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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.GA

Estimating the local star formation rate density from ASKAP RACS

Sonja Panjkov, O. Ivy Wong., Rachel L. Webster

Understanding the evolution of the cosmic star formation rate density (SFRD) is key to uncovering how the Universe arrived at its present state. This paper presents a novel and efficient method to estimate the local SFRD, which uses supervised machine learning to first identify a population of star-forming galaxies (SFGs). Next, star-formation rates (SFRs) are determined using the 1.4-GHz radio-continuum emission detected by the Australian Square Kilometre Array Pathfinder (ASKAP). Specifically,…

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astro-ph.IM

Closed-loop Atmospheric Dispersion Correction for High-Contrast Imaging with MagAO-X

Katie Twitchell, Sebastiaan Haffert, Jared R. Males, Laird M. Close, Olivier Guyon, Kyle Van Gorkom, Alexander Hedglen, Parker T. Johnson et al.

Incoming starlight is refracted as it enters Earth's atmosphere from the vacuum of space. The wavelength-dependence of atmospheric refraction causes elongation of the broadband PSF of ground-based telescopes, especially in the visible spectrum. The result is degraded image quality alongside reduced coronagraph light-blocking efficiency, both of which limit high-contrast observations. An atmospheric dispersion corrector (ADC) is a dispersive optic used to compensate for this effect. Current metho…

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astro-ph.GA

Scaling Relations of Galactic Outflows Across Cosmic Time: New Insights from Cosmic Noon

Tiffany Liou, Xinfeng Xu, Allison L. Strom, Nathalie A. Korhonen Cuestas, Claude-André Faucher-Giguère, Tim B. Miller, Gwen Rudie, Ryan F. Trainor et al.

Galactic outflows play a significant role in regulating galaxy evolution. Scaling relations between stellar mass ($M_\ast$), star formation (SFR), and outflow properties have been extensively studied at low redshifts ($z $ 50 for H$α$ or [OIII] $\lambda5007$) from Keck/MOSFIRE spectra, we detect warm-ionized outflows by decomposing lines into narrow and broad components. With the joint sample, we explore the redshift evolution of outflow scaling relations. On average, outflows at Cosmic Noon hav…

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astro-ph.IM

windsoCC: reconstructing the wind-driven halo in MagAO-X images using wavefront sensor telemetry

Jay K. Kueny, Jared R. Males, Alycia J. Weinberger, Laird M. Close, Joseph D. Long, Joshua Liberman, Sebastiaan Haffert, Eden McEwen et al.

The wind-driven halo (WDH) is a persistent, low spatial frequency noise artifact that arises due to the servo-lag error inherent to all adaptive optics (AO) instruments. Spatial filtering may be employed to overcome this artifact, however, filtering out the WDH while simultaneously preserving signal from an extended astrophysical object of interest is exceptionally challenging. Additionally, since the WDH changes in intensity and position angle through an observation, data-driven algorithms (e.g…

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astro-ph.IM

Lunar Reflective Interferometry

Peter W. Gorham, T. Joseph W. Lazio, Andrew Romero-Wolf, Patrick S. Allison, Marin M. Anderson, Ali M. Bramson, Roman Burridge, Amy Connolly et al.

We present the method of lunar reflection interferometry (\hbox{LRI}) in which a virtual interferometer can be formed by using a spacecraft-borne antenna in lunar orbit that receives both direct rays and those reflected from the lunar surface. The technique exploits the method of images and is akin to the classic "sea cliff" interferometer, with the Moon's surface, primarily the lunar Maria, replacing the ocean surface. We describe the method in detail, demonstrate that significant portions of t…

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astro-ph.IM

Lunar Reflective Interferometry

Peter W. Gorham, T. Joseph W. Lazio, Andrew Romero-Wolf, Patrick S. Allison, Marin M. Anderson, Ali M. Bramson, Roman Burridge, Amy Connolly et al.

We present the method of lunar reflection interferometry (LRI) in which a virtual interferometer can be formed by using a spacecraft-borne antenna in lunar orbit that receives both direct rays and those reflected from the lunar surface. The technique exploits the method of images and is akin to the classic "sea cliff" interferometer, with the Moon's surface, primarily the lunar Maria, replacing the ocean surface. We describe the method in detail, demonstrate that significant portions of the Moon…

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astro-ph.IMastro-ph.CO

Tabular foundation models for the estimation of probabilistic quasar photometric redshifts in S-PLUS

Raquel R. Valença, Lilianne Nakazono, Rafael Izbicki, Marco Henrique de Almeida Inácio, Bruno Marcondes e Resende, Maycon Jorge Deláqua da Silva, Kiana Coimbra Buin Lins, Natanael M. Cardoso et al.

We assess whether tabular foundation models can be used as off-the-shelf probabilistic photometric-redshift estimators for quasars in the 12-band S-PLUS DR6 survey, where colour-redshift degeneracies produce multi-modal posteriors and spectroscopic training sets are shifted relative to the photometric population. TabPFN 2.5, RealTabPFN 2.5, and TabICL are benchmarked against eight task-specific baselines, including linear conditional Gaussians, FlexZBoost, mixture-density networks, normalising f…

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gr-qcastro-ph.HE

On the nature of oscillating modes of proto-neutron stars

Dimitra Tseneklidou, Alejandro Torres-Forne, Pablo Cerda-Duran, Martin Obergaulinger, Jose Antonio Font

Newborn proto-neutron stars (PNS) are potential targets of gravitational wave asteroseismology, the study of the (inner) structure of stars via their oscillation modes. To prepare for the eventual detection of such modes by current and future gravitational wave observatories, theoretical studies have obtained the possible spectrum of oscillations. However, there has been disagreement when it comes to identifying and classifying specific modes according to the physical mechanism that excites them…

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astro-ph.HE

Astrophysical Constraints on Hadron--Quark Crossover in Hybrid Neutron Stars

Gábor László Kasza, György Wolf

We investigate astrophysical constraints on hybrid neutron-star equations of state constructed by combining an extended linear sigma model description of quark matter with several representative hadronic equations of state through a smooth hadron--quark crossover. Four different hadronic models are examined in order to explore the model dependence of the resulting hybrid equations of state. After imposing stability, causality, perturbative QCD matching, tidal deformability, and maximum-mass cons…

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astro-ph.SR

Astro+ database. I. Description and first results

K. Rübke, A. Marco, I. Negueruela, A. Herrero, S. Simón-Díaz, H. M. Tabernero, L. R. Patrick

The vast amounts of spectroscopic data for massive stars provided by previous and existing instruments on ground-based and space-based telescopes have saturated our capability to process them by human inspection routines. Consequently, there is a pressing need for fully automatic machine-assisted tools to help handle incoming data. To this end, we present the development of a massive star spectroscopic interactive database, Astro+. We aim to provide users with a reliable, versatile, and user-fri…

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astro-ph.SRastro-ph.GA

The Carbon Giant Population Revealed by Gaia DR3

Benjamin R. Roulston, Paul J. Green

Classical carbon stars (atmospheric C/O >1) are asymptotic giant branch (AGB) stars that become carbon-rich through third dredge-up during the thermally pulsing AGB phase. However, carbon stars also occur among red giants and main-sequence stars, where the carbon is thought to originate from binary mass transfer from a former AGB companion. Using the all-sky catalog of G 5^\circ$, we measure a local disk space density of $n_0=11\pm0.5\times10^{-8},\mathrm{pc}^{-3}$ and a scale height of $H_z=257…

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astro-ph.GA

Electron temperature and emission measure of HII regions in the central molecular zone (CMZ) from H40 αrecombination line and continuum emissions by ALMA CMZ Exploration Survey - ACES -

Yoshiaki Sofue, Steven N. Longmore, Daniel Walker, Adam Ginsburg, Jonathan D. Henshaw, John Bally, Ashley T. Barnes, Cara Battersby et al.

Star formation activity in the Central Molecular Zone (CMZ) directly manifests itself as radio continuum free-free emission (Bremsstrahlung) and radio recombination line emission from HII regions surrounding newly formed massive stars. We derive the overall distribution of the HII regions and their fundamental properties: electron temperature ($\Te$) and emission measure ($EM$), and hence electron density in the form of two dimensional distribution maps over the CMZ by analyzing the ACES (ALMA C…

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astro-ph.GA

Electron temperature and emission measure of HII regions in the central molecular zone (CMZ) from H40 αrecombination line and continuum emissions by ALMA CMZ Exploration Survey - ACES -

Yoshiaki Sofue, Steven N. Longmore, Daniel Walker, Adam Ginsburg, Jonathan D. Henshaw, John Bally, Ashley T. Barnes, Cara Battersby et al.

Star formation activity in the Central Molecular Zone (CMZ) directly manifests itself as radio continuum free-free emission (Bremsstrahlung) and radio recombination line emission from HII regions surrounding newly formed massive stars. We derive the overall distribution of the HII regions and their fundamental properties: electron temperature ($\Te$) and emission measure ($EM$), and hence electron density in the form of two dimensional distribution maps over the CMZ by analyzing the ACES (ALMA C…

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astro-ph.IMastro-ph.EP

The final design of GMagAO-X: high-contrast imaging at first-light of the GMT

Jared R. Males, Laird M. Close, Sebastiaan Y. Haffert, Victor Gasho, Adam Fletcher, Joseph Boales, Dhruv Lakhani, Maggie Y. Kautz et al.

GMagAO-X will be the first-light high-contrast imager on the 25 m Giant Magellan Telescope. The driving science case for GMagAO-X is characterization of the atmospheres of nearby rocky exoplanets such as Proxima Centauri b. The revolutionary increase in spatial resolution and sensitivity provided by GMagAO-X will enable detailed study of such planets for the first time. Additional science cases include: reflected light characterization of mature giant planets; measurement of young extrasolar gia…

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astro-ph.SR

Parametric Study of Torus Instability Threshold

Jun Chen, Bernhard Kliem, Tibor Török, Rui Liu

The torus instability of an arched current channel has been suggested to initiate and drive major solar and stellar eruptions. Its threshold, given by the critical decay index of the equilibrium external poloidal field (the so-called strapping field) at the position of the current channel, is insufficiently known. Here, we carry out a parametric numerical study of the threshold, employing the force-free Titov-Démoulin equilibrium of a line-tied partial toroidal current channel and flux rope. Thi…

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astro-ph.SR

Parametric Study of Torus Instability Threshold

Jun Chen, Bernhard Kliem, Tibor Török, Rui Liu

The torus instability of an arched current channel has been suggested to initiate and drive major solar and stellar eruptions. Its threshold, given by the critical decay index of the equilibrium external poloidal field (the so-called strapping field) at the position of the current channel, is insufficiently known. Here, we carry out a parametric numerical study of the threshold, employing the force-free Titov-Démoulin equilibrium of a line-tied partial toroidal current channel and flux rope. Thi…

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astro-ph.IM

Sensor fusion on MagAO-X: real time vibration control using accelerometers

Parker T. Johnson, Jared R. Males, Povilas Palunas, Olivier Guyon, Sebastiaan Haffert, Joseph Long, Vincent Deo, Julien Lozi et al.

Mechanical vibrations are a significant source of residual wavefront error (WFE) in adaptive optics (AO) systems, limiting the performance of high-contrast imaging instruments. We present the design and on-sky deployment of a low-cost, modular accelerometer telemetry system for the MagAO-X extreme AO instrument on the 6.5 m Magellan Clay Telescope, consisting of piezoelectric accelerometers and a Raspberry Pi-based acquisition system that streams synchronized data to the real-time control comput…

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astro-ph.IM

Wavelength Calibration Accuracy Across the STIS CCD: Pipeline Update and User Guidance

Matilde Mingozzi, Robert Jedrzejewski, Matthew Siebert, Daniel Welty, Sean Lockwood, Joleen Carlberg

We investigate the wavelength calibration accuracy of STIS CCD spectra as a function of detector position, focusing on the E1/E2 pseudo-apertures. Comparison between measured lamp line centroids and laboratory wavelengths shows that, while the standard calstis solution is stable at the detector center, significant offsets are present toward the CCD edges and increase with time. We used a test version of calstis in which the wavelength calibration step employs a row-selected cross-correlation, le…

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astro-ph.GA

The Rotation Curve of the Milky Way: State of the Art, the Keplerian Decline Debate, and Implications for Dark Matter

Alessandro Melchiorri, Ruchika

For four decades, the roughly flat rotation curve (RC) of the Milky Way (MW) stood as local evidence for an extended dark matter (DM) halo. \textit{Gaia} DR3 has changed the picture: several analyses now find a velocity decline beyond R \approx 15\kpc, and the most radical interpretation \citep{jiao2023} claims a nearly Keplerian fall-off (\vc \propto R^{-1/2}) that excludes a flat RC at 3σand implies a total dynamical mass of only \sim 2 \times 10^{11}\Msun---three to five times below pre-\text…

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astro-ph.GA

Constructing X-ray Spectral Models of Galaxies: Varying Contributions from X-ray Binary Populations with Host Galaxy Properties

Emerson Gehr, Bret D. Lehmer, Antara R. Basu-Zych, Konstantinos Kovlakas, Vianney Lebouteiller, Erik B. Monson, Izabela Pavel, Chris Richardson et al.

Recent work has shown that the emission from X-ray binary (XRB) populations in galaxies varies with stellar mass ($M_\star$), star formation rate (SFR), and metallicity ($Z$). Such scaling relations are widely used to predict the XRB contributions to galaxy-integrated X-ray luminosities including studies focused on dwarf active galactic nuclei (AGN) and the X-ray radiation field during the epoch of heating in the early ($z \geq 8$) universe. However, as galaxies approach low SFR and low $Z$, the…

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gr-qcastro-ph.HE

A parametrized test of general relativity for inspiralling eccentric binaries in LISA

Pankaj Saini, Sylvain Marsat, Lorenz Zwick, János Takátsy, Johan Samsing

The space-based detector Laser Interferometer Space Antenna (LISA) will observe inspiralling black hole binaries in the mHz band, many of which may retain orbital eccentricity. In contrast to quasicircular binaries, eccentric systems radiate through multiple orbital harmonics, while relativistic periastron precession introduces a secular phase structure in the waveform. We exploit this structure to develop a parametrized test of general relativity (GR) for eccentric bound orbits. We construct a…

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astro-ph.IM

CCD Rotation Rates From Regular Dispersion Solution Monitoring

Matilde Mingozzi, Matthew Siebert

It has been previously studied that the STIS CCD exhibits a slow rotation, evident from changes in spectral traces and flat-field evolution. In this Instrument Science Report, we present an independent spectroscopic analysis of the CCD rotation angle and a comparison with previous studies. We describe the methodology used to derive rotation angles and rates across different gratings and central wavelengths, and report the corresponding median rotation rates over time. The results are broadly con…

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astro-ph.GA

The Extended Mapping Obscuration to Reionization with ALMA (Ex-MORA) Survey: A Molecular Gas Line Search

V. Catán, J. González-López, M. Aravena, A. S. Long, C. M. Casey, D. L. Clements, E. da Cunha, M. Franco et al.

Current investigations of cold gas in the interstellar medium face selection biases, as optical/near-infrared surveys favor massive, low-obscuration galaxies and miss gas-rich passive or inefficient star-forming systems. Overcoming this requires large-volume line surveys selected by molecular gas rather than stellar luminosity. We present a molecular gas census across $0.5 10^{10}\,\text{M}_{\odot}$). Gas fraction ($μ_{\text{gas}}$) increases with redshift for active populations, though high-red…

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astro-ph.COastro-ph.GA

CORN -- Chronometers of Relic Nature I: The first estimate of the expansion rate of the Universe using compact relic galaxies

Krzysztof Lisiecki, Nicola Principi Cavaterra, Agnieszka Pollo, Chiara Spiniello, Laura Hunt, Charlie Rosen, Marek Biesiada, Darko Donevski et al.

Measuring the expansion rate of the Universe is a central challenge in cosmology, particularly due to the persistent statistically significant discrepancy between the measurements of the Hubble constant, H0, obtained using early- and late-time probes, commonly known as the Hubble tension. Independent and robust methods are therefore essential to validate existing measurements and assess potential systematic effects. We employ the cosmic chronometer (CC) approach, which uses the differential age…

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astro-ph.COastro-ph.GA

CORN -- Chronometers of Relic Nature I: The first estimate of the expansion rate of the Universe using compact relic galaxies

Krzysztof Lisiecki, Nicola Principi Cavaterra, Agnieszka Pollo, Chiara Spiniello, Laura Hunt, Charlie Rosen, Marek Biesiada, Darko Donevski et al.

Measuring the expansion rate of the Universe is a central challenge in cosmology. Independent and robust methods are essential to validate existing measurements and assess potential systematic effects. We employ the cosmic chronometer (CC) approach, which uses the differential age evolution of quiescent galaxies to measure the Hubble parameter H(z) without assuming an underlying cosmological model. In contrast to previous CC studies, we restrict our analysis to relics -- ultra compact massive ga…

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astro-ph.IM

The eXtreme Wavefront Control Toolkit: High-Contrast Imaging Instrument Control for Ground and Space-Based Coronagraphs

Jared R. Males, Joseph D. Long, Sebastiaan Y. Haffert, Kyle Van Gorkom, Parker Johnson, Rico Landman, Eden McEwen, Olivier Guyon et al.

We present the eXtreme Wavefront Control Toolkit (XWCTk) instrument control software system developed for the MagAO-X extreme adaptive optics (ExAO) instrument. The XWCTk is built on a foundation of the ImageStreamIO (ISIO) / MILK / CACAO low-latency image processing and high dimensional control tool chain. Instrument control is managed with the Instrument Neutral Distributed Interface (INDI). The application framework provides configuration, logging, and distributed IPC with INDI and low-latenc…

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astro-ph.IM

Freezing the speckles: focal plane wavefront sensing with the spatially-clipped self-coherent camera

Joshua Liberman, Sebastiaan Y. Haffert, Jared R. Males, Aditya Khandelwal, Stephanie Rinaldi, Joseph D. Long, Katie M. Twitchell, Jay K. Kueny et al.

The next generation of Extremely Large Telescopes (ELTs) and the Habitable Worlds Observatory (HWO) require active speckle suppression to directly image exo-Earths. Focal plane wavefront sensing and control allows us to detect and remove time-varying speckles through measurements of the electric field. Wavefront sensing approaches include pairwise probing (PWP) and the self-coherent camera (SCC). However, the PWP technique is time-consuming, requiring at least 4 images and reducing the speed at…

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astro-ph.SRastro-ph.EP

A Pre-Main Sequence Binary Viewed Through its Circumbinary Disk: A New Phase for KH 15D

Catrina M. Hamilton, Adi B. Chacko, George A. Carson, Aidan J. Pidgeon, C. Nicole Foley, Hillel Finder, Kyle Gimmy, Aleezah Ali et al.

The binary T Tauri system, KH 15D, is poised to provide unprecedented detail of gas and ices located between $\sim$3-5 AU of its circumbinary disk over the next few years. We analyze for the first time a complete set of ground-based time series photometry of the KH 15D system for which the 2022 October - 2025 April data have never been presented. By combining the latest $I$-band data with historical measurements, we show that the era of large amplitude photometric variability has ended. We defin…

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

The Carruthers Mission Concept and Performance

W. Craig, T. Immel, L. Waldrop, J. Troeltzsch, E. Taylor, J. McPhate, K. Rider, A. Butterworth et al.

The Carruthers Geocoronal Observatory (Carruthers), formerly GLIDE, is a NASA Heliophysics Science Mission of Opportunity implemented through the Solar Terrestrial Probes (STP) Program and launched as a rideshare in September 2025. Carruthers is the first spaceflight mission edicated to continuous global imaging of Earth's hydrogen exosphere through observations of geocoronal Lyman-$α$ emission at 121.6 nm. The observatory operates at distances of 1.3-1.7 million km in a halo orbit about the Sun…

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