研究動向

astro-ph.GAastro-ph.SR2026年7月17日

A JWST, ALMA and VLA survey of the Ophiuchus-A star-forming region: Unveiling hidden dust mass and connecting infrared outflows to their radio origins

Isaac C. Radley, John D. Ilee, Gemma Busquet, Hauyu Baobab Liu, Klaus M. Pontoppidan, Alvaro Ribas, Marc Audard, Eleonora Bianchi et al.

We present an infrared, millimetre, and radio survey of 20 Class 0-III young stellar objects in the Ophiuchus A L1688 star-forming cluster, combining high-resolution (7-25 au) VLA and JWST observations with archival ALMA data. We implement physically motivated models to derive dust and ionised gas properties, spectral behaviour and their relative contributions through the millimetre-centimetre radio spectral energy distribution. Our models reveal circumstellar dust disks that are, on average, te…

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astro-ph.HEastro-ph.SR2026年7月17日

Implications of the UV/optical Plateau of AT2018cow

Wenbin Lu, Anthony L. Piro

AT2018cow, the prototypical luminous fast blue optical transient (LFBOT), shows a slowly fading plateau in the UV/optical light lasting at least 5 years after the explosion. The plateau SED is blackbody-like with temperature $\gtrsim$ 2e4 K and an emission radius ~40 Rsun, which has been attributed to a geometrically thin accretion disk around a compact object. Viscously powered disk models, however, require an unusually massive black hole $\gtrsim$ 200 Msun (for viscosity parameter $α$ > 0.01).…

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astro-ph.HE2026年7月17日

Assessing the waveform systematics from parameter estimation to population inference with eccentricity

Muhammad Zeeshan, Richard O'Shaughnessy, Natalie Malagon, Katelyn J. Wagner

While masses and spins are routinely used to constrain compact binary formation channels, eccentricity provides an additional and potentially powerful diagnostic of binary origin, particularly for dynamically assembled systems. Recent advances in eccentric waveform modeling now make it possible to search for eccentric signatures in gravitational wave data; however, differences between waveform models can introduce systematic effects that may propagate into astrophysical population inference. In…

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astro-ph.HE2026年7月17日

Triple radio flares from tidal disruption events: jet-wind collisions and the discovery of a third radio flare from AT2020vwl

Andrew Mummery, Adelle Goodwin, Colin Christy, Kate Alexander, Noah Franz

Radio flares from tidal disruption events (TDEs) are observed on two distinct timescales: prompt (around the time of optical peak) and delayed (hundreds to thousands of days after optical peak). A recent framework put forward to explain this diversity suggests that super-Eddington winds produce prompt flares while jets launched during a disk state transition at low accretion rates produce delayed flares. A unique observational prediction of this framework is that individual sources showing both…

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astro-ph.HE2026年7月17日

A Multiwavelength Study of a Long-Duration VHE Flare from BL Lacertae with VERITAS

Atreya Acharyya, Avery Archer, Priyadarshini Bangale, Joshua Bartkoske, Wystan Benbow, James Buckley, Yu Chen, Jodi Christiansen et al.

We report the first observations of a long-duration very-high-energy (VHE; $E > 100$ GeV) flare from BL Lacertae (VER J2202+422), taken with the Very Energetic Radiation Imaging Telescope Array System (VERITAS). On October 15, 2022, the Fermi-Large Area Telescope (LAT) detected elevated GeV activity originating from this blazar. This triggered a multiwavelength campaign, which includes observations from VERITAS, Swift, NuSTAR, and select optical and radio observatories. VERITAS observed the sour…

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astro-ph.HE2026年7月17日

Uncovering Hierarchical Sub-Population of Binary Black Holes

Muhammad Zeeshan, Richard O'Shaughnessy

Enabled by improved instruments with increasing sensitivity, the ongoing gravitational wave census now contains 259 binary black holes, numerous enough to unveil trends, substructure, and subpopulations which may provide key clues to their underlying formation mechanisms. In this work, motivated by evidence for multiple formation channels including hierarchical formation, we build a natively multi component mixture model for the binary black hole population, in which each component has an indepe…

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astro-ph.SR2026年7月17日

Pre-main Sequence B Stars Surrounding the Orion Nebula

P. H. F. B. Braz, A. Roman-Lopes, W. J. B. Corradi, E. B. Amôres, M. S. Angelo, F. S. S. Maia, J. F. C. Santos, A. E. Piatti et al.

Pre-main sequence (PMS) early-type stars are rare due to their rapid evolution. Confirming PMS B stars is accordingly valuable for constraining higher mass star formation scenarios. Although the Orion Nebula (ON) region offers an ideal laboratory for such studies, its population of B stars remains poorly characterized. We aim to determine spectral types, masses, and ages of B and early A stars surrounding the ON, to identify robust PMS candidates. We combine optical and near-infrared spectroscop…

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astro-ph.HE2026年7月17日

Large-scale emission from gamma-ray binaries: the case of LS 5039

J. R. Martinez, V. Bosch-Ramon

Abridged abstract: Context: Gamma-ray binaries hosting a non-accreting neutron star and a massive star exhibit multi-wavelength emission on different spatial scales. The interaction between their winds produces an outflow that can inflate a bubble or form a bow shock as it interacts with the surrounding medium. LS 5039 shows extended (1 pc-scale) X-ray emission that may arise from one of these large-scale structures. Aims: We explain and predict the large-scale emission from LS 5039. Methods: We…

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hep-phastro-ph.HEastro-ph.SRnucl-th2026年7月17日

Solar-System Abundances of $p$-Nuclides Probe Collective Neutrino Oscillations in Supernovae

Alexander Friedland, Derek J. Li, Giuseppe Lucente, Payel Mukhopadhyay, Ian Padilla-Gay, Amol V. Patwardhan

Direct evidence for collective neutrino oscillations in core-collapse supernovae remains elusive. We show that this quantum phenomenon leaves a footprint on the abundance pattern of proton-rich nuclides in the solar system. Modeling the $νp$-process using a $20\,M_\odot$ progenitor, we map out the dependence of the total yields on the starting radius of the oscillations, self-consistently coupling hydrodynamics and nucleosynthesis. The oscillations boost key $p$-nuclides ($^{92,94}\text{Mo}$, $^…

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astro-ph.EP2026年7月17日

Ephemeris Refinement for Qatar-4 b, HAT-P-18 b, and CoRoT-1 b with Small Telescope and TESS Observations

Heather B. Hewitt, Mikaela Chamlee, Trinity Hockman, Annalise Igyarto, Dan van der Burg, Federico R. Noguer, Ira Bell, Jeremie Abides et al.

We present updated transit timing measurements for three hot Jupiters (Qatar-4 b, HAT-P-18 b, and CoRoT-1 b) by leveraging data collected from the MicroObservatory Telescope Network, a network of small, robotic ground-based telescopes, and the NASA Transiting Exoplanet Survey Satellite (TESS). By combining these data with archival published results, we present the most precise orbital solutions to date for all three systems, allowing for precise transit time predictions for future missions. We r…

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astro-ph.SRastro-ph.HE2026年7月17日

Luminous Red Novae as shock-powered transients I: Electron-scattering wings and deviations from Case B

Albert Sneppen, Kenta Hotokezaka, Christopher M. Irwin

Luminous red novae (LRNe) are a class of optical transients resulting from the mergers of binary stars or common envelope events. The population displays heterogeneous light curves with extended luminosity plateaus and/or secondary peaks, suggested to be powered by hydrogen recombination or shocks between pre- and post-merger ejecta. However, much of their spectroscopic behaviour remains unexplained. Using a sample of six LRNe, we identify telltale spectral evidence for shock processes across th…

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astro-ph.IM2026年7月17日

Assembly, integration, and verification of MITESI: an optical testbed for simulating the ELT in the laboratory

Daniel J Ahrer, M. Concepción Cárdenas Vázquez, Thomas Bertram, Peter Bizenberger, Armin Huber, Raphaël Pourcelot, Silvia Scheithauer, Horst Steuer et al.

MITESI is an optical testbed which simulates key characteristics of the ELT, ultimately producing an artificial natural guide star. It was designed primarily to enable testing of the METIS instrument's SCAO system in closed loop. In this contribution, we discuss the assembly, integration and verification process of the testbed, taking the project from design to assembled hardware.

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astro-ph.SR2026年7月17日

Stellar heavy-element slope index

Gerd Roepke, Friedrich K. Roepke, David Blaschke

The distribution of heavy elements in stars is described using a phenomenological approach, in which Lagrange parameters related to temperature and the chemical potentials of protons and neutrons are introduced within a freeze-out concept. Slope parameters are considered which describe the gross behavior of the distribution of the heavy elements. Universality and deviations from universality are discussed, and various examples are provided. These slope parameters may be of interest for character…

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astro-ph.HEgr-qc2026年7月17日

Multimessenger prospects of quasi-periodic eruptions

Vojtěch Witzany, Alessia Franchini, Matteo Bonetti, Luca Broggi

Quasi-Periodic Eruptions (QPEs) are recurring soft X-ray transients that may be generated by inspirals of stellar-mass objects spiraling into supermassive black holes, known as extreme mass ratio inspirals (EMRIs). Independently, EMRIs and the gravitational-wave signals they generate are one of the key targets for the Laser Interferometer Space Antenna (LISA). What is the potential of a coincident detection of EMRIs both as a QPE and by LISA? Electromagnetic counterparts to LISA events would pro…

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astro-ph.HEastro-ph.GA2026年7月17日

Observations of X-ray quasi-periodic eruptions

Thomas Wevers, Joheen Chakraborty, Erwan Quintin, Michal Zajaček, Margherita Giustini

Quasi-periodic eruptions (QPEs) are a novel class of repeating nuclear transients, discovered exclusively in the X-ray band to date. Since their initial discovery in 2019, the QPE sample has grown to 13 sources, exhibiting large amplitude, quasi-regular eruptive variability patterns that are distinct from previously known modes of massive black hole variability. In this chapter, we provide a comprehensive overview of their observational characteristics. We review the X-ray spectral and timing pr…

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astro-ph.GAastro-ph.CO2026年7月17日

Non-Thermal Physics Drives Compact, Self-Regulated Galaxy Morphologies at Cosmic Dawn

Michelle S. Park, Sergio Martin-Alvarez, Risa H. Wechsler

James Webb Space Telescope (JWST) has discovered unexpectedly bright, rapidly growing galaxies in the early universe, which were not predicted by most previously existing galaxy formation models. Using synthetic JWST observations of the Azahar simulation suite, we show that comprehensive non-thermal physics ("Full-Physics") produces compact, self-regulated galaxies that match observations from $z = 12$ to $z = 3$. This model also produces broad surface brightness distributions, where the bright…

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astro-ph.EPastro-ph.GA2026年7月17日

Very Large Telescope observations of interstellar comet 3I/ATLAS III: High-resolution monitoring of CN and forbidden oxygen emission across the perihelion passage with ESPRESSO

Baltasar Luco, Thomas H. Puzia, Rohan Rahatgaonkar, Juan Pablo Carvajal, Prasanta K. Nayak

3I/ATLAS is only the third known interstellar object to traverse the Solar System. We obtained high-resolution ($R\simeq 140000$) spectroscopy of 3I/ATLAS on 23 nights with VLT/ESPRESSO ($r_{h}=1.67-2.45$au). CN production rates were derived by fitting the $B^2Σ^+-X^2Σ^+$ band, using CometSpec, a publicly released Python package for flexible fluorescence modeling. The three forbidden [OI] lines were modeled to derive the green-to-red (G/R) flux ratio and a CO$_2$/H$_2$O proxy. We fit $Q_{CN}=a(r…

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astro-ph.GA2026年7月17日

The first three-dimensional map of thermal phases in the local interstellar medium

Jonathan Shelest, Shmuel Bialy, Troy A. Porter, Mark Wolfire, Matan Berko, Margarita Grinberg

The thermal state of interstellar gas controls whether it remains warm and diffuse or cools into dense clouds. Twenty-one centimetre observations have established a statistical picture of neutral-gas phases, but their three-dimensional architecture has not previously been mapped. Here we present $\mathcal{P}_{\rm 3D}$, a three-dimensional reconstruction of thermal phase in the local interstellar medium (ISM), covering a 1 kpc-diameter region centred on the Sun and sampled on a 2 pc Cartesian gri…

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astro-ph.SRphysics.flu-dyn2026年7月17日

Polarization geometry of magnetohydrodynamic turbulence

Raphael Skalidis

We introduce a geometric framework that organizes the second-order statistics of the Elasser fields into polarization states on generalized Poincaré spheres. In this representation, energy, cross-helicity, residual energy, and the phase lag between counter-propagating wave packets emerge as complementary polarization parameters. We derive a Bloch-analogue equation governing the evolution of polarization states and show that distinct polarization geometries are associated with different cascade d…

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astro-ph.GAastro-ph.CO2026年7月17日

The Azahar Project: Non-Thermal Physics Drives Star Formation Burstiness and the Evolution of the UV Luminosity Density at Cosmic Dawn

Sergio Martin-Alvarez, Risa H. Wechsler, Debora Sijacki

JWST observations, which have pushed the discovery and characterization of galaxies to cosmic dawn, have revealed significant deficiencies in state-of-the-art galaxy formation simulations, motivating the need for novel, physically grounded models. We present the first results from the Azahar suite of ten high-resolution ($\sim$20 pc), large-volume zoom-in cosmological simulations, which follow the formation of thousands of galaxies and progressively incorporate radiative transfer (RT), cosmic ra…

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astro-ph.HE2026年7月17日

Ultraviolet to Infrared Spectroscopy of the Type Ibn SN 2023tsz Suggests a Lower-mass Progenitor

Sergiy S. Vasylyev, Griffin Hosseinzadeh, Luc Dessart, Ori Fox, David J. Sand, Alexei V. Filippenko, Qinan Wang, D. Andrew Howell et al.

Type Ibn supernovae are stripped-envelope explosions whose spectra indicate interaction with dense, helium-rich and hydrogen-poor circumstellar material (CSM), making them important probes of late-stage mass loss and progenitor stripping. We present extensive ultraviolet-to-near-infrared spectrophotometry of the Type Ibn SN 2023tsz, including two epochs of HST/STIS ultraviolet (UV) spectroscopy and ground-based optical and near-infrared follow-up observations. The spectra are dominated by interm…

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astro-ph.GA2026年7月17日

How large can galaxies be? Ultra-deep imaging of IC 1101, the most extended known galaxy

Carlos Marrero-de la Rosa, Ignacio Trujillo, Ignacio Ruiz Cejudo, Mireia Montes, Fernando Buitrago, Giulia Golini, Sergio Guerra Arencibia, Andrés Asensio Ramos et al.

The maximum physical extent that galaxies can reach is poorly understood. In this regard, IC 1101, one of the most extended and massive galaxies known, provides a valuable opportunity to constrain the upper limit of galaxy sizes at the present epoch. Previous deep imaging of the system confirmed its enormous extension, but did not indicate whether it has an edge. We explore this issue using the deepest images ever taken of this galaxy; ultra-deep g- and r- band imaging from the INT/WFC, reaching…

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astro-ph.GAastro-ph.COgr-qc2026年7月17日

Tighter Dark Matter Constraints from the Projected Mass Method: A Neural Network Enhanced Method for Galaxy Groups and Clusters

Yinbo Huang, David Benisty

Measuring the total mass of the Milky Way and nearby galaxy groups is difficult because classical dynamical estimators rely on assumptions about satellite orbital geometry that are rarely satisfied in practice, and because only a handful of satellite galaxies are typically available as kinematic tracers. We present a new framework that corrects the well-known Projected Mass Estimator (PME) using a residual neural network trained on thousands of simulated galaxy groups from the IllustrisTNG cosmo…

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astro-ph.HE2026年7月17日

When will T Coronae Borealis next erupt as a nova? Constraints from recurrence, orbital phase, and accretion-state evolution

Songpeng Pei, Xiaowan Zhang, Renzhi Su, Ziwei Ou, Yongzhi Cai, Qiang Li, Yu Liu, Xiaoqin Ren et al.

T Coronae Borealis (T CrB) is the nearest symbiotic recurrent nova and is now intensively monitored for its next eruption. We combine three constraints on the eruption time: historical recurrence, orbital phase, and recent accretion-state evolution. Conditioning on no eruption by 2026 July 11, the three effective historical intervals give illustrative survival-conditioned probabilities of 30.2\% for the rest of 2026 and 56.9\% within the following year; these are empirical indicators, not physic…

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astro-ph.EPphysics.geo-ph2026年7月17日

Sulfur photochemistry observationally traces mantle redox states of rocky planets

Ioannis Panagiotou, Tim Lichtenberg, Shang-Min Tsai, Harrison Nicholls

Volatile outgassing from planetary interiors controls the composition of rocky exoplanets' secondary atmospheres. However, observations indicate that disequilibrium processes, such as photochemistry and vertical transport, can strongly alter the chemical structure of Hot Jupiters. Which process dominates under different types of rocky planets, and how outgassing and photochemistry jointly determine the atmospheric composition, remain open questions. Sulfur species are promising tracers of interi…

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astro-ph.HE2026年7月17日

Spectral study of the outburst decay of the accreting millisecond X-ray pulsar SRGA J144459.2-604207

Amar Deo Chandra

We study the spectra of the accreting X-ray millisecond pulsar SRGA J144459.2-604207 during the 2024 outburst using the Neutron star Interior Composition Explorer (NICER) and Swift observations. The spectra during the outburst decay, reflares, and quiescent state are explored using the absorbed Comptonized model. We find that the spectra during the quiescent state can also be explained using the absorbed power-law and absorbed blackbody model. The spectral evolution of the source is explored as…

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astro-ph.GAastro-ph.SR2026年7月17日

Cluster characteristics of Galactic open clusters

K. Neumannová, J. Supíková, N. Faltová, P. Mondal, E. Paunzen, T. Ramezani, G. Szász

Star clusters are perfectly suited for studying the formation, evolution, and dynamics of stars and their host galaxies. For this, we need to estimate total masses, radii and shapes of star clusters. These parameters strongly influence their fates in the host galaxies. However, there is no agreement about these characteristics in the literature. The published values widely disagree. We estimated total masses and cluster radii using a very conservative approach: calculating member masses and summ…

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astro-ph.EP2026年7月17日

The majority of hot Jupiters formed beyond the water ice line

Yaxing He, Bertram Bitsch, Adrien Houge, Joe Williams, Masahiro Ogihara

Atmospheric compositions of giant exoplanets can retain information about their formation environments, as volatile species condense at different temperatures in protoplanetary discs. We investigated whether the atmospheric compositions of hot Jupiters can constrain their formation locations. We performed planet formation simulations using the ChemComp code, including pebble drift, pebble and gas accretion, planet migration, stellar abundances, and two additional chemical processes: thermal deco…

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astro-ph.GA2026年7月17日

Berkeley 32: A Metal-poor and Dynamically Evolved Open Cluster with Evidence of Radial Migration

Deniz Cennet Çınar, D. Bisht, Ing-Guey Jiang, W. H. Elsanhoury, K. Belwal, Selçuk Bilir

We present a comprehensive chemo-dynamical analysis of the old, metal-poor open cluster Berkeley 32 based on Gaia DR3 astrometry and Gaia-ESO Survey DR5.1 spectroscopy. Cluster membership is determined using a Gaussian Mixture Model applied to proper-motion components and trigonometric parallaxes. Isochrone fitting yields an age of 4.9 +/- 0.5 Gyr, a heliocentric distance of 3325 pc, and an extinction of A_V = 0.38 +/- 0.12 mag. Spectroscopic member stars exhibit a mean metallicity of [Fe/H] = -…

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astro-ph.HEastro-ph.IMgr-qc2026年7月17日

Swift gives a new BAT-GLIMPSE: Gamma-ray Localization using Imaging and Mosaic techniques for Pointing and Slew Epochs

S. Ronchini, T. Parsotan, J. DeLaunay, J. A. Kennea

The Burst Alert Telescope (BAT) onboard the Neil Gehrels Swift Observatory is capable of localizing gamma-ray transients with arcminute precision, enabling rapid multi-wavelength follow-up. However, onboard triggering is disabled during spacecraft slews, preventing the autonomous detection and localization of transients occurring during these intervals. We present here BAT-GLIMPSE, a fully autonomous, open-source pipeline for the low-latency localization of transient gamma-ray sources in Swift-B…

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