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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.GAastro-ph.SR

Origins of complex organic molecules in L1551 IRS 5: Interplay of thermal heating and accretion shocks

Ji-hyun Kang, Jeong-Eun Lee, Seokho Lee, Shigehisa Takakuwa

Complex organic molecules (COMs) are typically observed in the warm inner envelopes of Class 0 protostars. In more evolved Class I sources, COM emission is confined to the compact inner disk and obscured by high dust opacity, but the FU Orionis-type binary L1551 IRS 5 offers a valuable opportunity to probe disk chemistry, as its outburst luminosity thermally sublimates ices out to large radii. We sought to spatially resolve the origins of COMs in this system to distinguish between central radiat…

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astro-ph.SRastro-ph.HE

SN 2024afyu interpreted as a Pair Instability Supernova

P. J. Pessi, S. Barmentloo, Ł. Wyrzykowski, S. Schulze, J. Sollerman, A. Gangopadhyay, P. J. Mikołajczyk, S. Rose et al.

Pair-instability supernovae (PISNe) are the predicted explosions of very massive stars triggered by electron-positron pair production. Numerous transients have been proposed as PISN candidates, yet none has provided unambiguous confirmation of this explosion mechanism. The predicted strengths of nebular emission lines offer a powerful means of testing the PISN scenario. We investigate the nature of SN 2024afyu, a nearby (z = 0.0085), long-lived (trise = 85 +- 11.7 days) SN with peculiar spectral…

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gr-qcastro-ph.HEastro-ph.SR

Nonradial oscillations of realistic anisotropic neutron stars: Polar modes

L. M. Becerra, José F. Rodríguez-Ruiz, E. A. Becerra-Vergara, F. D. Lora-Clavijo

In this work, we study the polar perturbations of static, spherically symmetric neutron stars with anisotropic pressure in full general relativity, including linear-order perturbations of both the metric and the fluid. We calculate the $f$-mode frequencies and the corresponding damping times using a consistent treatment of the perturbation of the radial vector $k^α$. In particular, its Lagrangian perturbation $Δk^α$ is determined by the metric perturbations and the fluid Lagrangian displacement…

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astro-ph.SRastro-ph.GA

Precise physical and kinematical parameters of massive eclipsing binaries in the Small Magellanic Cloud

M. Kaya, Ö. Çakırlı, B. Hoyman, O. Özdarcan, T. Yontan, R. Canbay

The formation of massive stars serves an important field of study, requiring research into whether these stars need to form together within clusters of low-mass stars or if they are able to form independently. Currently, there has been an increase in the number of massive stars found far from clusters in the Milky Way (MW) and Small Magellanic Cloud (SMC). The existence of isolation and composition in binary systems is an uncommon phenomenon among massive stars, and their rare occurrence present…

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astro-ph.GA

The Role of Dark Matter in Driving Disk Perturbations: Application to LMC-SMC Like Galaxy Interactions

Himansh Rathore, Hayden R. Foote, Gurtina Besla, Silvio Varela-Lavin, Nicolas Garavito-Camargo, Martin D. Weinberg, Facundo A. Gomez, Kathryne J. Daniel et al.

Dark-matter (DM) models predict that satellite galaxies distort their host's DM halo. As such, both the satellite and the distorted halo can perturb the host's stellar disk. The LMC-SMC system is a nearby $\sim1:10$~mass-ratio binary with a well-constrained orbit and well-characterized LMC disk perturbations. Hence, the system offers unique opportunities to test DM theory, provided the impact of halo torques on the LMC's disk can be characterized along with the SMC's torques. We use halo Basis F…

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astro-ph.GAastro-ph.HE

A pilot submillimeter search for IceCube neutrino counterparts: JCMT follow-up and dusty-galaxy catalog associations

Yuji Urata, Kuiyun Huang

The submillimeter band offers a complementary route to identifying electromagnetic counterparts of high-energy neutrinos, tracing relativistic transients and persistent dust-obscured galaxies. We present a pilot search combining JCMT/SCUBA-2 follow-up of IceCube events with catalog searches for bright high-redshift dusty systems. Among nine rapidly observed IceCube fields, sources of particular interest were found in three: JCMT0402-0424 ("Shadow Blaster") in IC 210922A, a transient-like source…

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astro-ph.SR

An Approximate Bayesian Deep Learning Approach for Uncertainty-aware Differential Emission Measure Estimates in the Solar Corona from the SDO

N. Balodhi, R. J. Morton

Accurately estimating the temperature distribution of solar coronal plasma, known as the Differential Emission Measure (DEM), is vital for understanding the thermodynamics of the corona and associated heating. However, recovering the DEM from multispectral observations like those from the Atmospheric Imaging Assembly (AIA) on board NASA's Solar Dynamics Observatory (SDO) is a mathematically ill-posed, underdetermined problem, and traditional regularization-based inversion methods are computation…

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astro-ph.GA

LEGGOS: Direct abundances of N, O, Ne, S, and Ar in five lensed galaxies at Cosmic Noon

Brian Welch, Gourav Khullar, Taylor A. Hutchison, Keren Sharon, Pedram Abedi, Matthew B. Bayliss, Michael Florian, Dylan Berry et al.

We present direct $T_e$ chemical abundances in five strongly lensed galaxies at Cosmic Noon ($2.481 \leq z \leq 3.625$) using JWST/NIRSpec data from the LEGGOS survey. We measure gas-phase abundances of N, O, S, and Ar in all five galaxies, and Ne in two galaxies. Three galaxies have electron temperature constraints from multiple different ionization zones, and we find that these are broadly consistent with temperature scaling relations observed in both local and high-$z$ galaxies. We find a ran…

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astro-ph.GA

LEGGOS: A Shocking Lack of Evidence for Shocks at sub-kiloparsec Scales at 2 < z < 4

Nikko J. Cleri, Taylor A. Hutchison, Brian Welch, Gourav Khullar, Matthew B. Bayliss, Håkon Dahle, Michael Florian, Michael D. Gladders et al.

Here we present the first systematic search for shocks in six gravitationally lensed galaxies at 2.37 < z < 3.625 with JWST/NIRSpec integral field spectroscopy from the LEnsing and Galaxy Growth: Observing Substructures (LEGGOS) survey. We employ diagnostics that utilize the fluxes and kinematics of shock-sensitive rest-frame optical emission lines H\b{eta}, [O iii] λ5008, [O i] λ6302, Hα, [N ii] λ6585, and [S ii] λλ6718, 6733. We find that, on pixel, clump, and galaxy-integrated scales, the LEG…

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nucl-thastro-ph.HEhep-ph

An EOS-Driven Extension of NSCool for Compact Star Cooling with Hadronic and Quark Degrees of Freedom

Federico Nola, Fernando Arias-Aragón

We present an EOS-driven extension of the NSCool thermal evolution code that enables complete tabulated equations of state to be treated within a single composition-based input structure. The generalized NEW interface includes additional baryonic fractions, a bosonic composition variable, the hadronic volume fraction, and quark fractions, allowing nucleonic, hyperonic, resonant-baryonic and hybrid hadron-quark configurations to be handled within the same workflow. The neutrino sector is extended…

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astro-ph.SR

Global 3D simulations of convection and dynamos in Red Giants

Carolina Ortiz-Rodríguez, Petri Käpylä, Juan Pablo Hidalgo, Dominik Schleicher, Robi Banerjee

Understanding the internal dynamics of red giants is essential for studying angular momentum transport and magnetic field generation during stellar evolution. We present three-dimensional magnetohydrodynamic simulations of a $1M_{\odot}$ red giant at the bottom of the red giant branch using a star-in-a-box setup with the Pencil Code, together with ongoing efforts to refine the numerical model. By varying the rotation rate, we explore different Rossby numbers and identify systematic changes in th…

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astro-ph.HE

Abundance Stratification in Type Ia Supernovae -- VIII. The 03fg-like SN\,2012dn: a double-degenerate merger interpretation

Charles J. Aouad, Paolo A. Mazzali, Stephan Hachinger, Chris Ashall

A detailed study using abundance tomography of SN 2012dn, a peculiar Type Ia supernova, is presented. Despite exhibiting a normal peak luminosity, it retains early-phase super-Chandrasekhar (03fg-like) characteristics: weak Fe III, narrow intermediate-mass element (IME), persistent carbon, and the absence of high-velocity Ca II features. Its nebular spectrum is unusually faint due to grey dimming beginning $\sim$60 days after maximum and shows [O I] emission, rare in SNe Ia. While a Chandrasekha…

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astro-ph.IMastro-ph.COcs.CVstat.AP

Neural Posterior Estimation for Tomographic Weak Lensing Mass Mapping

Tim White, Shreyas Chandrashekaran, Camille Avestruz, Jeffrey Regier, the LSST Dark Energy Science Collaboration

Weak gravitational lensing shear and convergence trace the distribution of baryonic and dark matter across space, making them a powerful probe of cosmic structure. Inferring shear and convergence from images is a challenging inverse problem. The prevailing approach to this task estimates shear from weighted averages of galaxy ellipticities, calibrates these estimates to account for systematic biases, and transforms them to reconstruct convergence, a multistage procedure that requires substantial…

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astro-ph.GAastro-ph.HE

A New Sample of $\sim$ 100 Intermediate-mass Black Holes Reaching $z \approx 1$

Wen-Juan Liu, Luis C. Ho, Su Yao, Xiao-Bo Dong, Yaqi Zhao

We present a systematic search for intermediate-mass black hole (IMBH) active galactic nuclei (AGNs) at $0.5 < z \lesssim 1$ using DESI DR1 spectroscopy.We identify 98 broad-line IMBH AGNs with black hole masses $M_\mathrm{BH}<10^6$ $M_{\odot}$ through quantitative spectral decomposition and broad-H$β$ selection. This sample spans $M_\mathrm{BH}=10^{5.5}-10^{6.0}$ $M_{\odot}$ and Eddington ratios from 1.2 to 9.0 extending systematic IMBH AGN searches to intermediate redshift. Compared with a con…

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astro-ph.GA

A Dusty Quenching-candidate AGN host at z=5.7: massive quiescent galaxies may quench already during the dust-obscured phase

Francesco D'Eugenio, Matilde Brazzini, Roberto Maiolino, Elena Bertola, Stefano Carniani, Xihan Ji, Ignas Juodžbalis, Yixiao Liu et al.

We present a spectro-photometric analysis of RUBIES-EGS-9809, a broad-line AGN host at z=5.7 with a Balmer break and a dominant point source. The source is dust reddened ($A_V>$3 mag), shows hot- and cold-dust emission, and is X-ray Compton thick, with X-ray-to-bolometric ratio consistent with luminous AGN. The large $A_V$ agrees with strong NaI absorption (EW=17$\pm 2 Å$), possibly from a neutral-gas outflow (3 $σ$), while broad [O III] traces an ionized outflow, suggesting AGN feedback may be…

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astro-ph.GAastro-ph.IM

The MICADO first light imager for the ELT: Simulated Observations of Star Forming Clumps at Cosmic Noon

Matteo Simioni, Carmelo Arcidiacono, Andrea Grazian, Marco Gullieuszik, Elisa Portaluri, Alvio Renzini, Benedetta Vulcani, Anita Zanella et al.

Galaxies at redshift z$\sim$2-6 exhibit prominent star-forming regions (clumps). Characterisation of these galactic structures requires both high sensitivity and spatial resolution of $\sim$100 pc or less. Currently, these spatial scales are achievable only with the aid of strong gravitational lensing. However, lensing introduces model-dependent uncertainties and limits the sample to galaxies behind massive clusters. The upcoming 40m-class telescopes, such as the ESO Extremely Large Telescope (E…

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astro-ph.EP

Sea Ice as an Origin of Life Location for Hycean and Ocean Worlds

Edouard F. L. Barrier, Nikku Madhusudhan, Frances E. Rigby

Water worlds with potential deep oceans are at the forefront of currently observable exoplanetary habitability. The standard requirements for habitability are the presence of an energy source, a source of nutrients, and a solvent, all of which can be met in exoplanets with deep liquid water oceans. Such planets may be numerous, ranging from hycean worlds and ocean worlds to terrestrial-size planets with enhanced water content. However, abiogenesis requires additional conditions, namely a mechani…

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astro-ph.HEphysics.plasm-ph

Two-Phase Structure of Synchrotron-Cooling-Unstable Relativistic Plasma

Agnieszka Wierzchucka, Pablo J. Bilbao, Robert J. Ewart, Dmitri A. Uzdensky, Alexander A. Schekochihin

Using analytic theory, radiative particle-in-cell (PIC) simulations, and fluid simulations, we show that relativistic, synchrotron-cooling, collisionless, high-$β$ pair plasmas filament into a two-phase medium. This process occurs through the interplay of the synchrotron cooling instability (SCI) with the synchrotron firehose instability (SFHI). One phase has high plasma~$β$ and is infested with small-scale firehose fluctuations, which scatter particles and pin the pressure anisotropy to the fir…

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astro-ph.IMastro-ph.HEgr-qc

Search for Long-Transient Gravitational Waves from Supernova SN2023ixf using GFH-v2 Pipeline

Sandhya Sajith Menon, Lorenzo Pierini, Pia Astone, Cristiano Palomba, Francesco Safai Tehrani, Lorenzo Silvestri, Ornella Juliana Piccinni, Simone Dall'Osso et al.

We present a directed search for long-transient gravitational waves from the possible newborn magnetar remnant of SN2023ixf, a nearby Type II core-collapse supernova in the M101 galaxy. The analysis uses LIGO Hanford and Livingston data from Engineering Run 15, using coincident data lying within the on-source window associated with the supernova. We target signals from a rapidly rotating, non-axisymmetric neutron star whose spin-down is dominated by gravitational-wave emission, producing a power…

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astro-ph.IMastro-ph.HEgr-qc

Search for Long-Transient Gravitational Waves from Supernova SN2023ixf using GFH-v2 Pipeline

Sandhya Sajith Menon, Lorenzo Pierini, Pia Astone, Cristiano Palomba, Francesco Safai Tehrani, Lorenzo Silvestri, Ornella Juliana Piccinni, Simone Dall'Osso et al.

We present a directed search for long-transient gravitational waves from the possible newborn magnetar remnant of SN2023ixf, a nearby Type II core-collapse supernova in the M101 galaxy. The analysis uses LIGO Hanford and Livingston data from Engineering Run 15, using coincident data lying within the on-source window associated with the supernova. We target signals from a rapidly rotating, non-axisymmetric neutron star whose spin-down is dominated by gravitational-wave emission, producing a power…

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astro-ph.HEgr-qc

Bridging the Population Synthesis of Supermassive Binary Black Holes and the Gravitational Wave Background

Kanyuni Iemoto, Boris Goncharov, Gabriela Sato-Polito, Xiaoming Bi

Pulsar Timing Arrays (PTAs) constrain population properties of supermassive binary black holes (SMBHBs) through the observation of the gravitational wave background (GWB). Unlike other approaches that interpolate population-synthesis libraries or only consider the mean of the strain spectrum, here we capture its full strain probability density directly from semi-analytic population models. We apply our new method to the semi-analytic SMBHB population model, independently reproducing the paramete…

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astro-ph.GAgr-qc

Improving constraints on the Yukawa correction at the Galactic Center with multiple stellar orbits

GRAVITY+ Collaboration, :, A. Foschi, K. Abd El Dayem, N. Aimar, A. Berdeu, J. -P. Berger, G. Bourdarot et al.

We investigate the presence of a Yukawa-like correction ($\propto \, αe^{- r/λ}$) to Newtonian gravity at the Galactic Center, using a multi-star fitting code, including the newly discovered star S$301$, to improve the constraints obtained using S$2$ orbit alone. We perform a Markov Chain Monte Carlo analysis using the astrometric and spectroscopic data of stars S$2$, S$55$, S$29$, S$38$ and S$301$ collected by GRAVITY, GRAVITY$^+$, NACO and SINFONI instruments, covering the period from $1992$ t…

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astro-ph.GAgr-qc

Improving constraints on the Yukawa correction at the Galactic Center with multiple stellar orbits

GRAVITY+ Collaboration, :, A. Foschi, K. Abd El Dayem, N. Aimar, A. Berdeu, J. -P. Berger, G. Bourdarot et al.

We investigate the presence of a Yukawa-like correction ($\propto \, αe^{- r/λ}$) to Newtonian gravity at the Galactic Center, using a multi-star fitting code, including the newly discovered star S$301$, to improve the constraints obtained using S$2$ orbit alone. We perform a Markov Chain Monte Carlo analysis using the astrometric and spectroscopic data of stars S$2$, S$55$, S$29$, S$38$ and S$301$ collected by GRAVITY, GRAVITY$^+$, NACO and SINFONI instruments, covering the period from $1992$ t…

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astro-ph.IMastro-ph.GAastro-ph.HE

Approximating the statistics of a gravitational wave background

Mikel Falxa

The astrophysical origin of the gravitational wave background (GWB) reported by pulsar timing array (PTA) collaborations has yet to be confirmed. A GWB signal made of the sum of individual gravitational wave (GW) from the population of supermassive black hole binaries (SMBHB) would show the imprint of a discrete Poissonian statistics in its spectral properties. In this work, we propose a tool based on the saddlepoint approximation method to estimate the distribution of characteristic strain for…

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astro-ph.SRphysics.atom-phphysics.plasm-ph

R-matrix calculations for opacities: V. Temperature-density dependence of photoabsorption cross sections and opacity spectra of oxygen ions O VI and O VII

Divya Chari, Sultana N Nahar, Anil K Pradhan

We present R-matrix photoabsorption cross sections for Li-like oxygen O VI and He-like oxygen O VII and examine how plasma broadening modifies them as a function of temperature and density in astrophysical and laboratory high-energy-density (HED) plasma sources. All atomic systems are subject to plasma environment effects, and the propagation of radiation depends on photoabsorption via bound-bound transitions as spectral lines and autoionizing resonances in bound-free photoionization cross secti…

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astro-ph.HE

Interior Magnetic Fields in Magnetars and Radio Pulsars

Raj Kishor Joshi, Brynmor Haskell, William Cook, Sebastiano Bernuzzi

Magnetic fields are fundamental for neutron star physics and play a central role in powering the extreme phenomenology of magnetars, including Soft Gamma Repeaters and Anomalous X-ray Pulsars. However, the structure and stability of their internal magnetic fields remain largely unconstrained, as they cannot be directly probed by electromagnetic observations. Using 3D general-relativistic magnetohydrodynamics simulations across a range of rotation rates and magnetic field strengths, we identify t…

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astro-ph.SRphysics.space-ph

Amplification of active region equatorial dipole

Ismo Tähtinen

The effect of active region parameters on the evolution of solar axial dipole is well understood. However, their effect on the solar equatorial dipole has not been studied in detail. Understanding the development of the equatorial dipole is important as it drives the interplanetary magnetic field on intracyclic timescales (~ 1yr). We study how the latitude, tilt angle, and the polarity separation affect the evolution of solar equatorial dipole. We use dipole flux transport (DFT), a matrix implem…

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astro-ph.GA

A new clump-based star formation model for galaxy simulations: implications for high-redshift compact star clusters

Shu Horie, Hidenobu Yajima

We develop a new star formation model for galaxy simulations in which star-forming gas clumps are identified on-the-fly and converted into stars with an efficiency $ε_{\rm SF}$ set by the clump surface density $Σ_{\rm c}$, calibrated against radiation hydrodynamics simulations of star cluster formation. Applying this model to isolated disc galaxies embedded in haloes of $M_{\rm h}=10^{9}$, $10^{10}$ and $10^{11}\,\mathrm{M_\odot}$, with disc compactness corresponding to redshift $z=0$--$10$, we…

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astro-ph.HEastro-ph.IM

A cosmic-ray database update: CRDB v4.2

Davud Maurin

The cosmic-ray database, CRDB, has provided data and meta-data to the community since 2013. We present a new release, CRDB v4.2, which includes data and time series published in the last three years (from AMS-02, CALET, DAMPE, LHAASO, etc.), datasets missed in previous releases, and all peer-reviewed ultra-high energy cosmic-ray data (both historical and recent datasets). These data and meta-data are available from the web interface or from the CRDB pip-installable Python library. This release i…

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astro-ph.IMphysics.space-ph

Optical Flashes from Beam-Driven Light Sails with the Roman, Rubin and Euclid Observatories

James Guillochon, Abraham Loeb

The primary challenge of rocket propulsion is the burden of accelerating the spacecraft's own fuel. Light sails leave the propellant at home, with the achievable speed set by the sail area, the thermal tolerance of its material, and the power of the driving array. In GL15 we showed that leakage from a microwave array driving such a sail between habitable worlds produces Jansky-level radio transients lasting tens of seconds at $100$~pc. We take that leak to optical and near-infrared, where Fresne…

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