astro-ph papers | Gist.Science

Analysis of Tidal Perturbations Due to Asymmetric Response of LARES 2 and LAGEOS

This study quantitatively analyzes asymmetric tidal perturbations on the LARES 2 and LAGEOS satellites by identifying 83 significant Earth tide constituents and demonstrating that the cumulative effect of the remaining minor constituents is non-negligible, thereby providing essential parameters for high-precision orbital dynamics and fundamental physics tests like the Lense-Thirring effect.

Xizhi Hu, Xiaodong Chen, Jianqiao Xu, Ignazio Ciufolini, Wei-Tou Ni, Antonio PaolozziWed, 11 Ma🔭 astro-ph

On the modeling and mitigation of interference fringes in polarimetric instrumentation

This paper presents an approximate yet agile modeling framework for analyzing and mitigating spectral and spatial interference fringes in polarimetric instruments, specifically focusing on isotropic materials and uniaxial crystals under the assumption of small birefringence, while validating its accuracy against rigorous methods like Berreman calculus through extensive design examples.

Roberto Casini, David M. HarringtonWed, 11 Ma🔭 astro-ph

$\mathcal{R}^2$ -corrected Tachyon Scalar Field Inflation, the ACT Data, and Phantom Transition

This paper demonstrates that an $\mathcal{R}^2$ -corrected tachyonic scalar field inflation model with a rescaled Einstein-Hilbert term can successfully achieve a phantom divide line crossing and remain compatible with ACT data, provided the effective gravitational constant during inflation is stronger than standard Einstein-Hilbert gravity.

S. D. Odintsov, V. K. OikonomouWed, 11 Ma🔭 astro-ph

Perturbative unitarity bounds on field-space curvature in de Sitter spacetime: purity vs scattering amplitude

This paper establishes that perturbative unitarity in de Sitter spacetime, analyzed via momentum-space entanglement and purity in two-scalar models, imposes an upper bound on field-space curvature of the order of the Hubble scale—a constraint arising from the spacetime's thermal nature that complements traditional flat-space bounds.

Qianhang Cai, Tomoya Inada, Masataka Ishikawa, Kanji Nishii, Toshifumi NoumiWed, 11 Ma🔭 astro-ph

The Formulation of Scaling Expansion in an Euler-Poisson Dark-fluid Model

This paper presents a dark fluid model described as a non-viscous, non-relativistic, rotating, and self-gravitating fluid with spherical symmetry and a polytropic equation of state, which is solved using a self-similar time-dependent ansatz to derive new solutions consistent with the Newtonian cosmological framework that can describe the transition from normal matter to dark energy on cosmological scales.

Balázs Endre Szigeti, Imre Ferenc Barna, Gergely Gábor BarnaföldiWed, 11 Ma🔭 astro-ph

Accretion Geometry of Black Hole X-ray Binaries: Insights from X-ray Observations

This short review summarizes X-ray techniques for measuring accretion geometry in black hole X-ray binaries, highlighting findings that accretion disks can extend close to the innermost stable circular orbit in the bright hard state and discussing the connections between disks, coronas, and jets.

Honghui LiuWed, 11 Ma🔭 astro-ph

On the Influence of Pluto on Twotino Dynamics Through Their Mutual 4:3 Mean Motion Resonance

This study demonstrates that Pluto significantly influences the long-term stability of Twotinos by trapping them in a 4:3 mean motion resonance, a finding that necessitates including Pluto in simulations of the trans-Neptunian region rather than excluding it.

S. Ramírez-Vargas, A. Peimbert, M. A. Muñoz-Gutiérrez, A. Perez-VillegasWed, 11 Ma🔭 astro-ph

Discovery of a compact hierarchical triple main-sequence star system while searching for binary stars with compact objects

This paper reports the discovery and characterization of G1010, a compact hierarchical triple main-sequence star system identified through a combination of Gaia data, multi-epoch spectroscopy, and TESS light curve analysis, which initially appeared to host a massive compact object but was confirmed to consist of a primary star and an eclipsing inner binary.

Ataru Tanikawa, Akito Tajitsu, Satoshi Honda, Hiroyuki Maehara, Bun'ei Sato, Kento Masuda, Masashi Omiya, Hideyuki IzumiuraWed, 11 Ma🔭 astro-ph

Reconstructing Gamma Ray Burst Energy Relations with Observational H(z) data in Neural Network Framework

This paper employs Artificial Neural Networks and Bayesian Neural Networks to perform a model-independent calibration of Gamma-Ray Burst luminosity relations using observational Hubble parameter data, successfully resolving the circularity problem and yielding consistent Amati relation slopes that align with previous low-redshift calibrations.

Nilanjana Bagchi Aurpa, Abha Dev Habib, Nisha RaniWed, 11 Ma🔭 astro-ph

Simulation-Based Prediction of Black Hole Spectra: From $10M_\odot $to$ 10^8 M_\odot$

This paper extends a comprehensive post-processing method for GRMHD simulations to black holes ranging from $10M_\odot $to$ 10^8 M_\odot$, demonstrating that standard radiation physics can successfully reproduce observed spectral properties—including state-dependent shapes in stellar-mass systems and soft X-ray excesses in massive black holes—across the entire mass spectrum.

Chris Nagele, Julian H. Krolik, Rongrong Liu, Brooks E. Kinch, Jeremy D. SchnittmanWed, 11 Ma🔭 astro-ph

The Response of Planetary Atmospheres to the Impact of Icy Comets III: Impact Driven Atmospheric Escape

By coupling cometary impact and planetary atmospheric models, this study demonstrates that while global circulation on tidally-locked exoplanets generally enhances hydrogen escape compared to Earth-analogue atmospheres, the location of an icy comet impact significantly modulates escape rates, with day-side impacts driving an order-of-magnitude higher loss than night-side impacts due to differences in vertical transport efficiency.

Felix Sainsbury-Martinez, Greg Cooke, Catherine WalshWed, 11 Ma🔭 astro-ph

Scalar field dark matter and stepped dark radiation in an extended Wess-Zumino dark radiation model

This paper proposes and constrains a novel cosmological model where scalar field dark matter interacts with stepped dark radiation via pure momentum coupling, finding that while it offers marginal improvements over the original Wess-Zumino dark radiation model in alleviating the Hubble and $S_8$ tensions, it does not fully resolve these cosmological discrepancies.

Gang LiuWed, 11 Ma🔭 astro-ph

XSNAP: An X-ray Supernova Analysis Pipeline with Application to the Type II Supernova 2024ggi

This paper introduces XSNAP, a new open-source Python pipeline for standardized X-ray analysis of supernovae, and applies it to multi-epoch observations of SN 2024ggi to derive a steady progenitor mass-loss rate of $(6.2\pm0.2)\times10^{-5}\,M_{\odot}\,\mathrm{yr^{-1}}$ .

Ferdinand, W. V. Jacobson-Galán, M. M. Kasliwal, Erez A. ZimmermanWed, 11 Ma🔭 astro-ph

Stellar halos of bright central galaxies II: Scaling relations, colors and metallicity evolution with redshift

Using the updated FEGA25 semi-analytic model, this study reveals that stellar halos around bright central galaxies act as dynamically and chemically coupled transition regions to the intracluster light, with their scaling relations, colors, and metallicity evolution across cosmic time showing strong agreement with observed colors but suggesting a larger contribution from disrupted dwarf galaxies than currently predicted.

Emanuele Contini, Marilena Spavone, Rossella Ragusa, Enrica Iodice, Sukyoung K YiWed, 11 Ma🔭 astro-ph

The detection of high X-ray polarization from an accretion disc corona source and its modelling via Monte Carlo radiation transfer simulation

This paper reports a significant detection of high X-ray polarization from the neutron star system 2S 0921-630 using IXPE, revealing distinct polarization properties during eclipse versus out-of-eclipse phases and demonstrating that a Monte Carlo simulation of scattering in a thermal-radiative wind can reproduce the observed polarization degree and its weak energy dependence, though it fails to fully account for the marginal energy-dependent changes in polarization angle.

Ryota Tomaru, Chris Done, Hirokazu OdakaWed, 11 Ma🔭 astro-ph

Lyman- $\alpha$ Escape through Anisotropic Media

This paper employs Monte Carlo radiative transfer simulations to demonstrate that Lyman- $\alpha$ photons escaping through anisotropic, porous neutral gas traverse channels of substantial optical depth rather than the lowest-density paths, leading to suppressed central flux and complex spectral features that challenge the use of Ly $\alpha$ as a direct proxy for ionizing photon escape.

Silvia Almada Monter, Max Gronke, Seok-Jun ChangWed, 11 Ma🔭 astro-ph

Numerical effects on the stripping of dark matter and stars in IllustrisTNG galaxy groups and clusters

This study of IllustrisTNG simulations reveals that while dark matter stripping from satellites is largely resolution-independent, stellar mass stripping is strongly resolution-dependent, with higher resolutions delaying disruption and producing more compact satellites that generate more concentrated stellar haloes, potentially explaining the overprediction of stellar halo mass at large radii.

Mark R. Lovell (ICC Durham, Durham Physics, University of Iceland), Annalisa Pillepich (MPIA), Christoph Engler (MPIA), Dylan Nelson (Heidelberg), Rahul Ramesh (Heidelberg), Volker Springel (MPA), Lars Hernquist (ITP Harvard)Wed, 11 Ma🔭 astro-ph

Stochastic modelling of cosmic-ray sources for Galactic diffuse emissions

This paper employs stochastic Monte Carlo simulations to demonstrate that the discreteness of supernova remnant cosmic-ray sources introduces significant, energy-dependent uncertainties in Galactic diffuse gamma-ray and neutrino emission predictions, particularly in time-dependent diffusion scenarios, which may help reconcile theoretical models with high-energy observations from LHAASO and future experiments.

Anton Stall, Philipp MertschWed, 11 Ma🔭 astro-ph

GRB 221009A: Observations with LST-1 of CTAO and Implications for Structured Jets in Long Gamma-Ray Bursts

Using the LST-1 telescope of the Cherenkov Telescope Array, researchers detected a statistically significant excess of very-high-energy gamma rays from GRB 221009A approximately 1.33 days after the burst, a finding that constrains theoretical models of structured jets by disfavoring those predicting flux levels significantly above $10^{-11} $erg cm$ ^{-2} $s$ ^{-1}$ at that epoch.

Taking a Break at Cosmic Noon: Continuum-selected Low-mass Galaxies Require Long Burst Cycles

This study utilizes JWST observations of 43 low-mass galaxies at cosmic noon to demonstrate that their star formation is governed by long-duration burst cycles with significant quiescent phases, challenging the notion that these systems should be classified solely by their instantaneous star formation rates.

Abby Mintz, David J. Setton, Jenny E. Greene, Joel Leja, Bingjie Wang, Emilie Burnham, Katherine A. Suess, Hakim Atek, Rachel Bezanson, Gabriel Brammer, Sam E. Cutler, Pratika Dayal, Robert Feldmann, Lukas J. Furtak, Karl Glazebrook, Gourav Khullar, Vasily Kokorev, Ivo Labbé, Jorryt Matthee, Michael V. Maseda, Tim B. Miller, Ikki Mitsuhashi, Themiya Nanayakkara, Richard Pan, Sedona H. Price, John R. Weaver, Katherine E. Whitaker, Belinda WuWed, 11 Ma🔭 astro-ph

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