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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.EP

JWST NIRCam Reveals the Largest Known M-dwarf Debris Disk Around TWA 10 and New Scattered-Light Observations of the TWA 25 Debris Disk

Katie A. Crotts, Aarynn L. Carter, Beth Biller, Mark Booth, Rachel Bowens-Rubin, Raphaël Bendahan-West, Rodrigo Ferrer-Chavez, Kellen Lawson et al.

We present JWST NIRCam observations of two M-dwarf systems located in the TW Hydra association, TWA 10 and TWA 25. Both systems harbor detected debris disks in the F200W and F444W filters. Whereas the TWA 25 disk has been previously imaged, these observations represent the discovery and first images of the TWA 10 disk. In addition to planet searches within these systems, we also conduct an analysis of each debris disk, where the TWA 10 debris disk is characterized for the first time. We find tha…

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astro-ph.SRastro-ph.EP

Spin-spin coupling in stellar binaries

Alexandre C. M. Correia

Spin-orbit misalignment is increasingly observed in binary stars, but its origin remains uncertain. We study the secular spin dynamics of stellar binaries and derive the associated Cassini states. We isolate a spin-spin resonance that arises when the two stellar spin-precession frequencies become commensurate. This resonance can excite the obliquity of the secondary to high values even when the primary is only weakly tilted. Magnetic braking favors the formation of high-obliquity states, whereas…

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astro-ph.HEastro-ph.GA

Winds Versus Jets in Active Galactic Nuclei

David Garofalo, Chandra B. Singh, Atticus Magerko, Marco Botello, Sophia Soto, Max North

The well-established anti-correlation between disk winds and relativistic jets in X-ray binaries is often interpreted in a scale-invariant black hole accretion context. If so, active galactic nuclei (AGN) should exhibit a direct mass-scaled analog. We test this prediction across FRII radio quasars, radio-quiet quasars, and jetted and non-jetted Narrow Line Seyfert 1 galaxies (NLS1) in spirals, among others. They exclude simple scale invariance. The highest-velocity winds occur exclusively in rad…

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astro-ph.IMastro-ph.GAastro-ph.SR

HRMOS: a very high-resolution, multi-object spectrograph for the ESO VLT

Andrea Bianco, Sofia Randich, Emma Fernandez Alvar, Oscar Gonzalez, Sergio Sousa, Thomas Bensby, Letizia Caito, Enrico Giro et al.

HRMOS (High-Resolution Multi-Object Spectrograph) is a proposed new instrument for the ESO Very Large Telescope (VLT) developed in the context of the ESO VLT Beyond 2030 call. It is designed to fill a unique and currently unoccupied region in the observational landscape: the combination of very high spectral resolution (R=80,000) with multi-object capability (50-60 simultaneous targets), a radial-velocity (RV) precision of 10m/s, and coverage of three key spectral windows (385-421nm, 480-522nm,…

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astro-ph.EPastro-ph.SR

A closer look at the WISPIT 2 host star. Evidence for a spectroscopic binary

Cade J. Bürgy, Myriam Benisty, Hala Alqubelat, Carlo F. Manara, Stefano Facchini

While hundreds of protoplanetary discs have been studied in great detail, the detection of protoplanets still embedded in their native discs remains rare. WISPIT 2 is only the second laboratory allowing for direct study of planet formation while in progress. The recently discovered system hosts two giant protoplanets in a multi-ringed disc. Here, we aim at characterising the WISPIT 2 host star spectroscopically to determine its stellar properties, accretion rate, and inner disc diagnostics, prov…

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astro-ph.HEastro-ph.IM

4th TDAMM Workshop White Paper

Daniel Kocevski, Raffaella Margutti, Michael Coughlin, Christopher Fryer, Kate Alexander, Igor Lorenzo Andreoni, Jean-Luc Atteia, Elias Aydi et al.

Time-Domain and Multi-Messenger Astrophysics (TDAMM) is entering a new era in which the rate and diversity of transient discoveries will grow rapidly across electromagnetic, gravitational-wave, neutrino, and cosmic-ray facilities. The scientific return from these investments will increasingly depend not on discovery alone, but on the ability to identify, prioritize, and coordinate follow-up observations across a heterogeneous and globally distributed network of observatories. This white paper su…

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astro-ph.IM

ANDES, the high-resolution spectrograph for the ELT: design and performance analysis of the YJH spectrograph

Vinooja Thurairethinam, David Lee, James Stevenson, Étienne Artigau, Frédérique Baron, Ciarán Breen, Bella Boyd, Denis Brousseau et al.

The ArmazoNes high Dispersion Echelle Spectrograph (ANDES) is a powerful second-generation high-resolution spectroscopic instrument for the Extremely Large Telescope (ELT). The UBV, RIZ, and YJH modules comprise fibre-fed spectrographs of the ANDES baseline design and will offer continuous wavelength coverage of 0.35-1.8 $μ$m, with the addition of a K-band channel providing coverage up to 2.4 $μ$m. Coupled with a spectral resolution of $\sim$100,000, ANDES must deliver the required wavelength ca…

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astro-ph.IM

ANDES, the high-resolution spectrograph for the ELT: design and performance analysis of the YJH spectrograph

Vinooja Thurairethinam, David Lee, James Stevenson, Étienne Artigau, Frédérique Baron, Ciarán Breen, Bella Boyd, Denis Brousseau et al.

The ArmazoNes high Dispersion Echelle Spectrograph (ANDES) is a powerful second-generation high-resolution spectroscopic instrument for the Extremely Large Telescope (ELT). The UBV, RIZ, and YJH modules comprise fibre-fed spectrographs of the ANDES baseline design and will offer continuous wavelength coverage of 0.35-1.8 $μ$m, with the addition of a K-band channel providing coverage up to 2.4 $μ$m. Coupled with a spectral resolution of $\sim$100,000, ANDES must deliver the required wavelength ca…

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astro-ph.SR

Detection of pulsations and a non-stable wind in IRAS 01005+7910, an object with the B[e]-phenomenon

Anatoly S. Miroshnichenko, Valentina G. Klochkova, Vladimir E. Panchuk, Ekaterina S. Islentieva

Comparison of the spectra obtained at different observing dates shows significant variations in the complex H$α$ and H$β$ line profiles, such as a systematic increase in their emission peak strengths in 2025$÷$2026 compared to those observed in 2013 as well as a strong variability in their wind component. A detected variable radial velocity $V_{\odot}$ from $-20$ to $-68$ km/s with a standard deviation of the mean value of K$\sim$8.0 km/s can be interpreted as a result of pulsations or the prese…

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hep-exastro-ph.HE

Proton-air interaction properties at $\sqrt{s} \simeq 100$ TeV from shower-depth measurements with the Pierre Auger Observatory and their connection to the Muon Puzzle

The Pierre Auger Collaboration, A. Abdul Halim, P. Abreu, M. Aglietta, M. Ahmed, I. Allekotte, K. Almeida Cheminant, R. Aloisio et al.

Hybrid measurements at the Pierre Auger Observatory indicate that most high-energy hadronic interaction models underestimate the average depth of the shower maximum, $\langle X_{\max} \rangle$, at a center-of-mass energy of $\sqrt{s}=97.7 \pm 0.4^{+6.6}_{-6.2}\,\mathrm{TeV}$. In this Letter, the hadronic interaction models are shown to follow a universal relation between the predicted $\langle X_{\max} \rangle$ and the mean values of variables characterizing the energy spectra of secondary parti…

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astro-ph.SRastro-ph.HE

Discovery of a radio-flaring M dwarf in a commensal transient search of the LADUMA field

Moses Mlangeni, Patrick A. Woudt, Paul J. Groot, Alex Andersson, Zwidofhela N. Khangale, Francesco Cavallaro, Steven Bloemen, Paul Vreeswijk et al.

We report the discovery and characterisation of MKT J032848.4-271904.6, a new radio transient identified in the LADUMA field using SARAO Science Data Processor (SDP) UHF-band images from approximately one year of MeerKAT observations. Using the Transient Pipeline (TraP) and advanced filtering techniques, we identified a number of candidate variable radio sources in the field. All but one show variability consistent with refractive interstellar scintillation, leaving MKT J032848.4-271904.6 as the…

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astro-ph.IM

METIS for ELT: optical alignment and testing of the IFU of the LM-band spectrometer

Lawrence Bissell, Éamonn Harvey, Stephen Todd, Valentina Oyarzun, Alastair Macleod, Sandi Wilson, Alistair Glasse, Daniel Dicken et al.

The METIS LMS (LM-band Spectrometer) is a high-resolution (R>100,000) mid-infrared integral field spectrometer for the ESO ELT. The instrument provides the capability to measure instantaneous spectra across a 0.577 x 0.897 arcsecond field-of-view with a spatial sampling of 8.2-9.1 mas using an image slicing IFU. This paper presents the optical testing and alignment performed for the IFU sub-system. This includes the detailed characterisation of the image slicing mirror array measured via: a re-i…

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astro-ph.SRastro-ph.GA

Ensemble Kinematic Ages for 1.5 Million LAMOST Stars

Yuxi Lu, Marc H. Pinsonneault

We present a framework for inferring stellar ages from spectroscopic stellar parameters, calibrated with ensemble kinematics by averaging over the median vertical action, $J_z$, for stars with similar atmospheric and chemical properties, yielding self-consistent age estimates across the Hertzsprung-Russell (HR) diagram. We refer to these ages as ensemble kinematic ages as the age scale is calibrated from the average kinematics of ensembles of stars with similar stellar parameters. Individual ste…

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astro-ph.IM

CUBES: optical design and analysis of the VLT's high-resolution UV spectrograph past final design review

Lawrence Bissell, Walter Seifert, Ariadna Calcines Rosario, Hans Dekker, Gerardo Avila, Luca Oggioni, Giorgio Pariani, Matteo Genoni et al.

CUBES (Cassegrain U-Band Efficient Spectrograph) will be the most efficient UV spectrograph on an 8-10m class telescope, exploiting the ESO VLT's higher telescope efficiency relative to the ESO ELT in ground-based UV wavelengths. The instrument provides wavelength coverage over a range of 300-405nm, with high instrumental efficiency (>37%) and a resolving power of >20,000 (HR) and >6,000 (LR). It will be mounted on the Cassegrain focus of the VLT in Paranal. This paper presents the optical desig…

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astro-ph.HEastro-ph.SR

Exploring the optical properties of redback pulsars: The case of J1717+4308A in the globular cluster M92

Jianxing Chen, Greta Ettorre, Cristina Pallanca, Mario Cadelano, Bidisha Sen, Devina Misra, Emanuele Dalessandro, Francesco R. Ferraro et al.

Binary millisecond pulsars (MSPs) in globular clusters (GCs) are key for binary and stellar evolution studies under extreme conditions. The identification of their optical companion stars is instrumental in order to characterise these systems and to constrain the possible recycling mechanisms. For this work, we searched for the optical counterpart to PSR J1717+4308A (hereafter M92A) in the GC M92. To this end, we exploited a multi-epoch, multi-wavelength dataset obtained with the Hubble Space Te…

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astro-ph.IM

HARMONI at ELT: LPOU calibrations for a micron-level pointing accuracy

Gonzalo José Carracedo Carballal, Irene Ferro Rodríguez, David L King, Iago Funes Vecino, Guillermo Mercant Rubio, Alonso Álvarez Urueña, Laura García Moreno, Heribert Argelaguet Vilaseca et al.

HARMONI is the first light, adaptive optics assisted, near-IR integral field spectrograph for the ELT [1]. It covers a spectral range from 800 nm to 2450 nm with resolving powers from 3000 to 7000 and spatial sampling of 25 mas and 6mas. It can operate in two adaptive optics modes, SCAO (including a high contrast capability) and MCAO. The project is resuming its final design phase after a rescope design phase in 2025. To achieve its optimal image quality, HARMONI needs to perform pointing error…

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astro-ph.IM

HARMONI at ELT: Design & Test on the current status of Low Order Wavefront Subsystem Pick Off Arm Engineering Model (LPOA-EM)

Iago Funes Vecino, Guillermo Mercant Rubio, Alonso Álvarez Urueña, Laura García Moreno, Gonzalo José Carracedo Carballal, Irene M. Ferro Rodríguez, Heribert Argelaguet Vilaseca, Javier Piqueras López et al.

HARMONI is the first-light, adaptive-optics-assisted, near-infrared integral field spectrograph for the ELT, covering 800 to 2450 nm with resolving powers from 3000 to 7000. The Low Order Wavefront Sensor subsystem (LOWFS) provides field stabilisation by measuring the motion of the instrument focal plane relative to the telescope wavefront sensors. Following a rescope process in 2025, LOWFS has been updated to operate three LOWFS Pick-Off Arms (LPOA) simultaneously within a shared volume. We pre…

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astro-ph.GA

When Two Worlds Collide: How Collisions Between Silicate and Carbonaceous Nanograins can Drive Complex Chemistry

Alexandros Kyriazis, Albert Rimola, Stefan T. Bromley

Our overall objective is to determine how collision velocity governs the interactions between silicate and carbonaceous nanograins. We aim to: i) identify collisional regimes capable of producing mixed silicate-carbonaceous grains and/or chemically complex molecular species, and ii) quantify fragmentation threshold velocities related to dust destruction. We performed molecular dynamics simulations employing a machine-learning force field to model head-on collisions between silicate and carbonace…

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astro-ph.EP

Information content on Venusian aerosols in VIRTIS-M infrared data

Jaime Reyes-Guerrero, Santiago Pérez-Hoyos, Itziar Garate-Lopez

Venus presents a complex cloud structure with aerosol particles of different sizes located mainly between 48 km and 70 km in altitude. However, the number of free parameters that can describe such a cloud structure is usually overwhelming, and a number of simplified parameterizations are commonly assumed. In this work, we re-analyze the information content on aerosol vertical distribution provided by the nightside infrared data collected by VIRTIS instrument onboard Venus Express. Starting from…

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astro-ph.EPastro-ph.IM

First results of a continuous monitoring campaign of the PLATO Southern field

Thomas Granzer, Jorg Weingrill, Klaus G. Strassmeier, Arto Jarvinen

The BMK10k project started as an ancillary project to the PLATO ESA mission, dedicated to photometrically monitor the PLATO Southern field, to help with source confusion, and to mitigate the problem of false-positive exoplanet detections. Planned as a long-term project, the BMK10k should see an operational time-scale in the order of a decade, well above the proposed PLATO operational phase. Thus, BMK10k may help resolving single- event transit issues detected with PLATO and may be in the unique…

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astro-ph.HE

Observation of Wobbling and Precessing Jet Signatures in Gamma-Ray Emission from Blazar PKS 1424-41

Ajay Sharma, Debanjan Bose

We report a clear observational evidence for jet precession and nutation manifested in the gamma-ray emissions of the blazar PKS 1424$-$41. An analysis of $\sim$16 yr of \emph{Fermi}-LAT observations reveals three distinct and superimposed quasi-periodic oscillations (QPOs), with characteristic timescales of $\sim$5.26 yr, $\sim$0.96 yr and $\sim$1.3 yr. The longer timescale is detected with a local significance of $\sim 4.1σ$ ($99.9958\%$ confidence) and a global significance of $\sim 2.45σ$ ($…

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astro-ph.EP

Dust characterization of the HD 163296 disk with high-resolution multi-wavelength ALMA observations

Kiyoaki Doi, Myriam Benisty, Akimasa Kataoka, Haochang Jiang, Francesco Zagaria, Hauyu Baobab Liu, Carsten Dominik, Ryo Tazaki et al.

Context. Planets form through the growth and accumulation of dust grains in protoplanetary disks. Characterizing dust properties such as size, surface density, and temperature is key to understanding planet formation. Aims. We characterize the dust properties of the protoplanetary disk around HD 163296 by performing spectral energy distribution (SED) fitting of multi-wavelength high-resolution observations. Methods. We present new high-resolution ALMA Band 9 (0.45 mm) observations, which are sen…

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astro-ph.IM

LEO-to-ground low elevation optical communication: optimization of an adaptive optics design robust to scintillation

Timoth{é}e Vene, Aur{é}lie Montmerle-Bonnefois, Laurent Mugnier, Jean-Marc Conan

To maximize the duration of optical downlinks with Low-Earth Orbit satellites, it is crucial to ensure the coupling into the single mode fiber of the ground terminal even at low elevations. Adaptive optics systems are designed to correct the wavefront deformation induced by atmospheric turbulence. However, at low elevations, amplitude fluctuations (or scintillation) challenge this correction. Here we propose a methodology to design a wavefront sensor that is robust to scintillation, taking the S…

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astro-ph.SR

Population synthesis of delta Scuti stars: the instability strip, period-luminosity relation, and large-separation distribution

Simon J. Murphy, Anuj Gautam

Interpreting the observed properties of intermediate-mass stars requires accounting for rotation, binarity, intrinsic population diversity, and measurement uncertainty. We combine these effects in population-synthesis models of 1.4-2.5 M$_{\odot}$ stars that include pulsation properties of $δ$ Sct variables. The synthetic populations successfully reproduce the distributions of stars observed in young associations, validating the mapping between intrinsic and observed stellar properties. Using th…

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astro-ph.HE

Revealing Four Subpopulations of Binary Black-Hole Mergers with the Fifth Gravitational-Wave Transient Catalog

Nir Guttman, Paul D. Lasky, Eric Thrane

Gravitational-wave data are beginning to reveal a structured landscape of black-hole masses and spins, suggesting multiple formation processes are now being resolved observationally. We analyze data from LIGO--Virgo--KAGRA's (LVK's) fifth Gravitational-Wave Transient Catalog and find that the population is naturally described by four distinct subpopulations. The dominant component, contributing $\simeq70\%$ of the astrophysical merger rate, is characterised by a low-mass population centred near…

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astro-ph.GA

Kinematic scaling of thin and thick discs from SAMI to NewHorizon

Sree Oh, J. K. Jang, Giulia Santucci, Sukyoung K. Yi, Matthew Colless, Scott M. Croom, Yohan Dubois, Stefania Barsanti et al.

We revisit the relation between disc stellar mass and disc velocity dispersion (M_*-σ_e) and extend it to thin and thick subcomponents using orbit-based dynamical models of 161 SAMI galaxies and counterpart measurements for 31 disc galaxies in the NewHorizon simulation. On the observational side, we apply Schwarzschild orbit superposition to recover orbital circularity distributions and component kinematics. On the simulation side, we sample thin and thick discs by circularity and, separately, b…

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astro-ph.HE

A post-hypercritical accretion small-scale dynamo in newborn neutron stars

David F. Bambague, Cristian G. Bernal, J. A. Rueda

Hypercritical fallback accretion can advect the surface magnetic field of a newborn neutron star into the newly accreted outer layers. Before this material joins the solid crust and enters the Hall-Ohmic regime, part of it may remain hot, dense, and liquid, allowing turbulent magnetic amplification. We investigate whether a small-scale dynamo (SSD) can operate under these conditions using six local 3D resistive MHD simulations performed with FLASH 4.7 in a periodic domain with externally forced…

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astro-ph.HEastro-ph.GA

Radio Core Size of Low-luminosity Active Galactic Nuclei under the MAD-jet model

Yue Xu, Fu-Guo Xie

After decades of efforts, there are now fruitful high-resolution radio observations of low-luminosity active galactic nuclei (LLAGNs), and the observed frequency has extended from $\sim$10 GHz up to $\sim$200 GHz. In this work, based on a model that combines a magnetically arrested disk (MAD) and a Blandford-Znajek-like jet, we carried out detailed analysis on size and location of the radio core of LLAGNs. The radio core size of nearby LLAGN M104 is re-visited based on this new model. We success…

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astro-ph.HEastro-ph.GA

The Distinctive Evolution and Spectral Energy Distribution of Binary Massive Black Hole Accretion

Yue Xu, Fu-Guo Xie, Ya-Ping Li, Yinhao Wu, Luis C. Ho

Binary (super-)massive black holes (BHs) are expected to reside in the center of some galaxies. In this work, we re-visit accretion onto binary massive BHs, incorporating recent advances in both accretion theory and the mass transfer rate between the two massive BHs. We focus on relatively bright systems with an Eddington ratio of 0.1 for a binary with total BH mass $10^8\,M_\odot$, but consider a wide range of mass ratios $10^{-4} \le q \le 0.5$. The binary system consists of two mini-disks sur…

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astro-ph.EP

A Stable Mineral Fingerprint in the Fading Warm Debris Disk around HD 15407A

Shu Wang, Zhuochao Huang, Xiaodian Chen, Junming He, Haomiao Huang

Extreme debris disks provide time-domain probes of rocky planet assembly after giant impacts. We compare Spitzer and JWST spectra of the warm debris disk around HD 15407A, obtained 14.95 yr apart. Across 6-25$μ$m, the stellar-subtracted mid-infrared excess declined by $14.0\pm1.2$%, while the mineral fingerprint is nearly unchanged. Within the adopted common reduced mineral basis, Mg-rich pyroxene dominates the normalized fitted mineral weights at about 65%, while silica and forsterite contribut…

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