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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.HE

Outflow Behavior from the Transonic Advective Disks: A Hydrodynamical Simulation Study

Sanjit Debnath, Indranil Chattopadhyay, Raj Kishor Joshi, Philippe Laurent, Priyesh Kumar Tripathi, M. Saleem Khan

We investigate the properties of outflows from the transonic advective accretion disk using hydrodynamical numerical simulations. We consider two different disk temperatures with an order-of-magnitude difference. For the hotter disk, we adopt initial conditions for velocity, specific angular momentum, and temperature from analytical solutions. In the colder disk case, the velocity and angular momentum profiles are kept identical, while an order of magnitude reduction in the temperature. The simu…

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hep-phastro-ph.COastro-ph.HEastro-ph.IM

Revising Indirect Dark Matter Constraints with Updated Astrophysical $J$-Factor Priors

Giacomo D'Amico

Indirect searches for particle dark matter with gamma-ray experiments have produced a large number of constraints on the annihilation cross section (or decay lifetime) over a wide range of dark matter masses. These constraints depend critically on the assumed astrophysical $J$ factor and its uncertainty, which encodes the dark matter distribution in the target and represents the dominant source of systematic uncertainty. As improved observational data and dynamical modeling are expected to revis…

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astro-ph.SRastro-ph.IM

eROSITA all-sky survey - stars and optical loading

J. Robrade, K. Dennerl, M. J. Freyberg, J. H. M. M. Schmitt

eROSITA (extended ROentgen Survey with an Imaging Telescope Array) on board the Spectrum-Roentgen-Gamma (SRG) spacecraft has performed the eROSITA All-Sky Survey (eRASS) at X-ray energies. We study the brighter stars to assess the impact of optical loading in the eROSITA all-sky survey, here specifically the eRASS:3. Further we use thermal plasma models to investigate the general properties of stellar eRASS sources and compare optical loading affected stars to coronal sources. We compare data fr…

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astro-ph.HEastro-ph.GAhep-ph

Paleodetectors for neutrino signals from diverse Galactic stellar collapses

Mahiro Yamasaki, Ken'ichiro Nakazato

The detectability of neutrinos from past Galactic core collapse supernovae (SNe) is investigated in terms of nuclear recoil tracks in ancient minerals, known as paleodetectors. To account for the diversity of core-collapse outcomes, variations in neutron star (NS) masses as well as failed SNe leading to black hole (BH) formation are taken into account. The role of the nuclear equation of state (EOS) is also considered, as it determines NS radii and maximum masses. The enhancement of sensitivity…

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astro-ph.IMastro-ph.CO

Optimizing the extraction of information from redshift probability distribution functions

Rodrigo Duarte, Valerio Marra

Photometric redshifts are essential for large-scale structure analyses, yet extracting optimal point estimates and reliability measures from the probability distribution functions (PDZs) delivered by photo-$z$ pipelines remains an open challenge. We introduce turboPDZ, a machine-learning framework that optimizes both quantities directly from the PDZ. We apply the framework to PDZs from the three independent HSC-SSP PDR3 pipelines (DEmP, DNNz, Mizuki) across Wide and DUD layers. Each PDZ is compr…

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astro-ph.SRastro-ph.EPastro-ph.GAphysics.space-ph

An interstellar energetic and non-aqueous pathway to peptide formation

Alfred Thomas Hopkinson, Ann Mary Wilson, Joe Pitfield, Alejandra Traspas Muiña, Richárd Rácz, Duncan V. Mifsud, Péter Herczku, Gergő Lakatos et al.

The origin of the molecular building blocks of life is a central question in science. A few $α$-amino acids such as glycine, the simplest proteinogenic amino acid, have been detected in meteorites and comets, indicating an extraterrestrial origin for some prebiotic molecules. However, the formation of peptides, short chains of $α$-amino acids linked by peptide bonds, under astrophysical conditions has remained unresolved. Here we show that the building blocks of proteins can form in interstellar…

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astro-ph.EPastro-ph.SR

Exploring the radial velocity variations of RY Lup with VLT/ESPRESSO: Binary versus spot hypotheses

Hala Alqubelat, Claudia Di Maio, Antonio Frasca, Carlo F. Manara, Monika G. Petr-Gotzens, Enrico Ragusa, Evelyne Alecian, Louise D. Nielsen et al.

Stellar multiplicity is a possible cause for creating protoplanetary disc substructures, as tidal forces from a close-in spectroscopic companion can carve out gaps and shape disc architecture. However, in young, active systems, the radial velocity (RV) signatures are often complicated by stellar activity. We investigate RY Lup, a classical T Tauri star hosting a disc with a ~60 au cavity, where studies with Gaia astrometry and VLT/SPHERE imaging hinted at an unseen companion. Using high-resoluti…

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astro-ph.HE

Effect of Multi-Species Plasma on Fanaroff-Riley Radio Jets

Priyesh K. Tripathi, Indranil Chattopadhyay, Raj Kishor Jpshi, Ritaban Chatterjee, Sanjit Debnath, M. Saleem Khan

The Fanaroff-Riley (FR) dichotomy observed in extragalactic radio jets has been attributed to a range of possible mechanisms, including intrinsic jet properties such as the presence of different species in the plasma. Jet material may span from a pure electron-positron pair plasma to mixed plasmas containing electrons, positrons, and protons, or even to hadronic jets made up of electrons and protons only. To investigate this aspect, we present results from three-dimensional simulations of low-po…

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astro-ph.HE

Effect of Multi-Species Plasma on Fanaroff-Riley Radio Jets

Priyesh Kumar Tripathi, Indranil Chattopadhyay, Raj Kishor Joshi, Ritaban Chatterjee, Sanjit Debnath, M. Saleem Khan

The Fanaroff-Riley (FR) dichotomy observed in extragalactic radio jets has been attributed to a range of possible mechanisms, including intrinsic jet properties such as the presence of different species in the plasma. Jet material may span from a pure electron-positron pair plasma to mixed plasmas containing electrons, positrons, and protons, or even to hadronic jets made up of electrons and protons only. To investigate this aspect, we present results from three-dimensional simulations of low-po…

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astro-ph.SR

Energetic Particle Acceleration and Transport: Interplanetary Coronal Mass Ejections and Shocks

Olga E. Malandraki, Christina M. S. Cohen, Joe Giacalone, Leng Ying Khoo, Domenico Trotta, Laura Rodriguez-Garcia, Athanasios Kouloumvakos, Zheyi Ding et al.

Solar Energetic Particles from suprathermal (few keV) up to relativistic (few GeV) energies constitute an important contributor to the characterization of the space environment. Emitted from the Sun they are associated with solar flares and shock waves driven by Coronal Mass Ejections. This review presents important recent results of the study of Interplanetary CMEs and shocks in relation to energetic particle acceleration and transport, taking advantage of multi-point, multi-instrument observat…

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astro-ph.GAastro-ph.IMgr-qc

Effects of a disk structure on stellar motion at the Galactic Center

Arianna Foschi, Frederic H. Vincent, Thibaut Paumard, Guy Perrin

Stellar orbits are key for probing the environment of the supermassive black hole at the Galactic Center, Sagittarius A$^*$. So far, the mass around SgrA$^*$ has been assumed to be spherically distributed. However, the extended mass may instead be flattened, creating disk-like structures. We investigate the effects that a thin disk structure would have on stars at the Galactic Center, focusing on star S2 and S301 and the clockwise stellar disk. We derive analytically the acceleration exerted by…

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astro-ph.SRastro-ph.EPphysics.space-ph

The Internal Magnetic Field Structure of ICMEs in the Heliosphere

Ziwei Huang, Zhenjun Zhou, Yudong Ye, Ming Xiong, Yuming Wang, Yutian Chi, Daniel Heyner, Hans-Ulrich Auster et al.

Interplanetary coronal mass ejections (ICMEs) are major drivers of heliospheric disturbances and space-weather effects. Here we present a multi-spacecraft study of 96 magnetic clouds (MCs) distributed over a broad range of heliocentric distances, and reconstruct their internal magnetic structure with a uniform-twist Gold--Hoyle (GH) flux-rope model. From the fits, we derive the axial field strength $B_0$, the twist density (turn density) $τ$, the GH parameter $ω$, and the integrated twist number…

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gr-qcastro-ph.HEastro-ph.IMstat.AP

Bayesian nonparametric estimation of correlated gravitational wave detector network noise using matrix-gamma process priors

Yixuan Liu, Renate Meyer, Nelson Christensen, Jeung Eun Lee, Jianan Liu, Patricio Maturana-Russel, Avi Vajpeyi

This paper addresses the important problem of estimating the noise spectral density of next-generation gravitational-wave detectors, such as LISA and the Einstein Telescope (ET), where cross-channel correlations must be accounted for to avoid biased parameter estimation of gravitational-wave signals. Unlike approaches that estimate test-mass and optical-metrology-system noise separately at the single-link level and then map them to the Time-Delay Interferometry (TDI) channels through known trans…

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astro-ph.GAastro-ph.CO

An Enhanced Catalog of Gaia DR3 Galaxy Candidates with Spectroscopic and Machine-Learning Photometric Redshifts

Junghyun Hwang, Ho Seong Hwang

We present an updated galaxy catalog based on the Gaia Data Release 3 (DR3) Galaxy Candidates table, augmented with both spectroscopic and machine-learning based photometric redshift estimates. While the original catalog of Gaia DR3 galaxy candidates provides an unprecedented all-sky sample of extragalactic sources, its scientific utility for extragalactic and cosmological studies has been limited by the absence of redshift information and by its relatively low source purity. To address these li…

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astro-ph.IM

Impact of microlens shape on the performance of Laser Guide Star wavefront sensors for ELT-class telescopes

Paul Rouquette, Benoit Neichel, Cédric Taisir Heritierc, Pierre Jouve, Anne Costille, Kjetil Dohlen, Thierry Fusco

Laser Guide Star (LGS) adaptive optics systems on extremely large telescopes (ELTs) rely on Shack-Hartmann wavefront sensors (SHWFS) equipped with large-format microlens arrays. Manufacturing imperfections in the microlens surface profile degrade spot quality and reduce centroiding accuracy, yet this effect is rarely quantified in the context of full AO system performance. This paper presents a comprehensive characterization of the impact of microlens shape on LGS wavefront sensing, using the MO…

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astro-ph.IM

Towards an Extended VLTI: Turbulence Characterization for Kilometer-Scale Optical Links at Paranal

B. Neichel, T. Pichon, G. Bourdarot, D. Perez, E. Vera, V. Chambouleyron, T. Fuscod, C. -T. Heritier et al.

Future extensions of the VLTI aim to push infrared interferometry toward kilometer scale baselines, enabling angular resolutions of a few tens of micro-arcseconds. A first step would couple a new telescope on the VISTA platform to the existing VLTI infrastructure, creating a 1.4 km baseline at Paranal. Among the possible beam-transport solutions, direct free-space transmission with adaptive-optics (AO) pre-compensation, inspired by Free-Space Optical (FSO) communications, offers an attractive co…

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astro-ph.IMastro-ph.COastro-ph.EPastro-ph.GAastro-ph.SR

HARMONI@ELT: instrument design, performance, and science capabilities

B. Neichel, J. Dunlop, S. Chittick, D. Le Mignant, M. Swinbank, A. de Lorenzo-Caceres, W. Taylor, M. Tecza et al.

HARMONI is the integral field spectrograph for the Extremely Large Telescope (ELT). Designed as the primary workhorse near-infrared spectrograph of the ELT, it will deliver spatially resolved spectroscopy at diffraction-limited angular resolution over the wavelength range 0.75 - 2.4 um, addressing science questions ranging from the characterization of exoplanet atmospheres to the internal kinematics of galaxies at the epoch of reionization. This paper presents the current status of the HARMONI p…

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astro-ph.SRastro-ph.IM

Probing the Physics of the Solar Corona with High-Resolution Observations using SKA-Mid

Mark C. M. Cheung, John S. Morgan, Rohit Sharma, Sven Wedemeyer, Gregory Fleishman, Matthias Rempel

We examine the capability of the SKA-Mid telescope for probing solar coronal structure and evolution. Using radiative magnetohydrodynamics simulations of a solar flare, we synthesise radio emission in bands available to SKA-Mid. SKA-Mid observations would provide important constraints on plasma processes that are important to diverse astrophysical environments, including flares/eruptions, magnetic reconnection, particle acceleration, and gyro-emission processes. Observations with the AA4 configu…

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physics.opticsastro-ph.IMphysics.ins-det

Addressing rotational motion on gravitational waves detectors

Chiara Di Fronzo, Jian Liu

The rotational components of Earth's seismic motion are one of the major contributions to limit the sensitivity of terrestrial gravitational-wave detectors at frequencies below 10 Hz. The fundamental challenges lie in understanding the angular degrees of freedom of seismic motion and how they can be accurately measured. These are both crucial steps for developing an adequate control system to suppress seismic motion and maintaining resonance in the detector cavities. This review shows why the ro…

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astro-ph.SR

Observations of a Solar Jet Triggered by Reconnection between Super-penumbral Fibrils and a Mini-filament

Liheng Yang, Xiaoli Yan, Qingmin Zhang, Zhike Xue, Zhe Xu, Jincheng Wang, Fangyu Xu, Yian Zhou et al.

Coronal jets are highly dynamic phenomena in the solar atmosphere, yet their driving mechanisms remain an active topic of investigation. In this paper, we report a coronal jet triggered by the interaction between super-penumbral fibrils and a mini-filament, based on coordinated observations from the New Vacuum Solar Telescope (NVST), the Chinese H$α$ Solar Explorer (CHASE), and the Solar Dynamics Observatory (SDO). The fibrils were anchored between the negative-polarity region of a sunspot and a…

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gr-qcastro-ph.HE

Dendro-GR at high mass ratios with high spins

William K. Black, David W. Neilsen, Eric W. Hirschmann, David F. Van Komen

The Laser Interferometer Space Antenna (LISA) launches in less than a decade; it will detect spinning high-mass-ratio binary black hole inspirals annually, alongside other third-generation gravitational wave detectors. High-mass-ratio systems occupy a regime where numerical-relativity simulations remain computationally expensive and technically demanding, especially with high spins at precessing orientations. This portion of parameter space thus remains undersampled, leading to significant bias…

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astro-ph.SR

Three-dimensional Magnetic Field Structure of a Quiet-Sun Region Revealed by Sunrise III/SCIP

Masahito Kubo, Yukio Katsukawa, Yusuke Kawabata, Takayoshi Oba, Hirohisa Hara, Toshifumi Shimizu, Ryohtaroh T. Ishikawa, Takuma Matsumoto et al.

The balloon-borne stratospheric solar observatory Sunrise III successfully completed 6.5 days of observations in July 2024. One of its focal-plane instruments, the Sunrise Chromospheric Infrared spectroPolarimeter (SCIP), is a slit-scanning spectropolarimeter that simultaneously measures full Stokes profiles of multiple spectral lines in the 850 nm and 770 nm bands. SCIP obtained an unprecedented data set of a quiet-sun region near disk center, covering a $58'' \times 58''$ field of view. With a…

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astro-ph.SR

Three-dimensional Magnetic Field Structure of a Quiet-Sun Region Revealed by Sunrise III/SCIP

Masahito Kubo, Yukio Katsukawa, Yusuke Kawabata, Takayoshi Oba, Hirohisa Hara, Toshifumi Shimizu, Ryohtaroh T. Ishikawa, Takuma Matsumoto et al.

The balloon-borne stratospheric solar observatory Sunrise III successfully completed 6.5 days of observations in July 2024. One of its focal-plane instruments, the Sunrise Chromospheric Infrared spectroPolarimeter (SCIP), is a slit-scanning spectropolarimeter that simultaneously measures full Stokes profiles of multiple spectral lines in the 850 nm and 770 nm bands. SCIP obtained an unprecedented data set of a quiet-sun region near disk center, covering a $58'' \times 58''$ field of view. With a…

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astro-ph.GAastro-ph.SR

Stellar Population Astrophysics (SPA) with the TNG. Beyond the iron peak: Galactic evolution of molybdenum, ruthenium and zirconium through open clusters

Natalia Alvarez-Baena, Valentina D'Orazi, Christopher Sneden, Athanasios Psaltis, Frédéric Thévenin, Angela Bragaglia, Tamara Mishenina, Shilpa Bijavara Seshashayana et al.

Context: Open clusters serve as key laboratories for studying the chemical evolution of the Milky Way. In particular, leveraging these coeval groups of stars to study elements beyond the iron peak provides insights into heavy-element nucleosynthesis, whose origins remain uncertain. Aims: This work aims to determine the Mo, Ru, and Zr abundances for 81 stars across 30 open clusters. We compare these new chemical patterns with those of key reference elements (Y, Sr, Eu), which were previously deri…

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astro-ph.EP

Dynamical evolution and surface accretion of DART impact ejecta in the (65803) Didymos system

Xiaoyu Fu, Nicolo Stronati, Stefania Soldini, Fabio Ferrari, Carmine Giordano, Paolo Panicucci, Alessandro Rossi, Adriano Campo Bagatin et al.

The DART spacecraft impacted Dimorphos, the small moonlet of Didymos binary system, on 26 September 2022. The impact ejected dust, fragments, and boulders into the near-binary environment. In November 2026, ESA's Hera mission is expected to arrive at the binary system to characterise both asteroids and investigate the post-impact consequences in detail. In this research, we aim to investigate the dynamical evolution of DART-generated impact ejecta and to quantify their surface accretion patterns…

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astro-ph.SRastro-ph.GA

Ultracool and Brown Dwarf Candidates Identified via CatWISE-2MASS-Gaia DR3

Daniel Majaess, Dante Minniti, Matias Gomez, Roberto K. Saito, Maria G. Navarro

Ultracool and brown dwarf candidates ($d_{\odot}\lesssim 125$ pc, $|b|>8^{\circ}$) were identified via multiband and astrometric data from CatWISE ($W_1W_2$), 2MASS ($JHK_s$), and Gaia DR3 ($G$, $G_{RP}$, $π$, $μ_α$, $μ_δ$). $N\approx 11.8 \times 10^3$ candidates emerged once simultaneously constrained by color and absolute magnitude criteria (e.g., $G-W_2 \ge 1.75(G-J)-2.25$), whereby $\simeq 350$ sources are absent from the Gaia Ultracool Dwarf (UCD) catalog. Spectral types were approximated u…

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astro-ph.GA

Automated Computer Vision Cluster Identification in the Fireworks Galaxy

Debby Tran, Benjamin F. Williams, Emily M. Levesque, Tobin M. Wainer, Emerson Bowles, Bo-Eun Choi, L. Clifton Johnson, Anil C. Seth et al.

We present the integrated photometry, radii, and spatial distribution of young ($\leq$ 25 Myr) star cluster candidates in NGC 6946. NGC 6946, also known as the Fireworks Galaxy, is a highly star-forming galaxy with numerous young massive clusters. We have developed a modified computer vision algorithm using photometry from images taken with Hubble Space Telescope (HST) Wide Field Camera 3 Ultraviolet channel (WFC3/UVIS) F275W and F336W filters to identify and outline candidate clusters. We descr…

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astro-ph.GA

The evolution of galaxy dust scaling relations in the COLIBRE simulations

Aswin P. Vijayan, James W. Trayford, Joop Schaye, Sylvia Ploeckinger, Andrea Gebek, Nick Andreadis, Maarten Baes, Alejandro Benítez-Llambay et al.

We present dust scaling relations across cosmic time ($0 \le z \le 15$) for galaxies in the COLIBRE cosmological simulations. COLIBRE self-consistently tracks dust production, growth, destruction, and grain size evolution within a multiphase interstellar medium. Using volumes up to $(400\, {\rm cMpc})^3$ at three mass resolutions ($10^{5}-10^7$ M$_{\odot}$), we predict the dust mass function, cosmic dust mass density, and key dust scaling relations (dust-to-gas ratio, dust-to-metal ratio, grain…

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astro-ph.HEastro-ph.IM

QuickGWecc: Fast Bayesian pipeline for searching eccentric binaries in pulsar timing array data

Lankeswar Dey, Bence Bécsy, Abhimanyu Susobhanan, Maria Charisi

Recent pulsar timing array (PTA) results have provided evidence for the presence of a nanohertz gravitational wave (GW) background, most likely originating from a population of supermassive black hole binaries (SMBHBs). The next major milestone is the detection of continuous GWs (CGWs) from an individual SMBHB and the identification of its electromagnetic counterpart. Typically, searches for CGWs in PTA data assume binaries in circular orbits. However, theoretical studies indicate that binaries…

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astro-ph.SR

Long-Slit Spectroscopy Of Herbig-Haro Outflow System, Associated With IRAS 01166+6635

T. A. Movsessian, T. Yu. Magakian, A. V. Moiseev

We present long-slit spectroscopic observations of the outflow associated with an infrared source IRAS 01166+6635, conducted with the 6-m telescope of the Special Astrophysical Observatory using the SCORPIO-2 focal reducer. The structure of the flow as investigated in detail, its position-velocity diagrams are constructed. The electron densities of the several knots in the outflow were estimated, revealing a decrease in its density with increasing distance from the driving source.

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