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Research Trends

Latest preprints in space engineering and astrophysics.

cs.CVastro-ph.SR

Super-Resolution of Solar Magnetograms via Adaptive Stratified Ensemble Learning with Uncertainty Estimation

Sina Norouzi Kandalan, Haodi Jiang, Jason T. L. Wang, Qin Li

Single-image super-resolution of Sun's photospheric magnetograms enables consistent analysis across heterogeneous space-based instruments and supports long-term studies of solar magnetic field evolution. We address the super-resolution task from SOHO/MDI (low-resolution) to SDO/HMI (high-resolution) line-of-sight (LOS) magnetograms using a modified RRDBNet architecture initialized by ESRGAN pretrained weights. Through systematic per-image diagnostic analysis, we identify image complexity as the…

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astro-ph.GA

Search for High-Ionization Nebular Emission (SHINE). I. A Systematically Selected [Ne V] Sample at z > 3 with JWST/NIRSpec PRISM

Shobita Satyapal, Sara Doan, Daniel Schaerer, Rui Marques-Chaves, Anurag Sawarkar, William Matzko, Camilo Vazquez, C. Daoutis et al.

We conduct the first systematic Search for High-Ionization Nebular Emission (SHINE) using [Ne V]$\lambda3426$ in JWST/NIRSpec PRISM spectroscopy at $z>3$. From more than 9,000 galaxies, we identify 25 [Ne V] emitters spanning $z=3.059$-$9.444$ and $\log_{10}(L_{\rm [Ne\,V]}/erg\,s^{-1})=40.70$-$42.86$. Their [Ne V] luminosities overlap with those of local [Ne V]-selected active galactic nuclei (AGNs) and exceed those of local metal-poor [Ne V] emitters, although such low-luminosity systems would…

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astro-ph.HE

EP260119a: A High-Redshift Gamma-Ray Quiet Fast X-ray Transient Probing a Potentially Hidden Population of Relativistic Explosions

Camila Angulo-Valdez, Asuka Kuwata, Edilberto Aguilar-Ruiz, Rosa L. Becerra, Ramandeep Gill, Miguel Angel Aloy, Antonio de Ugarte Postigo, Alan M. Watson et al.

Gamma-ray quiet fast X-ray transients (FXTs) provide a new approach for studying relativistic explosions that evade traditional gamma-ray triggers. In this work, we present multi-wavelength observations and analysis of EP260119a, a high-$z$ FXT detected by Einstein Probe/WXT and followed up with COLIBRÍ, the Liverpool Telescope, and other facilities. Spectroscopy yields a redshift of $z = 5.47$, making EP260119a the most distant FXT detected by Einstein Probe to date. Despite its luminous X-ray…

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astro-ph.GAastro-ph.SR

Sequential Star-Formation and the Near-Infrared Stellar Populations within N159

Nolan Habel, E. Sabbi, Peter Zeidler, Tuila Ziliotto, Laurie Chu Margaret Meixner, Guido De Marchi, O. C. Jones, Alec S. Hirschauer et al.

We present the first results from a JWST/NIRCam study of the star-forming region N159, one of the richest H II complexes in the Large Magellanic Cloud. This region stretches over $\sim$130 pc, and exemplifies large-scale sequential star formation. We present photometric results of $>$300,000 point sources combining data from ten near-infrared JWST filters spanning 1-4.7 microns. We detect sources as faint as $\sim$27 magnitudes at F115W, corresponding to stellar masses reaching below $\sim$0.1 $…

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astro-ph.GA

A High Resolution View of Three Massive Young Stellar Objects in the Magellanic Clouds

Yu Cheng, Kei I. Tanaka, Takashi Shimonishi, Yichen Zhang, Suinan Zhang, Kenji Furuya, Asako Sato

The Magellanic Clouds provide an excellent laboratory to study massive star formation beyond typical Galactic environments. Using ALMA band 7 long-baseline observations, we present the highest resolution (approximately 0.03", $1500{\rm\:au}$) view to date of three massive young stellar objects (MYSOs) in the Magellanic Clouds, i.e., Lh03 and Lh09 in the LMC, and S07 in the SMC. The 0.87 mm continuum, with a sensitivity of $\sim30\:μ$Jy beam$^{-1}$, reveals varying levels of fragmentation, from a…

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astro-ph.GAastro-ph.SR

New Optical and Mid-Infrared RR Lyrae Period-Luminosity-Metallicity Relations for Precision Distances and Metallicity Distributions in the Magellanic Clouds

Clara E. Martínez-Vázquez, Joseph P. Mullen, Massimo Marengo, Giuseppe Bono, Vittorio F. Braga, Santi Cassisi, Brian Chaboyer, Massimo Dall'Ora et al.

RR Lyrae (RRL) stars, thanks to the existence of their period-luminosity relations, have been widely used as primary standard candles within the Milky Way and the Local Group of galaxies. We present in this work the latest empirical RRL period-luminosity-metallicity (PLZ) and period-Wesenheit-metallicity (PWZ) relations combining optical ($V, I$) and mid-infrared data ($W1$) using OGLE and WISE photometry, anchored to Gaia DR3 parallaxes. We calibrate these relations with the largest, most compl…

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astro-ph.GA

The galactic HI-to-halo mass relation from isolated galaxies to cosmological hydrodynamic simulations

Marie Korsaga, Jonathan Freundlich, Benoit Famaey, Lourdes Verdes-Montenegro, Amidou Sorgho, Federico Baraggioni, Andrea V. Maccio, Katarina Kraljic et al.

The relation between HI and dark matter (DM) halo masses provides key insights into gas accretion and the regulation of galaxy formation. In a previous study based on SPARC and LITTLE THINGS samples, we showed that the ratio between HI mass and DM halo mass remains approximately constant with stellar mass for nearby disc galaxies ($\log(M_{HI}/M_{200})=-1.90$ with a $1σ$ scatter of 0.37 dex). In this work, we extend that analysis by incorporating galaxies from the Analysis of the interstellar Me…

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physics.space-phphysics.ao-ph

The Localized 12-hour Wave Over Alaska: Leveraging Meridional Wind Measurements From the Sodium Lidar

Sophie R. Phillips, Katrina Bossert, Komal Kumari, Erich Becker, Richard L. Collins, Nicholas Pedatella

The 12-h wave in meridional winds in the mesosphere and lower thermosphere (MLT) during the solar minimum 2018-2019 Arctic winter is investigated using sodium lidar observations at Poker Flat Research Range (PFRR), Chatanika, Alaska (64N,147W). Nightly 12-h wave amplitudes increased significantly during December-January, with amplitudes exceeding 130 m/s above 97 km on several days. This was more than double the 12-h wave amplitudes observed outside this time period. Meteor radar winds over Chat…

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astro-ph.GA

CECILIA: Multi-line Constraints on Excess Nebular Emission from Low-Ionization Gas at Cosmic Noon

Caroline von Raesfeld, Allison L. Strom, Audrey Clarendon, Noah S. J. Rogers, Yijia Li, Nathalie A. Korhonen Cuestas, Gwen C. Rudie, Ryan F. Trainor et al.

Spectroscopy from JWST has offered unique insights into elemental abundance patterns at Cosmic Noon (z~2-3), most notably a growing census of sub-solar S/O. These new measurements, coupled with new observations of [O I]λ6302 at z>1, motivate an updated study of neutral and low-ionization emission within Cosmic Noon galaxies. In this letter, we present a new analysis of [O I]λ6302 and [S II]λλ6718,33 in 19 galaxies observed using ultra-deep JWST/NIRSpec spectroscopy as part of the CECILIA survey.…

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astro-ph.HEastro-ph.GA

Disk truncation triggers relativistic jet launching of a highly accreting supermassive black hole

Hirofumi Noda, Kazuhiro Hada, Hiroto Maruyama, Taishu Kayanoki, Kenji Toma, Taiki Kawamuro, Yoshiyuki Inoue, Tomohisa Kawashima et al.

Relativistic jets are among the most energetic phenomena in the Universe and influence galaxy evolution through energetic feedback, yet the physical connection between accretion flows and jet launching remains unresolved. Jet production is widely attributed to the Blandford-Znajek mechanism, which extracts black hole rotational energy via large-scale magnetic fields sustained by an accretion flow. Although this mechanism is observationally well supported for hot, geometrically-thick accretion fl…

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physics.ed-phastro-ph.IM

A Simple Miniaturized Stellar Interferometer: Measuring the Angular Diameter of Venus with a Masked Telescope

Eric J. Friedman, Michelle Goman

We describe a simple, visually compelling demonstration/laboratory of astronomical interferometry using a standard planetary telescope and a thin piece of opaque plastic punched with two small holes. By observing the disappearance of interference fringes as the hole spacing is increased, students can directly estimate the angular diameter of Venus. The demonstration is a tabletop analogue of the landmark 1921 Michelson-Pease measurement of Betelgeuse and scales naturally from that measurement: w…

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astro-ph.HEastro-ph.GA

In-Situ Star Formation in a Thick Disk: A Model for Metal Enrichment of Mrk 573

Hannalore J. Gerling-Dunsmore, Mitchell C. Begelman, Jared A. Goldberg, Taeho Ryu, Dominika Ł. Król

Recent observations of the nearby Seyfert galaxy Mrk 573 found that the galactic nucleus and bicone regions surrounding the jet are significantly metal-enriched. In this paper, we develop a simple model for the observed metal enrichment, assuming a population of stars in the $10 - 30 \, M_{\odot}$ range formed in-situ in the accretion disk. We assume the stars form according to a Salpeter initial mass function and generate the typical metal yields expected of field stars of the same mass. We fin…

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

A Multiband Catalog of Infrared-Excess Sources in the Vela-Carina Region: VVVX, DECaPS, and GLIMPSE

R. M. Torres, R. K. Saito, V. Fermiano, P. Esteves, B. W. Borges, D. Quispe, D. Minniti

Multiwavelength surveys of the Galactic midplane enable the identification of infrared-excess sources, signatures of circumstellar material, though high extinction and crowding hinder detection. We construct a homogeneous catalog of infrared-excess candidates in a $\sim$7.0 deg$^2$ field of the Vela-Carina region, characterizing their excess emission via spectral energy distribution (SED) analysis. We combine optical photometry from DECaPS, near-infrared photometry from VVVX, and mid-infrared ph…

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astro-ph.IMastro-ph.EPastro-ph.GA

Laboratory Evidence that Methanol-Rich Ice Mantles Lower Methyl Formate Binding Energies

Rachel E. Gross, Jeroen Terwisscha van Scheltinga, L. Ilsedore Cleeves, Catherine A. Dukes, Robin T. Garrod, Alexia Simon, Shane Sawyer, Adam Woodson et al.

Complex organic molecules are widely detected in star-forming regions and are important precursors to prebiotic species. Because these molecules are thought to form primarily within icy grain mantles, their desorption is assumed to be regulated by the sublimation of the surrounding H$_2$O ice matrix. However, observations increasingly reveal gas-phase abundances of methyl formate (MF) at temperatures well below the sublimation temperature of water ice (T ~ 100K), challenging this view. To invest…

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astro-ph.SRastro-ph.HE

Light-curve analysis of the classical nova YZ Ret: revisit with fully self-consistent nova outburst models

Izumi Hachisu, Mariko Kato

YZ Ret is a well observed nova from the first detection of an X-ray flash phase in classical novae until the end of a supersoft X-ray source phase. We have reanalyzed multiwavelength light curves of YZ Ret over the total duration of the outburst. Our fully self-consistent nova outburst model, a 1.25 $M_\odot$ white dwarf (WD) and a mass accretion rate of $1\times 10^{-9} ~M_\odot$ yr$^{-1}$ on to the WD, reasonably reproduced $V$/$g$ light curves as well as the very early X-ray flash and late su…

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astro-ph.GAastro-ph.IM

From starlight to dark matter: a stochastic interpolation approach to map dark matter from stellar density

Xiaowei Ou, Lina Necib, Carolina Cuesta-Lazaro, Paul Torrey, Niusha Ahvazi, Alyson M. Brooks, Berthy T. Feng, Alex M. Garcia et al.

The dark matter halo profile in galaxies holds key information about the nature of dark matter and galaxy formation. Constraining the dark matter profile of galaxies beyond the Milky Way traditionally requires expensive spectroscopic observations for kinematic information. In this paper, we explore a conditional generative model framework to map the dark matter profile of Milky Way-mass galaxies from stellar density profiles, more easily obtainable through large photometric imaging surveys. As a…

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astro-ph.EP

Revisiting planetesimal formation from mm-sized grains in pressure bumps

Tabassum S Tanvir, Jacob B Simon, Daniel Carrera, Jeonghoon Lim

We present evidence that the streaming instability (SI) can form planetesimals from millimeter grains inside axisymmetric pressure bumps, provided the bump is not too strongly reinforced. We conducted three-dimensional local shearing-box simulations of millimeter grains in a Gaussian pressure bump of amplitude $A = 0.6$, at a resolution of $160/H$. We varied only the Newtonian reinforcement timescale $t_{\rm reinf}$, the timescale on which the imposed bump is restored against particle back-react…

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astro-ph.EPastro-ph.SR

M Dwarf Singles and Multis Have Dissimilar Metallicities Indicating Different Origins

Aida Behmard, Sheila Sagear, Yuxi, Lu, Romy Rodríguez Martínez, Adrian M. Price-Whelan, Soichiro Hattori

It is unclear if host star metallicities differ between systems with one detected transiting planet ("singles") or multiple detected transiting planets ("multis") around FGK dwarfs. Here, we find strong evidence that they do for M dwarfs. We use a homogeneous sample of FGK and M dwarf chemical abundances to demonstrate that M dwarf multis are significantly more metal-poor than singles ($p$ = 0.00079), even when we only consider small (<4 $R_{\oplus}$) planets ($p$ = 0.0013). This result emerges…

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astro-ph.GAastro-ph.CO

The lifetimes and properties of Little Red Dots in the AMBRA simulation

Patrick LaChance, Yihao Zhou, Aklant Kumar Bhowmick, Rupert A. C. Croft, Tiziana Di Matteo, Laura Blecha, Fabio Pacucci, Paul Torrey et al.

We identify and analyze the little red dots (LRDs) in the AMBRA cosmological hydrodynamic simulation, by producing mock observations of the galaxies and active galactic nuclei (AGN) between redshifts 5 and 8. We produce these mock observations with both a standard AGN emission model, and a ``gas-enshrouded'' model, and find that the presence of a gas-enshrouded AGN is instrumental to the reproduction of dim LRDs (F444W magnitude $>$ 26.0). We find a steeper decrease in LRD density between $z=5$…

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astro-ph.GAastro-ph.SR

N/O-enhanced chemical enrichment by massive stars: the interplay of optically-thick winds and rotation

Boyuan Liu, Michela Mapelli, Lumen Boco, Xihan Ji

Recent JWST observations have revealed a sample of high-$z$ galaxies with highly-enhanced N/O abundance ratios, $\log\rm (N/O)\gtrsim -1.1$. Strong optically-thick winds of rotating massive stars going through the Wolf-Rayet (WR) phase provide a viable explanation for such N/O enhancements, supported by the direct spectroscopic WR signatures discovered in a few galaxies. Such strong winds are also needed to reproduce the single WR stars in the Small Magellanic Cloud (SMC). Here, we compute the m…

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astro-ph.GAastro-ph.CO

The birth and fate of stellar clumps in super-early galaxies

B. Das, A. Ferrara, A. Pallottini, E. Ntormousi, M. Kohandel

(Abridged) JWST has revealed extremely compact stellar clumps in galaxies at z>6, but their formation mechanism and subsequent evolution remain uncertain. We investigate whether such systems can form in-situ through the fragmentation of an early galactic disk and how stellar feedback regulates their properties. We perform a suite of radiation-hydrodynamical simulations of an isolated galaxy ("Ninfea_blu"), with $\rm M_{vir}=1.5\times10^{10} M_\odot$, evolved for 100 Myr from z=16 to 12.5 with a…

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astro-ph.GA

Cavity-driven Gas Transport in Cool-Core Clusters: Implications for Multiphase Gas Cooling

Prathamesh Tamhane, Brian McNamara, Paul Nulsen

We present a study of gas uplift by cavities and its role in promoting the formation of molecular gas in cool-core galaxy clusters. Using a sample of 24 clusters, we quantify the parameter space of gas uplift, including lifting masses, velocities, radii, and cooling times, and compare the displaced hot gas to observed molecular gas masses. Almost all clusters contain sufficient low-entropy gas within the central $\sim$10 kpc to account for the observed molecular gas. The molecular gas mass scale…

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astro-ph.IMastro-ph.EP

South Pole-Aitken basin sample Return and eXploration (SPARX) Science Definition Team Report

Lauren M. Jozwiak, James T. Keane, Robert Citron, Natalie Curran, Steve Elardo, Caleb Fassett, Abigail Fraeman, Saira Hamid et al.

Sample return from South Pole-Aitken Basin (SPA) on the Moon has been recognized as the highest priority lunar science mission for well over two decades, appearing as a recommended New Frontiers class mission in the two previous Planetary Science Decadal Survey documents (2003-2012 New Frontiers, 2013-2022 Visions and Voyages), and as a prioritized mission for the Lunar Discovery and Exploration Program (LDEP) in the 2023-2032 Origins, Worlds, and Life Decadal Survey. The South Pole-Aitken basin…

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astro-ph.IMastro-ph.CO

The Simons Observatory: Commissioning of the Mid-Frequency Small Aperture Telescopes

Kathleen Harrington, Remington Gerras, Nicholas Galitzki, Samuel Day-Weiss, Yoshinori Sueno, Thomas Alford, Michael J. Randall, Kyohei Yamada et al.

The Simons Observatory (SO) is a cosmic microwave background (CMB) survey experiment observing from an altitude of 5,200 m in the Atacama Desert in Chile. The SO Small Aperture Telescopes (SATs) will cover six spectral bands between 30 and 280 GHz primarily to search for evidence of primordial gravitational waves in the large angular scale $B$-modes of the CMB polarization. The first two Mid-Frequency (MF) SATs, operating in the 90 and 150 GHz frequency bands, began commissioning observations in…

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astro-ph.HEastro-ph.SR

SN2025aico: An Interesting Case Of $^{56}$Ni Mixing, Ejecta Asymmetries, and Dust Formation in a Type IIb Supernova

Grace Davis, Kyle Medler, Chris Ashall, Willem B. Hoogendam, Cameron Pfeffer, David O. Jones, Shunsaku Horiuchi, Tyco Mera et al.

Stripped-envelope supernovae provide a window into how massive stars lose their layers, mix radioactive material, produce dust, and explode asymmetrically. We present optical, near-infrared (NIR), and mid-infrared (MIR) observations of SN~2025aico, a Type~IIb supernova in LEDA~35384. Our spectroscopic sequence, spanning $+1$ to $+167$ d after explosion, follows its evolution from a photospheric phase exhibiting both hydrogen and helium features to prominent helium emission and, ultimately, nebul…

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astro-ph.GA

Radio Quasars in the Cosmic Dawn: A Spectroscopic Sample from the DESI Survey

Anniek J. Gloudemans, Jinyi Yang, David M. Alexander, Arjun Dey, Xiaohui Fan, Victoria A. Fawcett, Martin J. Hardcastle, Stephanie Juneau et al.

We present the largest statistical spectroscopic sample of radio quasars at 4.7 10$). With radio luminosities of $\sim10^{25-28}$ W/Hz, the radio emission in all 83 quasars is expected to be jet-dominated rather than powered by star formation. Analysis of their rest-frame ultra-violet (UV) spectra reveals broadly similar composite spectral properties and CIV velocity shifts compared to radio non-detected quasars. The radio-detected and radio-loud quasars exhibit slightly smaller Ly$α$ and CIV eq…

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astro-ph.EP

Simulated Effects of Radioactive Elements on Magnetic Evolution and Atmospheric Mass Loss of Earth-like Planets

Nathaniel Tanglin, Juliette Becker

Thousands of exoplanets have been discovered in recent decades, yet Earth remains the only known world with life. To assess the potential habitability of other planets, we must identify the importance of various physical conditions that may contribute to sustaining life. One such factor is the presence of a planetary magnetic field. A planet's magnetic field can protect its atmosphere from photoevaporation, and its long-term strength depends on interior heat flow driven by radiogenic heating fro…

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astro-ph.HEastro-ph.CO

Waiting in the wings: extended emission GRBs from high latitude emission and jet expansion

Isabelle Worssam, Benjamin P. Gompertz, Hendrik J. van Eerten

The process powering extended emission (EE) Gamma Ray-Bursts (GRBs) from compact object mergers is a debated problem due to their observed prompt emission timescales of 10 to 100s, far in excess of the expected accretion timescales following a binary neutron star (BNS) merger. Here, we present an analytical thin shell structured jet model designed to alleviate this tension. We show that a changing jet structure in which early emission is produced by a high Lorentz factor narrow, structured jet a…

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hep-phastro-ph.HE

Supernova Gamma-Ray Echo as an Astrophysical Near Detector for Galactic Neutrino Propagation

Garv Chauhan, Yago Porto

Core-collapse supernova neutrinos offer a unique probe of physics beyond the Standard Model over Galactic baselines. Yet even a high-statistics nearby burst may be limited by source uncertainties, especially for propagation effects that average over energy and appear only as an overall flux suppression. Inspired by near--far comparisons in terrestrial oscillation experiments, we show that next-generation MeV observations of the supernova gamma-ray echo---the delayed 511 keV signal induced by the…

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astro-ph.IM

Interference Meets Inference: Bayesian Time-Series Modeling of Radio-Frequency Interference

Jade M. Ducharme, Andrei Li, Michael J. Wilensky, Adrian Liu

Radio-frequency interference (RFI) remains a major challenge for modern radio astronomy experiments. In this work, we cast RFI detection as a one-dimensional time-series anomaly-detection problem and develop a probabilistic mixture-model framework for separating a smoothly varying astronomical background from anomalous contamination. The model jointly describes the clean and contaminated components and assigns each time sample a posterior probability of belonging to the RFI state, rather than re…

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