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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.HEphysics.plasm-phphysics.space-ph

Flares and flux ropes: an entangled story

Rony Keppens, Yang Guo, Wenzhi Ruan

Solar flares serve as standard candles for all magnetic-reconnection-based energy releases, and their consequences into the heliosphere can be modeled from first principles. This review presents the latest developments in modeling solar flares and their associated flux rope expulsions with state-of-the-art multidimensional magnetohydrodynamic (MHD) descriptions. Observationally established ingredients beyond a single-fluid, thermal plasma evolution have been incorporated to varying degrees, and…

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astro-ph.SRphysics.space-ph

Tracking a solar energetic eruption and associated energetic particles from Sun to spacecraft

D. E. Morosan, M. Baumgartner-Steinleitner, K. Bhandari, N. Dresing, G. Farwa, J. A. J. Mitchell, C. Palmroos, A. Razquin et al.

Context. Solar energetic particles (SEPs) in the heliosphere are produced by flaring processes on the Sun or shocks driven by coronal mass ejections (CMEs). Electrons, in particular, are regularly detected remotely as electromagnetic radiation (X-rays or radio emission), which they generate through various processes, as well as in situ by spacecraft monitoring the Sun and the heliosphere. Aims. We aim to combine remote-sensing and in situ observations of an energetic solar eruption to link energ…

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gr-qcastro-ph.HE

Testing Charged Black Holes Embedded in Anisotropic Matter and Surrounded by Plasma through Gravitational Lensing: Bounds from the Sloan Lens ACS Survey

Ritesh Pandey, Shubham Kala, Amare Abebe, Hemwati Nandan, G. G. L. Nashed

We investigate weak gravitational lensing by a charged black hole surrounded by anisotropic matter, described by the two-component Kiselev metric, and immersed in a homogeneous plasma. We first examine the black hole geometry and horizon structure and then derive the weak-deflection angle from the Hamiltonian description of light propagation in plasma, using an expansion with a fixed turning point that we verify against direct numerical integration. Using the gravitational lens equation, we obta…

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astro-ph.SRastro-ph.HEphysics.plasm-phphysics.space-ph

Stationary Resistive MHD Solutions Near an Isolated Three-Dimensional Magnetic Null

Kuljeet Singh Saddal, Dieter H. Nickeler, Rodrigo Meneses Pacheco, Michaela Kraus

Magnetic null points define the magnetic field topology in stellar coronae, planetary magnetospheres, and astrospheres, and are commonly associated with magnetic reconnection. We investigate the local structure of stationary three-dimensional (3D) resistive, incompressible magnetohydrodynamic (MHD) flows in the vicinity of an isolated magnetic null and an isolated velocity stagnation point, assuming that the two nulls are colocated. The governing MHD equations are solved self-consistently using…

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astro-ph.SRastro-ph.GA

Nova shells in 3D: I. A catalog of integral field spectroscopic observations

Janis B. Rodríguez-González, Edgar Santamaría, Martin A. Guerrero, Jesús A. Toalá

Classical novae eject material during thermonuclear eruptions on accreting white dwarfs, forming expanding shells whose structures and kinematics provide insights into the eruption mechanism and binary interaction. However, their intrinsic three-dimensional (3D) structures remain poorly constrained. We present the first 3D catalog of nova shells based on integral field spectroscopy, enabling us to investigate their structures beyond projection effects. We compiled observations of 19 nova shells…

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astro-ph.GA

Galactic Morpholography: Linking present-day galaxy compactness to assembly history and relic formation in the COLIBRE simulations

Maximilian Zemsch, Claudia D. P. Lagos, Chiara Spiniello, Michele Cappellari, Ángel Chandro-Gómez, Katy L. Proctor, Evgenii Chaikin, Johanna Hartke et al.

Compactness is widely used to identify candidate relic galaxies, the largely untouched survivors of the first compact massive galaxies. Yet relicness is an evolutionary rather than structural property. Using the COLIBRE cosmological hydrodynamical simulations, we test whether present-day structure traces galaxy formation and assembly histories. Six complementary tracers (stellar age, metallicity, [Mg/Fe], sSFR, velocity dispersion and ex-situ mass fraction) vary coherently across the stellar mas…

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astro-ph.GA

The physical and chemical structure of TMC-1. The spatial distribution and excitation conditions of carbon, oxygen, and sulfur bearing species: Depletion of CO and CS

J. Cernicharo, B. Tercero, N. Marcelino, G. Esplugues, G. Molpeceres, M. Agúndez

We present a detailed study of the physical and chemical structure of TMC-1 from the observed spatial distribution of HC3N, NNH+, CN, and their isotopologues, the O-bearing species C18O, C17O, CH3OH, CH3CHO, and H2CO, and the S-bearing species CS, HCS+, H2CS, and H2CCS. The well known filamentary structure of TMC-1 can be interpreted as a single cloud with a velocity gradient perpendicular to the filament, or less likely as due to the alignment of three independent clouds in the line sight with…

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gr-qcastro-ph.IM

Quantum noise and torque correlations in a torsion-bar Sagnac speed meter

Yuki Inoue, Mario Onglao, Daiki Tanabe, Masashi Hazumi, Vivek Kumar, Apimook Watcharangkool

Quantum fluctuations entering through weakly transmitting mirrors can limit a torsion-bar Sagnac speed meter for low-frequency gravitational-wave detection, even when its optical layout suppresses radiation-pressure back action. We show that, in the Cryogenic sub-Hz cROss torsion bar detector with quantum NOn-demolition Speed meter (CHRONOS), vacuum fields entering from behind the end and middle test masses can dominate the low-frequency quantum noise despite cancellation of the torques on oppos…

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astro-ph.GA

The Role of Environment in Shaping the Assembly Timelines of Massive Quiescent Galaxies at Cosmic Noon

Tianmu Gao, J. Trevor Mendel, Letizia Bugiani, Minjung Park, Sirio Belli, Joel Leja, Claudia del P. Lagos, Amir H. Khoram et al.

JWST observations of massive quiescent galaxies (MQGs) at $z\sim2$ have revealed diverse star formation histories (SFHs). In this letter, we investigate whether these variations are linked to the environment in which MQGs reside, as quantified by the host dark matter halo mass. We identify 12 MQGs from a representative sample of galaxies at $1.6<z<3.5$ obtained by the Blue Jay survey, a JWST Cycle 1 program, and infer their SFHs via modelling of the deep NIRSpec medium-resolution spectra along w…

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physics.space-phphysics.geo-ph

The Gannon Storm: Citizen science observations during the geomagnetic superstorm of 10 May 2024

Maxime Grandin, Emma Bruus, Vincent E. Ledvina, Noora Partamies, Mathieu Barthelemy, Carlos Martinis, Rowan Dayton-Oxland, Bea Gallardo-Lacourt et al.

The 10 May 2024 geomagnetic storm, referred to as the Gannon Storm in this paper, was one of the most extreme to have occurred in over 20 years. In the era of smartphones and social media, millions of people from all around the world were alerted to the possibility of exceptional auroral displays. Hence, many people not only witnessed but also photographed the aurora during this event. These citizen science observations, although not from scientific instruments operated by observatories or resea…

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astro-ph.GA

Sleeping or Dead? Probing the Quenching Mechanism of JWST Dormant Galaxies at z > 3 with ALMA

Mengyuan Xiao, Songnan Qi, Pascal A. Oesch, Longji Bing, Miroslava Dessauges-Zavadsky, Andreas L. Faisst, Mahsa Sanati, Rashmi Gottumukkala et al.

JWST has revealed a population of "dormant'' galaxies at z>3 with strong Balmer breaks and weak emission lines, whose star formation appears to have declined only recently. Whether these galaxies are undergoing a lasting transition toward quiescence or merely experiencing a temporary suppression of star formation remains unclear. We investigate their molecular gas content using archival ALMA observations of [CII]158um and CO rotational transitions. Starting from all publicly available JWST/NIRSp…

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astro-ph.IM

RPCA: a Resolved PSF reconstruction method for undersampled images

Lin Nie, Huanyuan Shan, Guoliang Li, Tobías I. Liaudat, Chengliang Wei, Peng Wei, Tianmeng Zhang, Hekun Li et al.

The Point-Spread Function (PSF) is a critical component in various astrophysical research areas, including galaxy morphology, photometric redshift determination, and weak lensing studies. As the next generation of space telescopes prepares for operations, including the China Space Station Telescope (CSST), accurate PSF modeling has become increasingly important. However, accurately modeling the PSF remains challenging, particularly for poorly sampled images. To construct reliable PSF models base…

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astro-ph.EPastro-ph.IMastro-ph.SR

On-sky performance and prospects of near-infrared CMOS detectors in exoplanet detection: first year of SPIRIT

Clàudia Janó-Muñoz, Matthew J. Hooton, Peter P. Pedersen, Didier Queloz, Khalid Barkaoui, Yasmin T. Davis, Michaël Gillon, Benjamin V. Rackham et al.

Ultracool dwarfs are promising targets for detecting and characterising temperate terrestrial exoplanets. Their flux peaks in the near-infrared, beyond the wavelength cut-off of the silicon-based CCDs used by ground-based surveys dedicated to observing them, such as SPECULOOS. We present the on-sky performance of SPIRIT (SPeculoos InfraRed Imager for Transits), an InGaAs CMOS detector on the Callisto telescope at the SPECULOOS Southern Observatory, during its first year of operation, from mid-20…

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astro-ph.GA

PDRs4All XXIII. JWST-MIRI template spectra of PAHs in the Orion Bar obtained with blind signal separation

P. Amiot, O. Berné, J. Roux-Morin, I. Schroetter, C. Boersma, A. Fuente, J. R. Goicoechea, E. Habart et al.

The aromatic infrared bands (AIBs) are observed in a wide variety of astrophysical sources, and now in unprecedented detail by the James Webb space telescope (JWST). These bands are generally attributed to the emission from polycyclic aromatic hydrocarbon (PAHs). Our aim is to extract mid-infrared AIB template spectra from JWST observations of the Orion Bar photo-dissociation region that can be used to derive PAH properties from observations of other objects. We used the JWST MIRI-MRS observatio…

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astro-ph.HEastro-ph.GA

Black Hole Binary Mergers in Galactic Nuclei: Combined Effects of Secular Dynamics and Stellar Flybys

Hao Wang, Bin Liu, Johan Samsing

Galactic nuclei, with the central supermassive black holes (SMBHs) and surrounding dense star clusters, serve as natural laboratories for studying gravitational dynamics in extreme gravitational environments. In this work, we model the long term evolution of black hole binaries (BHBs) in these environments by incorporating the tidal influence of the central SMBH, the potential of the nuclear star cluster, SMBH induced relativistic precession, and stochastic perturbations from stellar flybys. Our…

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astro-ph.HE

Linear Polarization of Synchrotron Radiation from Very-small-pitch-angle Electrons

Meng Nie, Jirong Mao

For synchrotron radiation with pitch angle $α\ll 1/γ$ where $γ$ is the electron Lorentz factor, referred to as very-small-pitch-angle synchrotron radiation, the polarization properties differ significantly from those of conventional synchrotron radiation ($α\gg 1/γ$). In this work, we investigate the linear polarization characteristics of very-small-pitch-angle synchrotron radiation from relativistic thermal and nonthermal electrons. We calculate the linear polarization by applying power-law and…

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astro-ph.EPastro-ph.IM

LiDO: The Large inclination Distant Objects Survey

Mike Alexandersen, Rosemary E. Pike, Ying-Tung Chen, Samantha M. Lawler, Mark Comte, Lowell Peltier, J. J. Kavelaars, Kathryn Volk et al.

Previous trans-Neptunian objects (TNOs) discovery surveys targeted the ecliptic plane, where the overall highest density is seen. High-inclination objects spend little time near the plane, and are thus under-represented in previous TNO surveys. The Large inclination Distant Objects (LiDO) survey targets these high-inclination populations in 34 sq$.$deg., located in two blocks 14-21 degrees north and south of the ecliptic plane, finding 148 objects, all with i>14 degrees due to survey design. A c…

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astro-ph.COastro-ph.GAastro-ph.IM

specwizard: A Public Python Framework for Creating Synthetic Absorption Spectra from Hydrodynamical Simulations

Andrés Arámburo-García, Tom Theuns, Joop Schaye, Alexey Boyarsky

We present specwizard, a publicly available modular Python package for generating synthetic absorption spectra from hydrodynamical simulations. The code combines atomic data from the National Institute of Standards and Technology database with ionisation fractions computed using the cloudy spectral synthesis code for multiple ionising backgrounds, enabling consistent modelling of bound--bound and bound--free absorption for resonant transitions of all ions. specwizard employs a column-density--co…

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astro-ph.GA

A heterogeneous set of unusual quasars selected from astrometry and broad-band photometry

C. Cheng, K. Valeckas, L. Christensen, A. Henderson de la Fuente, L. Fuglsang, V. Vuolteennaho, Pyykkinen, R. H. Rasmussen et al.

The aim of this study is to explore methods for how to identify new quasars with different properties with regard to reddening, redshift, the presence of broad absorption lines from outflows, or other rare properties affecting the broad-band colours. We use Gaia-based astrometric pre-selection to study only sources that have zero parallax and zero proper motion within errors. We subsequently match these sources with information from wide-area photometric surveys and build colour-colour diagrams.…

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astro-ph.GA

Strong gravitational lensing with Euclid

Alessandro Sonnenfeld

Euclid data is going to lead to the discovery of approximately 10^5 new strong gravitational lenses, thereby increasing the number of known lenses by a factor of 30. Such an impressive jump has the potential to revolutionise the field of strong lensing, by covering an ever-increasing range in the parameter space occupied by the lenses and lensed sources, and by uncovering rare and precious strong lens systems. The first quick data release of Euclid has already revealed hundreds of lenses, giving…

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astro-ph.GA

Large dust grains escaping from a supernova remnant

Evgenii O. Vasiliev

Dust grains produced in the supernova (SN) ejecta at early ages are partially destroyed in hot gas of the SN remnant. Large grains owing to their inertia can overtake the forward shock front of the remnant and move through the ambient interstellar medium. Using one-dimensional gas dynamics including the dust destruction we study the transport of dust grains inside the SN remnant and the ambient medium. Here we estimate the surviving and escaping mass fractions depending on the cut-off (maximum)…

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astro-ph.IMastro-ph.GA

Identifying Planetary Nebulae Candidates from IPHAS and VPHAS+ Surveys via YOLO Deep Learning Models

Titouan Sérandour, Anne-Laure Méalier, Bruno Colicchio, Dominique Daniel, Philippe Gilberton, Philippe Oros, Thomas Boch, Djaffar Ould Abdeslam et al.

We present a deep learning detection method capable of effectively identifying planetary nebulae (PNe) on IPHAS and VPHAS+ surveys. Our detection pipeline is based on the YOLO architecture and is adaptable to other datasets. Using the HiPS system, we preprocess and augment the $r$, $i$, and $Hα$ bands to produce two red, green, and blue (RGB) image datasets: (1) $640 \times 640$ px images at full resolution, and (2) $1 280 \times 1 280$ px images designed to capture extended objects up to $0.2$…

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astro-ph.SR

High-Frequency Transverse Waves in Chromospheric Fibrils Revealed by DKIST

Qifan Dong, Xiaoli Yan, Zhike Xue, Liheng Yang, Jincheng Wang, Yadan Duan, Zhe Xu

Chromospheric fibrils are ubiquitous dynamical structures that can support magnetohydrodynamic waves and may contribute to energy transport in the solar atmosphere. Using high-resolution observations from the Visible Broadband Imager (VBI) onboard the Daniel K. Inouye Solar Telescope (DKIST), we investigate transverse oscillations of H$α$ fibrils. Our observations encompass both quiet-Sun and active regions. The results reveal that high-frequency transverse oscillations are highly prevalent in f…

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astro-ph.SR

Evidence for Suppressed Non-thermal Broadening in a Flare Ribbon from Stereoscopic Observations

Ziwen Huang, L. P. Chitta, L. Teriaca

Flare ribbons mark the footpoints of newly reconnected magnetic loops and are commonly associated with strong plasma flows and enhanced non-thermal broadening of transition-region lines due to impulsive energy deposition. However, the mechanisms governing energy transport into flare ribbons remain uncertain, particularly under different magnetic field configurations. We investigate the energy deposition process at a flare ribbon near a sunspot by determining the physical nature of its small-scal…

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astro-ph.GAastro-ph.IM

Microcaustics: Fast GPU-Accelerated Dynamical Microlensing of Time-Dependent Extended Sources

Joshua Fagin, Connor Stone, James Hung-Hsu Chan, Sophia Miskiewicz, Henry Best, Paras Sharma, Matthew O'Dowd, Laurence Perreault-Levasseur et al.

Gravitational microlensing probes unresolved quasar accretion disc structure and compact objects in lens galaxies and is an important systematic in strong-lens time-delay cosmography. Most analyses use static microlensing map simulations because evolving individual microlenses and caustics is computationally prohibitive. We present Microcaustics, a GPU-accelerated Python package built on PyTorch for dynamical microlensing of time-dependent extended sources in strong gravitational lenses. It comb…

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astro-ph.HEastro-ph.SRhep-ph

Constraint on particle mass of dark matter based on XTE J1814-338 observation and DANS model

Lin Wang, Dehua Wen

The small observed radius of neutron star XTE J1814-338 (with mass of $1.21_{-0.05}^{+0.05}$ $M_{\odot}$ and radius of $7_{-0.4}^{+0.4}$ $\rm{km}$) poses a great challenge to the traditional neutron star model composed of normal nuclear matter. The dark matter admixed neutron star (DANS) model provides a clue to solve this challenge. By employing the self-interacting fermionic dark matter model, we investigate the effects of dark matter parameters including the particle mass, self-interaction st…

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astro-ph.SR

Post-merger rotational evolution of magnetised single hot subdwarfs results in slow rotation due to magnetic braking

Facundo D. Moyano, Zhengwei Liu, Zhanwen Han, Xuefei Chen, Tiara Battich, Philipp Podsiadlowski

Single hot subdwarfs are believed to form through mergers of helium-core white dwarfs, which can lead to large-scale magnetic fields generated during the merger, and may be observable at the surface once they evolve into the stable core-helium burning phase. As a post-merger product, the orbital angular momentum of the binary system that forms it, could lead to a rapidly rotating hot subdwarf. But previous models were not able to explain the rather slow rotational velocities of observed single h…

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astro-ph.HEhep-ph

Correlation of galactic very-high-energy gamma-ray sources detected by LHAASO with high-energy neutrinos

Long-Yu Zhang, Kai Wang

We conducted an investigation into the possible correlation between very-high-energy (VHE, $E>$ 0.1 TeV) gamma-ray sources, as identified by the Large High Altitude Air Shower Observatory (LHAASO), and high-energy neutrino events captured by the IceCube Neutrino Observatory. For this analysis, we utilized the First LHAASO catalog, which comprises 90 VHE gamma-ray sources, and the IceCube Event Catalog of Alert Tracks (IceCat-1), which includes 348 track-like neutrino events. Through Monte Carlo…

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astro-ph.IM

Development and characterization of a millimeter-wave circular polarization observation method using a quarter-wave plate with Simons Array

Kana Sakaguri, Darcy R. Barron, Yuji Chinone, Matthew Ryan Chu, Nicole Farias, Takuro Fujino, Masaya Hasegawa, Masashi Hazumi et al.

We have developed and demonstrated a method for measuring circular polarization at 90 GHz by combining a quarter-wave plate (QWP) and a continuously rotating half-wave plate (HWP). While many bolometric experiments at millimeter wavelengths focus on measuring linear polarization, observations of circular polarization in millimeter waves may open a new window into astrophysics and cosmology. We present a novel approach to circular-polarization search using linear-polarization-sensitive detectors…

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astro-ph.HE

A possible evolutionary connection between high-mass X-ray binary pulsars and isolated rotation-powered pulsars

Jun Yang

We investigate the long-term spin evolution of high-mass X-ray binary (HMXB) pulsars in the Small Magellanic Cloud (SMC) using archival measurements of spin periods and period derivatives from XMM-Newton, Chandra, and RXTE. In the P-|dP/dt| plane, the HMXB pulsars follow an approximately linear relation in log-log space with a slope of 1.02 +/- 0.11, similar to the trend shown by the youngest isolated rotation-powered pulsars (RPPs; e.g., Manchester et al., 2005; Lorimer and Kramer, 2005). For c…

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