmosphere in the presence of an expanding magnetic field. We consider a stationary two-component plasma confined within an expanding magnetic flux tube and subject to gravity, self-electrostatic interactions, the Pannekoek-Rosseland electric field, and magnetic moment conservation. Starting from the Vlasov equation, we derive fully analytical expressions for the particle distribution functions, density profiles, and the paral…

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astro-ph.IM

PROVIDENCE: a ground station for space observation

P. -L. Mayeur, J. -F. Sauvage, T. Fusco, N. Védrenne, C. Petit, D. Barbon-Dubosc, G. Leplat, G. Guerrin et al.

PROVIDENCE is an ONERA-led project to install a new-generation optical ground station at the Haute-Provence Observatory (OHP) in South of France. Built around a 2.5-meter aperture, the station addresses five core science cases: space domain awareness, astronomy, laser activities and communications, atmospheric characterization, and instrumental prototyping. The project is organized into three parallel subprojects covering the telescope (Providence T), the building (Providence B), and the instrum…

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astro-ph.SRastro-ph.GAastro-ph.IMphysics.hist-ph

Echoes of Star Stories: Integrating Indigenous narratives into modern stellar astrophysics

Dionysios Gakis

Indigenous narratives have long preserved observations of celestial phenomena, offering insights that resonate with modern astrophysical research. Deeply embedded in cultural traditions, these stories describe events such as stellar variability, supernovae, eclipses, and planetary alignments. Indigenous communities have also used the stars for navigation and calendar systems, reflecting a sophisticated understanding of celestial patterns. These narratives not only complement historical records b…

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astro-ph.IM

HARMONI at ELT: optical design of the spectrograph sub-system

Eduard Muslimov, Matthias Teczaa Edgar Castillo-Dominguez, James Kariuki, Liam Bolanda, Miriam Cisneros-Gonzalez, Kieran McCall, Sophie Paszynska

HARMONI is an adaptive optics assisted, near infrared integral field spectrograph for the European Extremely Large Telescope. It covers a spectral range from 750 nm to 2450 nm with resolving powers from 3000 to 7000 and spatial sampling of 25 mas and 6 mas. It can operate in two adaptive optics modes, SCAO and MCAO. The spectrograph represents the last optical sub-system of the HARMONI instrument optical train that disperses the light and forms a two-dimensional spectrogram on its scientific det…

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physics.opticsastro-ph.IM

Laser Remelting for Reduced Porosity on Additively Manufactured Aluminium Mirrors

Joshua West, Valentina Oyarzun, Marcell Westsik, Younes Chahid, Magdalena Kraus, Scott McPhee, William Brzozowski, Samuel Tammas-Williams et al.

Additively manufactured (AM) AlSi10Mg mirrors are fabricated through laser powder bed fusion (LPBF), allowing the use of complex geometries such as lattices and organic structures that enable high mass reduction while maintaining mechanical stiffness. Micron-sized pores that cause optical scatter may form during LPBF as a consequence of deviations from the optimal processing window, particularly from laser energy input and scan strategy. This work proposes a laser remelting strategy aimed at red…

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astro-ph.COastro-ph.GA

Contribution to the 2026 Cosmology session of the 60th Rencontres de Moriond: Galactic moments: Understanding polarized foregrounds complexity in the quest for CMB primordial $B$ modes with LiteBIRD

S. Vinzl, J. Aumont, L. Vacher, R. T. Génova-Santos, D. Adak, A. Rizzieri, for the LiteBIRD Collaboration

Accurate modeling of polarized Galactic emission has become a major challenge for current and next-generation cosmic microwave background (CMB) $B$-mode experiments. Ignoring the spectral complexity of thermal dust and Galactic synchrotron emission when integrating along the line of sight and over large sky fractions inevitably leads to biases in CMB polarization analyses. In this work, we review how the future LiteBIRD satellite, which will benefit from an increased number of bands and sensitiv…

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physics.atom-phastro-ph.SRphysics.plasm-ph

Plasma screening and configuration interaction effects induced large enhancement on L-shell photoionization cross sections and opacity

Fuyang Zhou, Shengbo Niu, Simei Lu, Chuangying Li, Xiang Gao, Yong Wu, Yizhi Qu, Jianguo Wang et al.

An opacity model that incorporates improved treatments of both plasma screening and configuration interaction (CI) effects is proposed, and a 25-30% enhancement on the iron L-shell opacity is predicted at solar interior temperatures. It is originated from the plasma screening induced 14-17% enhancement on the photoionization cross sections and the CI induced 10-20% enhancement on photoexcitation and photoionization cross sections for open L-shell ions. These explain the long-standing discrepancy…

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astro-ph.GA

High-Resolution [CI] $({^3\mathrm{P}_2}\rightarrow{^3\mathrm{P}_1})$ and CO $(J=7\rightarrow6)$ Observations of Circumnuclear Disks in Nearby Seyfert Galaxies

Dragan Salak, Suphakorn Suphapolthaworn, Yusuke Miyamoto, Naomasa Nakai, Masumichi Seta, Kazuo Sorai

We present [CI] $({^3\mathrm{P}_2}\mathrm{-}{^3\mathrm{P}_1})$, CO $(J=7\mathrm{-}6)$, and 800-GHz continuum observations of the circumnuclear disks (CNDs) in the Seyfert galaxies NGC 613 and NGC 1808 with the Atacama Large Millimeter/submillimeter Array. The images reveal the distributions of neutral gas and dust in nearby galaxy nuclei at a resolution of $0.2''$ (10 pc) which is unprecedented at these frequencies. Both lines and continuum exhibit peaks at the position of molecular tori. The ma…

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astro-ph.SR

Comparative 3D Asymmetric Expansion and Angular Widths Evolution of Fast and Slow Coronal Mass Ejections

Anjali Agarwal, Wageesh Mishra, Jie Zhang, Soumyaranjan Khuntia, Manuela Temmer

The radial and lateral dimensions of coronal mass ejections (CMEs) influence their duration and probability of encounter at Earth. These properties are linked to the expansion speed of CMEs in different radial and lateral directions; however, most earlier studies modeled CME evolution using a projected full ice-cream cone geometry, which does not distinguish between radial and lateral expansion. Our study investigates the asymmetric expansion (relative radial and lateral components) and kinemati…

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astro-ph.GAastro-ph.CO

The Stellar Mass Function of Gas-Rich Galaxies and the Underlying $M_{\rm HI}-M_{\rm star}$ Scaling Relation in the Local Universe

Tanya Tripty, Nishikanta Khandai, Saili Dutta, Khushi Sharma

We estimate the Galaxy Stellar Mass Function (GSMF) of HI gas-rich galaxies using the 100\% ALFALFA ($α$) catalog, $\sim 98\%$ of which have optical counterparts in the Sloan Digital Sky Survey (SDSS) and a subset of them have counterparts in GALEX SDSS WISE Legacy Catalogue-2(GSWLC-2). We use the mass estimates from this subset which combines UV, optical and IR bands with individual dust corrections to recalibrate optical stellar mass estimates. We use a non-parametric method to estimate the GS…

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hep-phastro-ph.HEastro-ph.SRhep-ex

MeV Electrophilic Axion-like Particles from Sun

Shao-Feng Ge, Sk Jeesun, Tao Li

This work explores the production of an MeV-scale electrophilic axion-like particles (ALPs) by utilizing the monochromatic 5.5MeV photon resulting from the nuclear fusion processes in the Sun. These 5.5MeV photons can undergo the Compton-like scattering with the ambient electrons in the solar matter to produce a substantial flux of MeV ALPs. Upon reaching the Earth, such ALPs can be detected via the same electron coupling, offering a new opportunity for the dark matter (DM) direct detection expe…

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astro-ph.IM

Infrasound Newtonian Noise Estimation at the Einstein Telescope Candidate Site Sos Enattos

Wathela Alhassan, D. Rosinska, M. Suchenek, E. Fenyvesi, T. Bulik

We investigate the seasonal variability of atmospheric infrasound and its contribution to Newtonian noise (NN) at the Sos Enattos site, a leading candidate location for the Einstein Telescope (ET). Infrasound data recorded at three stations -- SOE0 (surface), SOE1 ($-84$ m), and SOE3 ($-160$ m) -- are analyzed over multiple seasons to characterize both temporal variability and the depth dependence of the acoustic field. The amplitude spectral density (ASD) at 1 Hz exhibits a clear seasonal modul…

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astro-ph.GA

What's Missing in AGN Feedback? Lessons learnt from Magneticum, IllustrisTNG and Simba

D. T. Mazengo, P. Popesso, I. Marini, L. M. Valenzuela, N. de Isídio, V. Toptun, Mirjana Pović, Petri Väisänen et al.

Accurately balancing gas reservoirs, star formation, and feedback across cosmic time remains a central challenge for galaxy formation models in modern hydrodynamical simulations. While different feedback prescriptions reproduce selected local galaxy properties with varying success, the most pronounced discrepancies emerge in predictions for the hot gas content of dark matter halos. We examine three state-of-the-art cosmological simulations: Magneticum, IllustrisTNG, and SIMBA, which struggle to…

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astro-ph.IM

Fast Inference on Astronomical Time Series with Trans-Dimensional Flow Matching Posterior Estimation

Nina van der Meulen, Tin Hadži Veljković, Daniela Huppenkothen, Benjamin Kurt Miller, Christoph Weniger

The analysis of time series plays an important part in the study of (fast) transient events, including gamma-ray bursts, magnetar bursts, fast radio bursts, and solar flares. A common approach is to decompose the time series into pulses and study the pulse characteristics, such as location and amplitude, in order to constrain physical models of the source and its environment. However, estimating both the number and characteristics of these pulses presents a trans-dimensional inference problem th…

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astro-ph.GA

MIGHTEE: The Host-Galaxy Associated Catalogue of the Radio Sources in MIGHTEE Continuum Data Release 1

C. L. Hale, J. Hamlett, I. H. Whittam, M. J. Jarvis, M. J. Hardcastle, S. L. Jung, N. Stylianou, R. G. Varadaraj et al.

Radio continuum surveys provide samples of active galactic nuclei (AGN) and star forming galaxies (SFGs) to high redshifts, free of biases due to dust obscuration. However, radio detected sources require multi-wavelength counterparts to understand their intrinsic properties (e.g. redshift, stellar mass) and to study the evolution of star formation and AGN activity. In this work we present host galaxy counterparts for the MeerKAT International GHz Tiered Extragalactic Exploration (MIGHTEE) survey…

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astro-ph.SR

Transport of angular momentum and chemical elements by the MRI dynamo in stellar radiative zones

Laurène Jouve, François Lignières, Jérôme Guilet, Alexis Vanbesien

The question of angular momentum transport by magnetic fields has recently been revived by the detection of magnetic fields in the deep interior of red giant stars. We aim at characterizing the efficiency of the transport of angular momentum and chemical elements in a stellar radiative zone subject to the magneto-rotational instability, in situations where hydrodynamical instabilities are not triggered. We use a large set of zero-net flux shearing-box simulations modelling a portion of a stellar…

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