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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.IMastro-ph.EPastro-ph.GA

Microlensing Detection and Inference via Learned Bayes Factors

Nolan Smyth, Laurence Perreault-Levasseur, Yashar Hezaveh

We present a unified framework for gravitational microlensing event detection and parameter inference. Traditional pipelines use deterministic hard cuts on photometric statistics, systematically missing low-magnification events in the finite-source regime. We instead frame detection as Bayesian model comparison using Evidence Networks, which learn calibrated Bayes factors from binary-labeled simulations, and combine this with Neural Posterior Estimation (NPE) for amortized parameter inference. B…

astro-ph.IM

Long-term performance of the MLR-TT sensor: two-photon polymerization validation in the telescope environment

Robert J. Harris, Philipp Hottinger, Jonathan Crass, Philipp-Immanuel Dietrich, Christian Koos

We report on the long-term optical performance of a two-photon polmerized microlens ring tip-tilt sensor. The study is backed by repeated measurements over the last six years, since the sensor was first tested in the sky at the Large Binocular Telescope. The goal of the study is to assess the feasibility of the underlying technology of two-photon polymerization for future instrumentation in the realistic environments experienced at astronomical telescopes.

physics.comp-phastro-ph.EPcs.LG

Dynamical and Optimization Trade-offs of Levi--Civita Coordinates for Learned Close-Encounter Dynamics

Abhishek Shankar

Classical regularization removes the binary-collision singularity from the Kepler problem, but its value as a representation for learned Hamiltonian dynamics has not been systematically isolated. We compare Cartesian and planar Levi--Civita formulations of a perturbed Kepler system with a smooth quadrupole potential. With the perturbation supplied analytically, a Levi--Civita Hamiltonian splitting holds the maximum relative energy error near $2.1\times10^{-5}$ through eccentricity $e=0.99$, whil…

astro-ph.HEastro-ph.IM

Identifying Kilonovae in the Presence of Optical Afterglow for the Wide-Field Survey Telescope

Huan Yang, Zhengyan Liu, Liang-Duan Liu, Wen Zhao, Zigao Dai

Identifying kilonovae associated with binary neutron star mergers is often complicated by the presence of a dominant synchrotron afterglow. In this work, we evaluate the performance of the Wide-Field Survey Telescope (WFST) in identifying kilonova signals in composite afterglow-kilonova transients. Using a numerical framework based on the Fisher information matrix, we simulate $10,000$ realizations for each of two scenarios: an AT2017gfo-based template model and a physically sampled population t…

astro-ph.HE

Shock acceleration in vortex driven magnetic fields of black holes

Zaza N. Osmanov

The aim of this work is to investigate particle acceleration by shock waves in the magnetospheres of supermassive black holes, where the magnetic field is vortex-driven. For this purpose, we investigated the first-order Fermi acceleration process at relativistic shocks in the magnetospheres of supermassive black holes. In our analysis, we considered synchrotron radiation and inverse Compton scattering as the principal energy-loss mechanisms limiting the maximum attainable particle energy. We inv…

astro-ph.IM

Asgard/NOTT: Cryogenic characterization of the mid-infrared chip

G. Garreau, D. Defrère, R. Laugier, P. Chingaipe, M-A. Martinod, T. Mattheussen, K. Missiaen, J. Morren et al.

NOTT is part of the new visitor instrument suite Asgard for the Very Large Telescope Interferometer (VLTI), and the first long-baseline nulling interferometer that will be operational in the southern hemisphere. It is an L'-band (3.5-4$\,μ$m) instrument optimized for imaging hot exozodiacal dust and young giant planets orbiting around the snowline of nearby main-sequence stars. For planet imaging, the L' band has the advantage of relaxing the requirements on the star-planet contrast to $\sim 10^…

astro-ph.IM

ESO-VLT BlueMUSE instrument - Conceptual Design for Phase A

Florence Laurent, Johan Richard, Rémi Giroud, Davor Krajnović, Alexandre Jeanneau, Manuel Abreu, Angela Adamo, Théo Battrel et al.

BlueMUSE is a blue-optimised, medium spectral resolution, panoramic integral field spectrograph under development for the ESO's Very Large Telescope (VLT). The project is now entering preliminary design phase. With an optimised transmission down to 350 nm, spectral resolution of R $\sim$ 3500 on average across the wavelength range, and a large FoV (1 arcmin2), BlueMUSE will open up a new range of galactic and extragalactic science cases facilitated by its specific capabilities. BlueMUSE consists…

astro-ph.SR

Relationship of ICME Composition Signatures with Solar Activity during 2009-2025

Diyorbek Pulatov, Zavkiddin Mirtoshev, Mirabbos Mirkamalov

Coronal Mass Ejections (CMEs) are among the most energetic solar eruptions, expelling magnetized plasma from the corona into interplanetary space. Their interplanetary counterparts, known as Interplanetary Coronal Mass Ejections (ICMEs), retain distinct compositional signatures that reflect the physical conditions of their solar source regions. This study presents a statistical analysis of ICME composition dependence on solar activity during 2009--2025, covering Solar Cycle (SC) 24 and the ascen…

astro-ph.EP

Dust and Gas Transport in Substructured Nonideal MHD Wind-Launching Disks with Embedded Planets

Chun-Yen Hsu, Zhi-Yun Li, Xiao Hu, Yisheng Tu, Min-Kai Lin

Radial dust transport in protoplanetary disks is a key process shaping planet formation and disk chemistry. We investigate how this transport, along with gas transport, is regulated in wind-launching disks with embedded planets using three-dimensional nonideal MHD simulations. We find that disk substructures do not act as absolute barriers to transport. Low-mass planets leave the disk structure dominated by the magnetic wind, while a Jupiter-mass planet opens a deep gap and drives spiral shocks.…

astro-ph.IM

Achieving efficient broadband spatial filtering for LIFE: status and plan

G. Garreau, T. Birbacher, L. Desdoigts, L. D. Feinberg, A. M. Glauser, J. T. Hansen, M. Ireland, J. Pino et al.

Nulling interferometry is one of the most promising techniques that is envisioned for the imaging and characterization of exoplanets in the mid-infrared for ground-based and space-based observatories. On the ground, the upcoming Asgard/NOTT visitor instrument for the Very Large Telescope Interferometer (VLTI) is expected to be the first nuller to observe young giant exoplanets. The Large Interferometer For Exoplanets (LIFE) project aims at implementing long-baseline nulling interferometry in spa…

astro-ph.EPastro-ph.IM

Predicting Atmospheric Re-entries Using Segmented M/A Calibration of Public TLE Data

Joseph Remis

We present a reproducible method for predicting atmospheric re-entries using only publicly available Two-Line Elements (TLEs). The approach is based on a segmented calibration of the effective mass-to-area ratio (M/A), adjusted independently over intervals of at least 12 hours to suppress short-period catalogue noise. Longer segments provide a stable dynamical signal from which the effective drag behaviour can be retrieved. Applied to recent natural re-entries of rocket bodies, debris, and non-m…

astro-ph.IMphysics.ins-det

Skipper CCD readout time optimization for astronomical applications

Johannes Wüthrich, Andrin Fazan, Sean MacBride, Marcelle Soares-Santos

Skipper CCDs enable the reduction of CCD readout noise by non-destructively measuring the individual pixel charge packets multiple times. This readout noise reduction has attracted considerable interest in the astronomical community, particularly in spectroscopic surveys targeting faint objects at high redshifts. However, noise reduction via repetitive sampling leads to an unavoidable increase in readout time, often to prohibitive levels. To enable their use in astronomical applications, the opt…

astro-ph.COastro-ph.GA

Modeling the HI-Halo Connection: Evolution, Scatter, and a Halo-based Prescription for 21-cm Mock Catalogs

Mohd Kamran, Gabriella De Lucia, Marta Spinelli, Lizhi Xie, Fabio Fontanot, Michaela Hirschmann

The redshifted 21-cm line of neutral hydrogen (HI) is a powerful tracer of large-scale structure, and post-reionization HI intensity mapping is emerging as a competitive cosmological probe whose interpretation requires a description of how HI populates galaxies and dark matter halos. We characterize the HI--halo mass relation, its redshift evolution, and its intrinsic scatter, identifying its secondary dependences. We use the updated GAlaxy Evolution and Assembly (GAEA) semi-analytic model, appl…

astro-ph.GAastro-ph.SR

A universal chromosome map for globular clusters: chemical calibration and environmental regulation of the multiple populations

C. Lardo, M. Salaris, N. Bastian, C. Charbonnel, E. Dalessandro, E. Dondoglio, M. Gieles, M. G. H. Krause et al.

Chromosome maps (ChMs) are two-dimensional diagrams of UV/optical pseudocolours widely used to diagnose the multiple stellar populations (MPs) phenomenon in globular clusters. Their raw morphology is affected by the metallicity-dependent response of the photometric filters, preventing unbiased comparisons across clusters of different metallicities. We identify a cross-cluster ChM framework that accounts for this dependence, enabling an unbiased investigation of the physical drivers of MP diversi…

astro-ph.GAastro-ph.CO

Galactic Science with the LiteBIRD satellite: Spectral characterization of diffuse Galactic polarized emission at the angular power spectrum level

S. Vinzl, J. Aumont, L. Vacher, R. T. Génova-Santos, D. Adak, A. Rizzieri, H. Akamatsu, E. Allys et al.

Detection of primordial $B$-mode polarization in the cosmic microwave background (CMB) from tensor perturbations generated during inflation is a major scientific goal of future CMB missions. Its success will strongly depend on the characterization of polarized foregrounds, a challenge that the LiteBIRD satellite aims to tackle with its 15 frequency bands ranging from 40 to 402 GHz. In this work, we forecast the ability of LiteBIRD to characterize polarized dust and synchrotron emission in the di…

astro-ph.SR

Height Dependent Phase Shifts of Wave Pulses in the Lower Solar Atmosphere Measured with SUNRISE III

Andreas Lagg, H. N. Smitha, Sami K. Solanki, Tino L. Riethmüller, Achim Gandorfer, Alex Feller, Francisco A. Iglesias, Azaymi L. Siu-Tapia et al.

We report on the measurement of the height-dependent time shifts of wave pulses in the lower solar atmosphere from high-resolution spectro-polarimetric observations obtained with the SUSI instrument on board the SUNRISE III balloon-borne solar observatory during its successful science flight in July 2024. The line-of-sight velocities derived from the line-core positions of 19 spectral lines in a 2 nm-wide window around the Ca II H line were used to determine the time shifts of propagating pulses…

astro-ph.EP

A comprehensive study of comet 67P/Churyumov-Gerasimenko in the 2021/2022 apparition. II. Colorimetry, polarimetry, modeling

Vera Rosenbush, Oleksandra Ivanova, Johannes Markkanen, Igor Lukyanyk, Valerii Kleshchonok, Ludmilla Kolokolova, Colin Snodgrass, Elena Shablovinskaya et al.

This paper presents the second part of our multi-technique observational study of comet 67P during its 2021-2022 apparition. While the first paper focused on photometry and spectroscopy, here we investigate the dust color and linear polarization of the coma. Imaging in the g-sdss and r-sdss filters was obtained with the 6-m BTA SAO Telescope, and aperture polarimetry was performed with the 2.6-m Shajn Telescope (CrAO) and the 2-m RCC Telescope. Observations at phase angles of 47.9 deg (6 October…

astro-ph.GAastro-ph.SR

Anharmonic Infrared Emission of Cyano-Substituted Polycyclic Aromatic Hydrocarbon Molecules: Cyanonaphthalenes as a Case Study

Tao Chen, Kaijun Li, Aigen Li

Recent detections of cyano-substituted polycyclic aromatic hydrocarbons (cyano-PAHs) highlight them as key tracers of nitrogen heterocycles in the interstellar medium (ISM). However, their infrared (IR) identification requires anharmonic vibrational radiative models that account for dynamic cooling across diverse environments. We provide IR cascade emission spectra for neutral, cationic, and anionic 1- and 2-cyanonaphthalene (1- and 2-CNN) under representative astrophysical conditions, investiga…

astro-ph.GA

LMC-induced Perturbations in the Milky Way Halo II: Bridging Field-level Inference and Summary-level Simulation-Based Inference

Yanjun Sheng, Yuan-Sen Ting, Tomasz Różański, Xiang-Xiang Xue, Roland M. Crocker, Jiashu Pan

The gravitational interaction between the Milky Way (MW) and the Large Magellanic Cloud (LMC) drives the outer halo into dynamical disequilibrium, imprinting the masses and structural parameters of both galaxies onto the 6D phase-space distribution of halo tracers. This signal has been characterised with summary statistics ranging from low-order velocity moments to basis function expansions, yet how much information these summaries discard, and whether they are complementary, remains unclear. We…

physics.acc-phastro-ph.IM

Exploiting Non Redundant Aperture Interferometry as a Diagnostics Tool for Synchrotron Light Characterization

C. Carilli, U. Iriso, B. Nikolic, N. Thyagarajan, L. Torino

We recently introduced a novel interferometric method inspired by radio astronomy, utilizing a Non-Redundant Aperture (NRA) mask with self-calibration to fully characterize the two-dimensional transverse shape of electron beams from a single-shot interferogram. This paper reports the latest advancements in this technique, including a new data analysis approach based on closure amplitudes, which removes the need for self-calibration. We also demonstrate the method's applicability to wavefront sen…

astro-ph.GAastro-ph.SR

The UK Infrared Telescope M33 monitoring project. VI. Feedback from dusty stellar winds across the galactic disc

Atefeh Javadi, Jacco Th. van Loon, Mina Alizadeh, Seyed Azim Hashemi, Elham Saremi

We have conducted a near-infrared monitoring campaign at the UK InfraRed Telescope (UKIRT), of the Local Group spiral galaxy M33 (Triangulum). In this sixth paper of the series, we measure the dust and gas mass-loss rates by the pulsating Asymptotic Giant Branch (AGB) stars and red supergiants (RSGs) across the stellar disc of M33. We combined our time-averaged near-IR photometry with the multi-epoch mid-IR photometry obtained with the Spitzer Space Telescope, and employed a combination of spect…

astro-ph.IMgr-qcphysics.ins-det

Noise reduction in suspension control with photon-pressure actuator for CHRONOS gravitational wave detector

Daiki Tanabe, Yuki Inoue, Mario Juvenal S. Onglao

Improving sub-Hz sensitivity of gravitational wave (GW) detectors is important to detect heavier binary black hole mergers and study phenomena in stronger gravity fields. Torsion-bar-based GW detectors have been projected to focus on low-frequency GW. Among noise sources of GW detector, actuation noise induced by vibration of force sources and fluctuation of environmental magnetic fields is one that increases in low frequency. In this study, we propose photon-pressure actuator as a solution to i…

astro-ph.SR

Oscillatory reconnection and resonant response to wave excitation in 2D coronal null points

Konstantinos Karampelas, Tom Van Doorsselaere

Null points are magnetic field singularities, where the magnetic field strength rapidly drops to zero. In the solar atmosphere, null points are known sites of magnetic reconnection and wave generation and are associated with highly energetic phenomena, such as flares. The aim of this study is to explore the connection between the properties of oscillatory reconnection at null points and the latter's nature as resonant cavities for waves. We perform a set of 2D and 2.5D magnetohydrodynamics simul…

physics.acc-phastro-ph.IM

Capabilities and Limitations of Non-Redundant Aperture Interferometry for Beam Size Measurements

C. Carilli, U. Iriso, B. Nikolic, N. Thyagarajan, L. Torino, A. Turull Barot

Non-Redundant Aperture Interferometry (NRAI) is a beam characterization technique developed at ALBA in collaboration with radio-astronomy institutes. It enables the single-acquisition measurement of the full 2D transverse profile of the electron beam using visible synchrotron radiation. To better understand the technique limitations and performance, we performed extensive SRW simulations and compare them with experimental data. This paper presents the results of these studies, which define the c…

astro-ph.HE

Constraints on the VHE counterpart of two binary black hole mergers observed by the MAGIC and CTAO LST-1 telescopes

K. Abe, S. Abe, J. Abhir, A. Abhishek, V. A. Acciari, F. Acero, A. Aguasca-Cabot, I. Agudo et al.

We present very-high-energy gamma-ray observations of two binary black hole merger candidates, GW240615_113620 and GW241125_010116, performed with the Major Atmospheric Gamma Imaging Cherenkov (MAGIC) telescopes and the first Large-Sized Telescope of the Cherenkov Telescope Array Observatory's (CTAO LST-1). GW240615_113620 was the best localized event of the fourth observing run of the LIGO-Virgo-KAGRA gravitational waves interferometers. GW241125_010116 was temporally and spatially coincident w…

astro-ph.HE

Constraints on the VHE counterpart of two binary black hole mergers observed by the MAGIC and CTAO LST-1 telescopes

K. Abe, S. Abe, J. Abhir, A. Abhishek, V. A. Acciari, F. Acero, A. Aguasca-Cabot, I. Agudo et al.

We present very-high-energy gamma-ray observations of two binary black hole merger candidates, GW240615_113620 and GW241125_010116, performed with the Major Atmospheric Gamma Imaging Cherenkov (MAGIC) telescopes and the first Large-Sized Telescope of the Cherenkov Telescope Array Observatory's (CTAO LST-1). GW240615_113620 was the best localized event of the fourth observing run of the LIGO-Virgo-KAGRA gravitational waves interferometers. GW241125_010116 was temporally and spatially coincident w…

astro-ph.GA

Nebular continuum in high-redshift galaxies with JWST

Henrique Miranda, Ciro Pappalardo, José Afonso, Polychronis Papaderos, Rodrigo Carvajal

Studying the relevance of accounting for both stellar and nebular continuum emission when performing optical spectral fitting has been mainly limited to galaxies in the local Universe. The high-quality spectroscopy provided by JWST is now opening the possibility of carrying out these studies in the younger Universe. We aim to estimate the nebular continuum contribution (X$_{\text{neb}}$) of high-redshift star-forming (SF) galaxies, explore its relation to common tracers and galaxy properties, an…

astro-ph.COastro-ph.GA

Ringing of the Reionization: A first direct measurement of the intergalactic pressure smoothing scale at redshift z>4.2 as imprinted onto small-scale peculiar velocities in the Lyman-alpha forest

Vid Iršič, Matteo Viel, Martin G. Haehnelt, James S. Bolton, Ewald Puchwein, Luke I. Gilmartin

The epoch of reionization leaves detectable imprints in the thermal history of the Universe. In particular, the fast ionization fronts passing over cold gas in the cosmic web overpressurize the gas, leading to the well-established phenomenon of pressure smoothing due to the hydrodynamic response of the gas. Although the effect has been indirectly measured from the power spectra of the Lyman-$α$ forest over the past decades, very few examples exist of directly measuring the typical scale associat…

astro-ph.IM

CATKit2-HCI: a collaborative framework for advancing high-contrast coronagraph testbeds

Rémi Soummer, Iva Laginja, Emiel H. Por, Raphaël Pourcelot, Sarah Steiger, Bryony Nickson, Alexis Lau, Pierre Baudoz et al.

High-contrast exoplanet imaging requires dedicated laboratory testbeds for the development and validation of coronagraph architectures, wavefront sensing and control methods, calibration strategies, and system-level observing concepts. These testbeds often share similar software needs, yet many tools are developed independently at each institution. The CATKit2-High-Contrast-Imaging collaboration, or CATKit2-HCI, addresses this gap by providing a shared software framework for reusable HCI infrast…

astro-ph.SR

Reversive and Non-Reversive Magnetic CP Stars. I. Catalog

I. I. Romanyuk

An analysis of the distribution of signs of the longitudinal magnetic field component $B_z$ is presented for a sample of 307 chemically peculiar (CP) stars with reliably measured magnetic fields. For each star, the root-mean-square field $B_{\rm rms}$ and the extreme values of $B_z$ are used to classify the field configuration as either reversive or non-reversive. Among the 173 non-reversive stars, 100 exhibit a predominantly negative $B_z$ sign, while only 73 display a positive sign, correspond…