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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.IM

uGMRT Polarization Observations with Walsh Modulation

Salmoli Ghosh, Preeti Kharb, Sandeep Chaudhari, Surajit Mondal

In this report, we discuss the performance of the Walsh phase-switching scheme for Band 4 (550-750 MHz) polarimetric observations with the upgraded GMRT (uGMRT). We have carried out test observations with the Walsh modulation enabled and disabled, using the polarized calibrator 3C138 as the target and unpolarized calibrator 3C147 for amplitude, phase and leakage calibration. The two Walsh datasets (ON & OFF) were processed using identical flagging, calibration, and imaging procedures. The Walsh…

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astro-ph.HEastro-ph.IM

mm-jets in the multi-messenger era

Karri I. I. Koljonen, Thomas D. Russell, Britton Jeter, Lauren Rhodes, Alexandra J. Tetarenko, María Díaz Trigo, Talvikki Hovatta, Pau Bosch-Cabot et al.

Jets and outflows operate across the full cosmic mass scale from young stellar objects (YSOs) and X-ray binaries (XRBs) to active galactic nuclei (AGN), gamma-ray bursts (GRBs), and tidal disruption events (TDEs), shaping many time-domain and multi-messenger transients. Key questions concern on how jets are launched, accelerated and collimated; where and how they dissipate energy and accelerate particles; and how they couple to their environments to set electromagnetic counterpart diversity and…

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astro-ph.IMastro-ph.HE

Understanding cosmic explosions

Karri I. I. Koljonen, Tomek Kamiński, Anna Y. Q. Ho, Thomas Maccarone, Aneurin Evans, María Díaz Trigo, Thomas D. Russell, Dieu D. Nguyen et al.

Millimeter-wavelength observations provide a uniquely sensitive window into the physics of cosmic explosions, from supernovae (SNe) and tidal disruption events (TDEs) to nova eruptions, stellar mergers and electromagnetic counterparts to gravitational wave (GW) sources. Over the past decade, discoveries across the transient sky have revealed that many of the most informative phases of shock interaction, particle acceleration and jet formation unfold at frequencies above the traditional cm-wave d…

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astro-ph.GA

The ALMA-QUARKS Survey. IV. Core Mass Function and Evolutionary Trends in Core Formation Efficiency and Chemistry

Wenyu Jiao, Tie Liu, Dongting Yang, Fengwei Xu, Guido Garay, Patricio Sanhueza, Kee-Tae Kim, Yankun Zhang et al.

The ALMA-QUARKS (Querying Underlying Mechanisms of Massive Star Formation with ALMA-Resolved Gas Kinematics and Structures) survey targets 139 massive protoclusters selected from the ATOMS survey. The targets were observed at 1.3~mm wavelength with an angular resolution of $\sim0.3^{\prime\prime}$, corresponding to $\sim10^3$~au at the sample's median distance of $\sim3.8$~kpc. Using \texttt{getsf}, we identify 3374 dense cores and classify them as starless, protostellar, hot core, or H{\sc ii}…

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astro-ph.SRastro-ph.HE

Beyond Mergers: the Role of Metallicity in Forming a Reservoir of Massive and Detached Binary Black Hole Systems

Siyuan Chen, Monica Gallegos-Garcia

Isolated binary evolution is a key pathway to forming binary black hole (BBH) mergers. However, the observed gravitational-wave population indicates it may not account for all mergers, especially those with high primary black hole mass ($\gtrsim 30 M_{\odot}$). Using the binary population synthesis code \texttt{POSYDON}, we simulate populations of binary systems at eight metallicities from $10^{-4}$ to $2\,Z_\odot$ and classify each BH-forming binary as a merging BBH, a detached BBH, or a system…

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astro-ph.SRastro-ph.EPastro-ph.GA

A Search for Dust in the Outflow of the HH212 Class 0 Protostellar System

Adele L. Plunkett, Per Bjerkeli, Jon P. Ramsey, Daniel Harsono, Hannah Shoemaker

Perhaps the most visually striking phenomenon during star formation is the ejection of material along the direction of the protostar's rotational axis. Observed in the form of molecular outflows and/or atomic jets, these features carry away mass, energy and angular momentum from the system. Given the known dust content of protoplanetary disks, and the energetics of outflows, it has been suggested that it should be possible to lift dust from disks via winds, yet limited observational evidence has…

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astro-ph.IMastro-ph.GA

The dawn of the first galaxies

Livia Vallini, Tanio Diaz Santos, Belen Alcalde Pampliega, Hiddo Algera, Manuel Aravena, Cecilia Bacchini, Tom Bakx, Maruša Bradač et al.

Understanding how the first galaxies assembled their stellar mass at cosmic dawn is a central frontier of modern astrophysics. JWST has now revealed an unexpected population of ultraviolet-bright galaxies at z>10, whose intense emission points towards a rapid stellar mass growth that challenges current models of early galaxy assembly. Yet, the cold gas fueling this growth remains hidden: current ALMA sensitivity restricts routine detection to only the brightest ionized-gas tracers such as [OIII]…

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astro-ph.IMastro-ph.GA

The dawn of the first galaxies

Livia Vallini, Tanio Diaz Santos, Belen Alcalde Pampliega, Hiddo Algera, Manuel Aravena, Cecilia Bacchini, Tom Bakx, Maruša Bradač et al.

Understanding how the first galaxies assembled their stellar mass at cosmic dawn is a central frontier of modern astrophysics. JWST has now revealed an unexpected population of ultraviolet-bright galaxies at z>10, whose intense emission points towards a rapid stellar mass growth that challenges current models of early galaxy assembly. Yet, the cold gas fueling this growth remains hidden: current ALMA sensitivity restricts routine detection to only the brightest ionized-gas tracers such as [OIII]…

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astro-ph.HEastro-ph.COhep-ph

Compact Dark Matter with Globular Cluster Pulsars

Soobeom Chung, Jeff A. Dror

Pulsars are exceptionally stable clocks, and a compact dark-matter object passing near the line of sight to a pulsar delays its pulses through the Shapiro effect. The number of detectable transits is set by the integral over the dark-matter density along the line of sight connecting the Earth and the pulsar. Established pulsars in pulsar timing arrays are typically within one kiloparsec of the Earth and hence sit in a dark-matter density comparable to our local value. In this work, we explore gl…

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astro-ph.GAastro-ph.CO

A model for the ongoing subcluster interaction in Centaurus

Felipe S. Lohmann, Magda Arnaboldi, Michael Hilker, Andreas Burkert, Marilena Spavone, Ortwin Gerhard, Marina Rejkuba, Steffen Mieske et al.

Intracluster globular clusters (GCs) preserve the hierarchical and chemical history of galaxy cluster assembly. The nearby Centaurus cluster is believed to be undergoing an interaction between two subclusters, Cen 30 and Cen 45, which should leave an imprint on its intracluster GCs. We aim to characterise the GC population in Centaurus and constrain its recent assembly history, ultimately constructing an interaction scenario consistent with the observational evidence. Using deep VLT/FORS imaging…

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astro-ph.IMastro-ph.GA

Has JWST Seen Everything? Hunting for "NIRCam-dark" Dusty Star-Forming Galaxies at $z \simeq 6 - 9$ with ALMA2040

Fengwu Sun, Belén Alcalde Pampliega, Hiddo Algera, Manuel Aravena, Tom Bakx, Karina I. Caputi, Pierre Cox, Elisabete da Cunha et al.

JWST/NIRCam has recovered the stellar counterparts of many ALMA-detected, formerly HST-dark galaxies, yet ALMA has started identifying dusty star-forming galaxies (DSFGs) at $z>6$ that remain extremely faint or undetected even with NIRCam. These "NIRCam-dark" DSFGs may trace a missing rapid-growth phase connecting UV-luminous galaxies at $z>10$ to massive quiescent galaxies at $z\gtrsim4$. So far, the small, heterogeneously selected NIRCam-dark sample is insufficient to determine their abundance…

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astro-ph.IMastro-ph.GA

ALMA2040: Understanding the Early Assembly of Galaxies - The Formation of Star-Forming Clumps and their Role in Shaping Galaxy Evolution

Anita Zanella, Andreas L. Faisst, Rodrigo Herrera-Camus, Emily Chien, Beleen Alcalde Pampliega, Manuel Aravena, Cecilia Bacchini, Tom Bakx et al.

Astrophysics seeks to explain how galaxies form and evolve through the interplay of stars, gas, and dust. Giant molecular clouds (GMCs), the main reservoirs and sites of star formation, link the cold interstellar medium to the birth of stars and stellar structures. Their properties reflect galactic disk conditions, and their evolution is shaped by stellar feedback and host-galaxy dynamics. Studying GMCs across cosmic time is therefore key to understanding how gas turns into stars and drives gala…

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astro-ph.GA

An Attenuation Bump at z=9.3: Probing Dust Diversity at Cosmic Dawn

Giulia Rodighiero, Santiago Álvarez-Córdoba, Michele Catone, Borja Pérez-Díaz, Andrea Ferrara, Giorgia Girardi, Lorenzo Napolitano, Paola Santini et al.

We report the identification of a UV attenuation bump in the Black Pearl, a galaxy at a spectroscopic redshift of 9.3335 observed with JWST/NIRSpec as part of the ZENITH and EMBER surveys. This is the highest-redshift UV bump reported to date, probing dust properties only approximately 500 Myr after the Big Bang. The feature is directly detected as a broad depression in the rest-frame UV continuum and is well described by a local Drude profile, with a central wavelength of 2132+/-17 Angstroms, a…

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astro-ph.GAastro-ph.HE

Wandering intermediate-mass black holes and off-nuclear tidal disruption events from early star clusters

Claire E. Williams, Smadar Naoz, Yihao Zhou, Tatsuya Akiba-Lewis, Mark Vogelsberger, Blakesley Burkhart, Naoki Yoshida, Avi Chen et al.

Off-nuclear tidal disruption events (TDEs) reveal evidence for massive black holes outside galactic centers, but the origins of this wandering population remain uncertain. We investigate wandering intermediate-mass black holes (IMBHs) formed through runaway stellar collisions in dense, high-redshift star clusters and predict their TDE signatures across cosmic time. Our semi-analytic model samples clusters associated with low-mass subhalos at $7<z<20$ and uses merger trees from the IllustrisTNG T…

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astro-ph.GA

The Pristine survey XXIX. Data Release 2: Photometric metallicities for 15 millions stars down to $G\sim 20.5$

Zhen Yuan, Anke Ardern-Arentsen, Nicolas F. Martin, Else Starkenburg, Morgan Fouesneau, Piercarlo Bonifacio, Elisabetta Caffau, Vanessa Hill et al.

Tailored narrow-band photometric observations are an efficient way to measure the metallicity of Milky Way stars. The Pristine survey has been mapping the northern sky since 2015 using narrow-band $CaHK$ photometry obtained with the MegaCam imager on the Canada-France-Hawaii Telescope (CFHT). Data Release 1 (DR1) provided a high-precision absolute calibration of the survey observed before October 2022 using \Gaia DR3 XP synthetic photometry, yielding photometric metallicities over $\sim$6,500 de…

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astro-ph.IMastro-ph.EP

Planet forming disk populations and their connection to the environment

Thomas J. Haworth, Giovanni Rosotti, Carlo Manara, Richard Alexander, Rossella Anania, Til Birnstiel, Ryan Boyden, Nicolás Cuello et al.

Existing sub-mm observatories such as ALMA have provided statistics on the planet-forming mass reservoirs within circumstellar disks around stars in stellar clusters out to distances of $\sim$400pc. However, these disks are not where most planets form. Many stars, and hence planets, form in more massive clusters, which are only found at larger distances. Environmental conditions that affect disks - such as UV radiation field, ambient gaseous mass reservoir, and stellar density - change significa…

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astro-ph.GA

HI rotation curves and mass-size relation for 568 galaxies from the Apertif Wide-area Extragalactic Survey

Konstantin Haubner, Federico Lelli, Enrico Di Teodoro, Kelley M. Hess, Francis Duey, Stacy McGaugh, James Schombert, Elizabeth A. K. Adams et al.

The extended HI rotation curves of galaxies are one of the most powerful tools for studying galaxy evolution and for testing different dark matter and modified gravity models. However, their sample sizes have historically been limited to a few hundred galaxies, mostly due to the survey speed of radio interferometers. Here, we present a first data release of HI kinematic models from the Apertif Wide-area Extragalactic Survey (AWES). Starting from 1924 galaxies detected in HI, we constructed 568 r…

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

Probing ordered magnetic fields in galaxies across cosmic time

Jianhang Chen, Melanie Kaasinen, Enrique Lopez-Rodriguez, Wouter Vlemmings, Andrea Lapi, Rosita Paladino, Hannah Stacey, Pierre Cox et al.

Magnetic fields are dynamically important across many astronomical environments, yet their origin, strength, and evolution over cosmic time remain poorly understood. Ordered magnetic fields are ubiquitous in the nearby Universe, as revealed by a range of observational techniques, but evidence for their existence at cosmological distances is scarce. Recent ALMA detections of polarised dust emission indicate that galactic-scale ordered magnetic fields, spanning up to kiloparsec scales, were alread…

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astro-ph.GAastro-ph.HE

How Little Red Dots Turn Blue: Evolution of Kelvin-Helmholtz Contracting Black Hole Envelopes and Observational Diagnostics

Zihao Wang, Kohei Inayoshi

James Webb Space Telescope (JWST) observations have revealed compact, red-colored, broad-line emitters known as little red dots (LRDs), while a bluer counterpart population has been referred to as little blue dots (LBDs). Their physical connection remains unclear: they may represent different evolutionary stages of the same phenomenon, distinct populations, or different phases of the broader evolution of early galaxies and their black holes (BHs). We propose a model in which a rapidly growing BH…

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astro-ph.IMastro-ph.COastro-ph.GA

Tracing small-scale structure formation through cosmic time with strong gravitational lensing: A case for a next-generation sub-millimetre/millimetre interferometer

Hannah R. Stacey, John P. McKean, Mamta Pandey-Pommier, Carla Cornil-Baïotto, Simona Vegetti, Aristeidis Amvrosiadis, Françoise Combes, Giulia Despali et al.

The nature of dark matter and the growth of supermassive black holes (SMBHs) remain major open questions in modern astrophysics. Both leave a key signature in an overlapping, largely unexplored mass range: $<10^7$ M$_{\odot}$ dark haloes and wandering black holes. These may be undetectable directly, but detectable through gravitational perturbation of strongly lensed images, and partly or entirely distinguishable from one another through lensing data alone. We demonstrate through realistic simul…

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astro-ph.GAastro-ph.HE

The Impact of High-Mass Clusters on the Binary Black Hole Merger Rate over Cosmic Time

Aidan Mai, Kyle Kremer, Fulya Kıroğlu

We present a cosmological calculation of the binary black hole merger rate from dense star clusters, using a $\texttt{Cluster Monte Carlo}$ ($\texttt{CMC}$) model grid spanning the full observed parameter space of cluster mass, metallicity, and virial radius. For the first time, we incorporate $N=10^{7}$-particle $\texttt{CMC}$ models into this calculation, including a new solar-metallicity model, extending the $\texttt{CMC Cluster Catalog}$ to the most massive clusters observed in the local Uni…

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astro-ph.COastro-ph.GAhep-phhep-th

Efficient numerical evolution of self-gravitating systems with dark-matter-baryon scattering

Marc Kamionkowski, Vera Gluscevic, Kris Sigurdson

We present a fast algorithm to numerically evolve a spherically symmetric system consisting of dark matter and gas, including dark-matter-baryon scattering. The method augments the spherical N-body code NSphere, which collapses the six-dimensional phase space of a spherical collisionless system to three dimensions, with a one-dimensional Lagrangian treatment of gas. Dark-matter-baryon scattering is implemented as a Monte-Carlo process between the dark-matter numerical particles and the gas shell…

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astro-ph.EPastro-ph.SR

A Misaligned Debris Disk relative to the Host Star CPD-72 2713 from JWST/NIRCam Imaging

Jingwen Zhang, Maxwell A. Millar-Blanchaer, Kellen Lawson, Jarron Leisenring, Brendan P. Bowler, Aarynn L. Carter, Beth Biller, Tim D. Pearce et al.

Observations of debris disks provide a valuable window to investigate the formation and evolution of planetary systems. We present high-contrast JWST/NIRCam observations of CPD-72 2713, a 24 Myr-old star that belongs to the $β$ Pic moving group. We obtained the first scattered-light images of the disk in both F210M and F444W filters, revealing a nearly face-on orientation. Forward modeling yields disk radii of $\rm 55.4^{+3.0}_{-3.2}\,AU$ (F210M) and $\rm 39.1^{+4.6}_ {-2.6}\,AU$ (F444W), both s…

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astro-ph.HEastro-ph.GAphysics.plasm-ph

The impact of nonlinear Landau damping on cosmic ray streaming and the role of external turbulence

Rouven Lemmerz, Mohamad Shalaby, Ellen Zweibel, Christoph Pfrommer, Timon Thomas

Cosmic rays (CRs) streaming faster than the Alfvén speed generate Alfvén waves that scatter them. The saturated wave amplitude is regulated by a damping mechanism. This damping controls the CR scattering rate and drift velocity, and thus the rate at which CRs transfer momentum and energy to the ambient plasma, which sets the strength of CR feedback. In the ionized interstellar medium, nonlinear Landau damping (NLLD) is commonly invoked as the dominant damping mechanism for Alfvén waves. We test…

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astro-ph.GA

CoRGI in MaNGA - II. NGC 5717: cold-gas accretion and disk growth in a BGG

Damir Gasymov, Ivan Yu. Katkov, Eva K. Grebel, Anna Pasquali, Evgenii V. Rubtsov, Katarina Kraljic, Igor V. Chilingarian, Kirill A. Grishin et al.

Large-scale stellar counter-rotation, in which two coplanar stellar components rotate in opposite directions, is usually interpreted as a signature of external gas accretion. Such systems are most often found in relatively sparse environments, where cold gas can be acquired and remain dynamically undisturbed long enough to settle into a disk. It is less clear whether this channel can operate in massive central galaxies, whose group or cluster environments can heat, strip, or perturb cold gas. He…

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astro-ph.IMastro-ph.GA

A Vision for Little Red Dots in the Low-Redshift Universe with ALMA2040

Fengwu Sun, Xiaojing Lin, Miguel Pereira-Santaella, Dieu D. Nguyen

The discovery of Little Red Dots (LRDs) at high redshifts with JWST has revealed a previously unknown phase of black-hole growth. However, their black-hole (BH) masses, BH-to-stellar mass ratios, cold-gas reservoirs, and depletion times remain uncertain. The recent discovery of low-redshift LRDs at $z\simeq0.1 - 0.9$ creates a decisive opportunity to access their low-$J$ CO lines for measuring molecular gas reservoirs, and the nearest systems can in principle be spatially resolved. We use J1025+…

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astro-ph.GAastro-ph.SR

JWST Observations of RR Lyrae in Leo P

Catherine M. Slaughter, Alessandro Savino, Meredith Durbin, Andrew E. Dolphin, Kristen B. W. McQuinn, Max J. B. Newman, Evan D. Skillman, Daniel R. Weisz et al.

We analyze co-spatial HST/ACS and JWST/NIRCam time-series photometric observations of RR Lyrae in the low-metallicity dwarf galaxy Leo P. This study provides a new opportunity to explore the properties of and potential for metal-poor RR Lyrae studies with JWST using well-understood relationships from past HST work. We identify 20 RR Lyrae in the HST imaging and 15 RR Lyrae in the JWST imaging. We determine the periods, amplitudes, and mean magnitudes for each of the RR Lyrae. We fit the Period-W…

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hep-phastro-ph.HEastro-ph.IMphysics.comp-ph

Transient PULSE: Code for the Transient Propagation of UltraLight (pseudo)Scalars to Earth

Jason Arakawa, Charles Cheung, Muhammad Hani Zaheer, Volodymyr Takhistov, Marianna Safronova

We present Transient PULSE, a software package that numerically implements a previously developed source-to-detector framework for transient ultralight bosonic signals from astrophysical bursts. Predicting these signals relies on connecting the source emission spectrum to its evolution during propagation and the resulting observables at a terrestrial detector. The package discretizes a user supplied energy spectrum into momentum modes, propagates them through a specified matter density profile a…

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astro-ph.IM

International Astrophysical Consortium for High-energy Calibration: Summary of the 18th IACHEC Workshop

K. K. Madsen, C. E. Grant, V. Burwitz, H. Earnshaw, K. Forster, M. Guainazzi, V. L. Kashyap, H. L. Marshall et al.

In this report we summarize the activities of the International Astronomical Consortium for High Energy Calibration (IACHEC) from the 18th IACHEC Workshop at Pelham, Germany. Fifty-six scientists directly involved in the calibration of operational and future high-energy missions gathered during four days to discuss the status of the cross-calibration between the current international complement of X-ray observatories, and the possibilities to improve it. This summary consists of reports from the…

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astro-ph.HE

GRB 181201A: Spectropolarimetric Constraints on Prompt Emission and Magnetic Field Structure

Dhruv S. Bal, Nikita S. Khatiya, Philippe Laurent, Diego Götz, Dieter H. Hartmann, Ramandeep Gill

Gamma-ray bursts (GRBs) have served as testbeds for high-energy astrophysical phenomena since their discovery over 50 years ago. GRB detections reveal diverse properties across events, complicating efforts to constrain their emission mechanisms, magnetic fields, jet structures, and compositions. Spectropolarimetry is a powerful tool utilized to disentangle these properties. INTEGRAL/IBIS has previously detected three polarized GRBs 041219A ($65\pm 26$%), 061122 ($>$33%) and 140206A ($>$28%). We…

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