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Research Trends

Latest preprints in space engineering and astrophysics.

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

A machine-learning-driven dataset of 144,111 polycyclic aromatic hydrocarbon infrared spectra for interpreting aromatic infrared bands

Xinghong Mai, Zu-Jia Lu, Zhao Wang

The interpretation of interstellar aromatic infrared bands (AIBs) relies on reference spectral libraries, but the chemical space covered by existing databases remains incomplete relative to the vast structural diversity of polycyclic aromatic hydrocarbons (PAHs) expected in the interstellar medium. We present a large-scale, high-throughput PAH infrared (IR) spectral database that complements existing reference libraries by providing significantly more continuous coverage of the PAH chemical spac…

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astro-ph.GA

An Energetic Consistency Test for Feedback-Driven Gas Loss in Milky Way Dwarf Satellites

Sena A. Matsui, Tsutomu T. Takeuchi, Suchetha Cooray, Kiyoaki Christopher Omori

Dwarf spheroidal galaxies (dSphs) contain little detectable cold gas, but the relative roles of stellar feedback, reionization, and environmental effects in their gas loss remain uncertain. We apply an order-of-magnitude energy-budget test to nine Milky Way dwarf satellites using published color--magnitude-diagram star formation histories (SFHs), galaxy-level velocity dispersions, effective radii, and integrated $V$-band luminosities. For each galaxy and halo prescription, we define the energy-e…

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astro-ph.HEastro-ph.IMhep-exhep-ph

Dark Matter Particle Explorer: Ten-Year On-Orbit Performance and Scientific Outcomes

Jian-Hua Guo, Chuan Yue, Yun-Long Zhang, Yi-Zhong Fan, Jin Chang

The Dark Matter Particle Explorer (DAMPE, also known as ``Wukong'') is the first scientific space mission within the framework of the Strategic Pioneer Program on Space Science of the Chinese Academy of Sciences. The main scientific objectives of DAMPE include indirect detection of dark matter, cosmic-ray physics, and high energy gamma-ray astronomy. Thanks to its large geometrical factor and thick imaging calorimeter, DAMPE could effectively detect cosmic-ray electrons (including positrons) and…

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astro-ph.HEastro-ph.IMhep-exhep-ph

Dark Matter Particle Explorer: Ten-Year On-Orbit Performance and Scientific Outcomes

Jian-Hua Guo, Chuan Yue, Yun-Long Zhang, Yi-Zhong Fan, Jin Chang

The Dark Matter Particle Explorer (DAMPE, also known as ``Wukong'') is the first scientific space mission within the framework of the Strategic Pioneer Program on Space Science of the Chinese Academy of Sciences. The main scientific objectives of DAMPE include indirect detection of dark matter, cosmic-ray physics, and high energy gamma-ray astronomy. Thanks to its large geometrical factor and thick imaging calorimeter, DAMPE could effectively detect cosmic-ray electrons (including positrons) and…

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astro-ph.IM

CHARIZARD: A High-throughput Generic Pipeline for Present and Upcoming Interferometers

Arpan Pal, Ruta Kale

Radio interferometers now deliver wide bandwidths and high sensitivity, and with them data volumes that are awkward to reduce by hand and slow to reduce automatically. The limit is not always the algorithms themselves but the way the work is laid out across the computing available. We present CHARIZARD, a pipeline that carries a raw measurement set through flagging, cross-calibration, self-calibration and imaging to full-Stokes images, and which is built around distributing that work. The observ…

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astro-ph.GA

ALMA observations towards M83 reveal N2H+ tracing dense gas

Nanase Harada, Yuri Nishimura, Toshiki Saito, Mario Tafalla, Jin Koda, Doris Arzoumanian, Sophia K. Stuber, Akihiko Hirota et al.

Galactic observations have shown that N2H+ intensities preferentially trace star-forming dense molecular gas compared with HCN or HCO+, which are conventionally used as dense-gas tracers in extragalactic studies. In this study, we aim to verify this trend in the nearby star-forming galaxy M83. Using ALMA, we observed the J=1-0 transitions of N2H+ and HCN, along with the 1-mm and 3-mm continuum, and analyzed the archival CO(1-0) data. The data achieved a spatial resolution of 48 pc in the southwe…

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astro-ph.EP

Orbital Stability of Apsidally Aligned Planetary Systems

Gabriel Teixeira Guimarães, Eiichiro Kokubo

The dynamical stability of compact planetary systems is known to depend strongly on orbital eccentricities, but the physical role of apsidal alignment remains poorly understood. We investigate this problem using direct {\em N}-body simulations by separating planetary eccentricities into a systematic component shared by all planets and a random component that determines the degree of apsidal alignment. We find that these two components play fundamentally different dynamical roles. Random eccentri…

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gr-qcastro-ph.IMphysics.ins-detphysics.opticsquant-ph

Displacement-noise-free gravitational-wave detector using quantum tomography of photon orbital angular momentum states

Haorong Wu, Xilong Fan, Lixiang Chen

Gravitational waves (GWs) induce quantum transitions between photon orbital-angular-momentum (OAM) states with amplitudes $α_{\pm}$. Exploiting this effect, we present a displacement-noise-free detection framework that extracts GW information from the OAM Hilbert space. Parametrized quantum state tomography of the GW-induced OAM sidebands enables a single V-shaped detector to resolve all seven wave parameters: the frequency, propagation direction, two polarization amplitudes, and initial phase o…

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astro-ph.HE

Neutrino production at the extreme vicinity of supermassive black hole in NGC 1068

Zhi-Peng Ma, Kai Wang

The identification of NGC~1068 as an extragalactic high-energy neutrino source raises the question of the physical conditions required for neutrino production. Motivated by the newly updated IceCube data (down to $\sim 0.2 \,\rm TeV$) for NGC 1068, we present a statistical, model-independent inference primarily constrained by the multi-messenger observations. We calculate neutrino production from hadronic channels (including hadronuclear and photomeson processes) and the accompanying cascade gam…

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astro-ph.HE

Neutrino production at the extreme vicinity of supermassive black hole in NGC 1068

Zhi-Peng Ma, Kai Wang

The identification of NGC~1068 as an extragalactic high-energy neutrino source raises the question of the physical conditions required for neutrino production. Motivated by the newly updated IceCube data (down to $\sim 0.2 \,\rm TeV$) for NGC 1068, we present a statistical, model-independent inference primarily constrained by the multi-messenger observations. We calculate neutrino production from hadronic channels (including hadronuclear and photomeson processes) and the accompanying cascade gam…

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astro-ph.SR

Finite-Element Asteroseismology I: Two-Dimensional Adiabatic Oscillations of Rapidly Rotating N=3 Polytropes

Zhao Guo, Adrian J. Barker

We develop a finite-element formulation for linear adiabatic oscillations of axisymmetric uniformly rotating, centrifugally distorted, self-gravitating N=3 polytropes. Equilibrium models are constructed using self-consistent-field iteration and then remeshed on a surface-fitted oblate meridional domain. The quadratic eigenvalue problem describing oscillations for each azimuthal wavenumber $m$ is solved using a conforming two-domain mesh. The density-weighted displacement, $\boldsymbol{u}=ρ^{1/2}…

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astro-ph.HEastro-ph.GA

Detecting and Identifying Supernovae in AGN Accretion Disks

Zhi-Peng Ma, Kai Wang

Stars may become embedded in active galactic nucleus (AGN) accretion disks and eventually explode as supernovae (SNe), whose detection would provide direct evidence for the existence and evolution of stars in AGN disks. We investigate the electromagnetic emission of such disk SNe using an analytic shock dynamics model coupled with a one-zone radiation model. Applying this framework to four progenitor types over a range of AGN black hole masses and Eddington ratios, we find that disk SNe around l…

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physics.ins-detastro-ph.IMhep-ex

Long-Lived Charge Trap Characterization for Rare-Event Searches with Skipper-CCDs

Ansh Desai, Ana M. Botti, Brenda A. Cervantes-Vergara, Rouven Essig, Stephen E. Holland, Ian Lawson, Steffon Luoma, Santiago Perez et al.

Skipper Charge-Coupled Devices (Skipper-CCDs) are detectors with sub-electron resolution, allowing them to play a critical role in rare-event searches. A major challenge in experiments using these detectors is understanding and mitigating low-energy backgrounds which impact the single-electron rate. One potential component of the single-electron rate could arise from single-electron charge traps caused by lattice defects. In this work we use a new in-situ technique for generating uniform charge…

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hep-phastro-ph.COastro-ph.GAhep-ex

Testing the inelastic dark matter interpretation of the LZ event with heavy-element experiments

Peter W. Graham, Juan P. Luengas, Harikrishnan Ramani, Samuel S. Y. Wong

We consider the inelastic dark matter interpretation of the recent 248 keV event observed by LZ and identify different experiments that could test it. Details of the underlying model and the ability of complementary experiments to test it depend significantly on the high-velocity tail of the dark matter distribution. We consider several example velocity distributions motivated by the impact of the Large Magellanic Cloud (LMC) in order to map out the effects of this dependence. For example, we il…

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astro-ph.GA

ACACIAS II: element abundances for 39 stars in the dwarf galaxy Sculptor

Anell Cornejo-Cárdenas, Sven Buder, Melissa K. Ness, J. Trevor Mendel

Element abundances in nearby galaxies provide insights into their chemical enrichment histories and place the Milky Way and its neighbours in a broader cosmological context. These systems can be studied through individual stars, whose resolved spectra enable the construction of a chemical abundance census of the Local Group. We present the second stage of the ACACIAS (extra-galactic ArChAeology with Cannon Inferred Abundances from resolved integral field unit Spectra) program, which aims to buil…

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astro-ph.SR

EPRV Asteroseismology of the K dwarfs GJ 570 A and GJ 783 A with ESPRESSO. Empirical mode-amplitude scaling in tension with 3D convection simulations

T. L. Campante, Y. Zhou, Y. Li, H. Kjeldsen, R. R. Costa, A. W. Neitzel, J. H. C. Martins, A. M. Silva et al.

Solar-like oscillations in K dwarfs have intrinsically low amplitudes, making them challenging to detect in space-based photometry. The advent of Extremely Precise Radial Velocity (EPRV) instrumentation enables Doppler asteroseismology in the mid-K regime, providing a new opportunity to test mode-excitation and damping physics. We investigate the scaling of oscillation amplitudes with stellar parameters and assess whether 3D surface convection simulations reproduce the observed amplitude behavio…

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astro-ph.HE

A model for the image structure and spectral energy distribution of relativistic jets

Dominic W. Pesce, Ramesh Narayan, Yuh Tsunetoe

Upcoming advances in high-frequency VLBI promise to enable spatially resolved studies of astrophysical jets across an increasingly large source population. We present here a Python implementation of the semi-analytic model from Tsunetoe et al. (2025) for self-consistently interpreting the spatial and spectral structure of the synchrotron emission from such jets. The model is based on an axisymmetric force-free jet solution supplemented with a prescription for nonthermal electron heating, synchro…

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astro-ph.GAastro-ph.HE

JWST reveals a highly ionized nebula powered by an ultraluminous X-ray source with a massive black hole in the metal-poor galaxy Holmberg II

F. A. Fogantini, P. Zeidler, L. M. Oskinova, T. Bao, W. -R. Hamann, P. Marchant, D. M. -A. Meyer, D. Pauli et al.

Recent James Webb Space Telescope (JWST) observations have revealed fine-structure lines of ions with ionization potentials ${\gtrsim}50$\,eV, such as [Ne\,{\sc v}] and [O\,{\sc iv}], in nebular spectra of some low-metallicity galaxies, raising questions about the nature of the ionizing sources. Ultraluminous X-ray sources (ULXs) have been considered as potential contributors, but direct evidence linking individual ULXs to highly ionized nebulae is limited. Here we present JWST IFU spectroscopy…

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astro-ph.IMastro-ph.SR

The energetic atmosphere of the Sun

Sven Wedemeyer, Mats Kirkaune, Miroslav Barta, Astrid M. Veronig, Stanislav Gunar, Roman Brajsa, Manuela Temmer, Valery Nakariakov et al.

Understanding the mechanisms that heat the Sun's chromosphere and corona to temperatures far exceeding those of the solar photosphere below remains one of the central challenges in solar physics. Small-scale, rapidly evolving processes - including shocks, turbulence, magnetohydrodynamic waves, reconnection-driven jets, and nano-flares - are thought to contribute significantly to the heating budget. However, direct observational constraints on their spatial, temporal, and spectral signatures rema…

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astro-ph.IM

Optimization of multi-resolution observation strategies for cosmic microwave background experiments

Sara M. Simon, Jacques Delabrouille, Julien Carron, Reijo Keskitalo, Darcy R. Barron, Shamik Ghosh, Katie Dalton

Cosmic microwave background (CMB) observations are increasingly performed by using a combination of both small aperture telescopes (SATs) and large aperture telescopes (LATs) to extract information across a wide variety of angular scales. The observation strategy of the telescopes must balance the restrictions of the observing site, instrument constraints, and a variety of science goals. We present a general framework for simulating the performance of different observation strategies. Using this…

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astro-ph.GAastro-ph.CO

Self Calibrated Galaxy Groups from the DESI DR1 Bright Galaxy Survey

I. Williams, J. Tinker, K. Wang, J. Aguilar, S. Ahlen, F. Beutler, D. Bianchi, D. Brooks et al.

We present a galaxy group catalog built from Data Release 1 of the Dark Energy Spectroscopic Instrument (DESI) Bright Galaxy Survey, using the Self Calibrated Group Finder. The algorithm uses clustering data from the observed sample to calibrate the Group Finder's free parameters, rather than simulations. The catalog contains 2,229,741 galaxies from ~$2680$ deg$^2$ of sky with 3-pass coverage and $r$-band fluxes $\lt 19.5$. The catalog classifies all galaxies in the flux-limited sample as centra…

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astro-ph.IMastro-ph.GA

Unveiling the Baryon Cycle Through Cosmic Time

Manuel Aravena, Leindert A. Boogaard, Jorge González-López, Ryan Keenan, Chiara Circosta, Pierre Cox, Roberto Decarli, Tanio Díaz-Santos et al.

Galaxy evolution is governed by the baryon cycle: gas accreted from the cosmic web and circumgalactic medium condenses into molecular gas, forms stars, and is redistributed by stellar and AGN feedback. Tracing the molecular phase is therefore essential to understanding how galaxies acquire, consume, and eject their baryons. Yet current molecular-gas surveys remain limited by sensitivity, area, cosmic variance, and spectral bandwidth. ALMA2040 would combine a $\sim10\times$ sensitivity improvemen…

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astro-ph.HE

FUGUE: A New GPU-accelerated General Relativistic Magnetohydrodynamics Code with Weak-Field Multipole Self-Gravity and Quasi-Stationary Kerr Black Hole Evolution

Piotr Plonka, Agnieszka Janiuk

We present FUGUE, a new GPU-accelerated code for general relativistic magnetohydrodynamics (GRMHD). The code supports an optional quasi-stationary update of the Kerr black hole mass and spin, as well as weak-field multipole self-gravity computed with a spherical harmonic Poisson solver. The calculations using high-order multipoles in the Poisson solver are expensive, so the self-gravity solver is well suited for GPU acceleration. The code uses shock-capturing methods and a second-order Runge--Ku…

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astro-ph.HEastro-ph.IM

Study of pulse jitter characteristics of PSR J1744-1134: Towards high precision pulsar timing with InPTA

Jibin Jose, Manoneeta Chakraborty, Neelam Dhanda Batra, K Nobleson, Shantanu Desai, Manjari Bagchi, Bhal Chandra Joshi, Keitaro Takahashi et al.

Variations in the shapes of individual pulses introduce a broadband noise component in pulsar times of arrival beyond what is expected from radiometer noise, referred to as the jitter noise. This noise limits the timing accuracy and, consequently, the sensitivity required for the detection of nanohertz gravitational waves using pulsar timing arrays. Accurate characterization of jitter noise, including its amplitude and frequency dependence, is therefore essential for each pulsar. In this work, w…

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astro-ph.IM

Correlated Radio Frequency Interference Monitor for Radio Telescopes

Lindsay Berkhout, Ian Hendricksen, Joshua Montgomery, Arnab Chakraborty, Jean-Francois Cliche, Matt Dobbs, Albert Wai Kit Lau, James Mertens et al.

Radio frequency interference (RFI) is one of the biggest challenges facing current radio astronomy experiments. Telescopes like the Canadian Hydrogen Observatory and Radio transient Detector (CHORD) need to accurately identify RFI to deliver on their science goals. For applications like HI intensity mapping for precision cosmology, long integrations consisting of hundreds to thousands of hours are needed, and thorough RFI flagging is required to avoid contaminating deep datasets. Currently, many…

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astro-ph.IM

Modal estimation of high-order wavefront drifts on coronagraphic testbeds for high-contrast direct imaging of exoplanets

Saikrishna Manojkumar, Susan F. Redmond, Leonid Pogorelyuk, Ajay S. Gill, Laurent Pueyo, Emiel H. Por, Iva Laginja, Raphaël Pourcelot et al.

Long-term wavefront stability will be critical for the upcoming Habitable Worlds Observatory which aims to directly image exo-Earths. Mechanical and thermal instabilities induce slow, high-order wavefront errors which can degrade the contrast and in turn, the scientific yield of the observatory. Dark zone maintenance (DZM) has been proposed as a high-order wavefront sensing and control strategy to maintain contrast despite wavefront error drifts. This approach uses an Extended Kalman Filter (EKF…

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astro-ph.GA

The optical colors of hidden spiral-like features in nine Virgo early--type dwarfs

Mauricio Gracia, Rory Smith, Anna Pasquali, Laura Ferrarese, Patrick Côté, Hyowon Kim, Paula Calderón-Castillo, Kirsi Pohl et al.

Dwarf early-type galaxies (ETGs) are abundant in nearby clusters and provide a key laboratory for studying environmentally driven galaxy transformation. Although dwarf ETGs were once considered structurally simple, deep imaging has revealed embedded spiral-like features (e.g., bars and spiral arms) in some of them, contributing only a small fraction of the total light. Their origin at dwarf scales remains uncertain. As a pilot study, we investigate spiral-like features in nine Virgo dwarf ETGs w…

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astro-ph.IMastro-ph.GA

What fuels the growth of stars and black holes in galaxies through cosmic time? The physics and chemistry of the interstellar medium in distant galaxies

Leindert A. Boogaard, Manuel Aravena, Matus Rybak, Gergő Popping, Pierre Cox, Irene Shivaei, Jorge González-López, Jacqueline Hodge et al.

The interplay between the baryonic matter in galaxies (gas, dust, stars) has a fundamental role in our understanding of galaxy formation and evolution through cosmic time. The (sub)mm regime provides a unique window to measure the physical conditions and chemistry in the cold and dusty gas reservoirs that fuel the formation of new stars and the growth of massive black holes in distant galaxies. Large sub(mm) interferometers have made a revolutionary impact mapping the cold gas and dust in galaxi…

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gr-qcastro-ph.IM

Optimal Strategies for Gravitational-Wave Memory Detection with Noise Marginalization in Pulsar Timing Arrays

Rand Burnette, Xavier Siemens

Current pulsar timing arrays could detect gravitational wave memory, which would provide a unique test of general relativity. In order to optimize our searches for gravitational wave memory in pulsar timing arrays, we integrate the optimal frequentist statistics for GW memory into the \texttt{enterprise} code suite. We additionally test a noise marginalized version of this statistic, and compare it's effectiveness to the simpler maximum posterior method. We perform these tests on simulated pulsa…

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astro-ph.IM

Multi-Method Machine Learning Classification of Astronomical Sources with Rubin Data Previews: a Spectroscopy-Free Approach with DP1 and DP2

Andrés Alejandro Plazas Malagón, Yasna Ordenes-Briceño, Dan S. Taranu, Alex Broughton, Yumi Choi, Jeffrey L. Carlin, Sophie Reed, Karla Peña Ramírez et al.

We present a multi-method machine-learning study for the binary photometric classification of point-like and extended sources in the Rubin Observatory Data Preview 1 (DP1) and Data Preview 2 (DP2). The workflow runs on the Rubin Science Platform using DP1 and DP2 ugrizy photometry, the DP1 ancillary photometric-redshift catalog, and the Monster astrometric and photometric reference catalog, without relying on external spectroscopy. Six methods (SVM, Random Forest, XGBoost, k-Nearest Neighbors, a…

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