Clay weekly context brief for the Astro category (ISO week 2026-W31).

Clay tracks publications from the Astro feed list. Below are recent items from this category, each with its source and a short description of what the publication covers when one is available in the source feed.

Recent publications:
1. Radio Core Size of Low-luminosity Active Galactic Nuclei under the MAD-jet model
   Source: astro-ph.GA (Astrophysics of Galaxies)
   Link: https://arxiv.org/abs/2607.21966
   After decades of efforts, there are now fruitful high-resolution radio observations of low-luminosity active galactic nuclei (LLAGNs), and the observed frequency has extended from $\sim$10 GHz up to $\sim$200 GHz.
2. Dynamical analysis of the 5:1 mean-motion resonance of the HD 202206 system
   Source: astro-ph.EP (Earth and Planetary Astrophysics)
   Link: https://arxiv.org/abs/2607.04396
   The HD 202206 system, which features two substellar companions with a 5:1 period ratio around a solar-type star, offers a rare opportunity to study high-order mean-motion resonances and provides new insights into the formation and evolution of substellar companions in extrasolar planetary systems.
3. Flavomons in Matter Gradients: Ray Tracing and Amplitude Evolution
   Source: astro-ph.CO (Cosmology and Nongalactic Astrophysics)
   Link: https://arxiv.org/abs/2604.18689
   Flavor instabilities develop in neutrino plasmas through the emission of flavomons, the quanta of flavor waves.
4. The Distinctive Evolution and Spectral Energy Distribution of Binary Massive Black Hole Accretion
   Source: astro-ph.GA (Astrophysics of Galaxies)
   Link: https://arxiv.org/abs/2607.21956
   Binary (super-)massive black holes (BHs) are expected to reside in the center of some galaxies.
5. Optical design of VIPER: a high-resolution multimode fiber-fed VIPA spectrograph for characterizing exoplanet atmospheric escape
   Source: astro-ph.EP (Earth and Planetary Astrophysics)
   Link: https://arxiv.org/abs/2607.22454
   We present the optical design of VIPER: a high-resolution, multimode fiber-fed, narrowband, cross-dispersed, seeing-limited spectrograph based on a Virtually Imaged Phased Array (VIPA), a spectral disperser that provides higher dispersion and a more compact form factor than conventional diffraction gratings.
6. Black Hole Mergers as the Fastest Photon Ring Scramblers
   Source: astro-ph.CO (Cosmology and Nongalactic Astrophysics)
   Link: https://arxiv.org/abs/2603.08643
   Black holes are the most efficient scramblers in nature.
7. A GRMHD-Calibrated Semi-Analytical Model for Hot Sub-Keplerian Accretion Flows in Kerr Spacetime
   Source: astro-ph.GA (Astrophysics of Galaxies)
   Link: https://arxiv.org/abs/2607.21852
   We develop a simple, semi-analytical, kinematic model for hot, thick accretion flows, constructed by interpolating between Keplerian and free-fall geodesic solutions in the Kerr metric.
8. Spin-spin coupling in stellar binaries
   Source: astro-ph.EP (Earth and Planetary Astrophysics)
   Link: https://arxiv.org/abs/2607.22423
   Spin-orbit misalignment is increasingly observed in binary stars, but its origin remains uncertain.
9. Revisiting PBH accretion, evaporation and their cosmological consequences
   Source: astro-ph.CO (Cosmology and Nongalactic Astrophysics)
   Link: https://arxiv.org/abs/2512.07291
   Primordial black holes (PBHs) provide a unique probe of the early Universe.
10. Echoes of Star Stories: Integrating Indigenous narratives into modern stellar astrophysics
   Source: astro-ph.GA (Astrophysics of Galaxies)
   Link: https://arxiv.org/abs/2607.21679
   Indigenous narratives have long preserved observations of celestial phenomena, offering insights that resonate with modern astrophysical research.
11. Rate of caustic crossing microlensing events in stellar binary lenses with significant orbital motion
   Source: astro-ph.EP (Earth and Planetary Astrophysics)
   Link: https://arxiv.org/abs/2607.21845
   Binary lens microlensing events in which the source crosses a caustic produce sharp, distinctive magnification peaks and can therefore be readily identified.
12. A comprehensive separation of dark matter and baryonic mass components in galaxy clusters I: Mass constraints from Abell S1063
   Source: astro-ph.CO (Cosmology and Nongalactic Astrophysics)
   Link: https://arxiv.org/abs/2509.07762
   In this two-part series, we present a multi-probe mass modelling method for massive galaxy clusters, designed to disentangle the contributions of individual mass components (Dark matter, intra-cluster gas, stellar masses).
13. LBT-MODS spectroscopy of young stellar objects in the distant metal-poor star forming region Sh2-284: Stellar and accretion properties
   Source: astro-ph.GA (Astrophysics of Galaxies)
   Link: https://arxiv.org/abs/2607.22533
   We present a spectroscopic survey of young stellar objects (YSOs) in Sh2-284, a distant (~4.5 kpc), low-metallicity (Z~1/3 Zsun) star-forming region (SFR) toward the Galactic anticenter.
14. Detecting habitable exoplanet atmospheres with LIFE, the Large Interferometer for Exoplanets
   Source: astro-ph.EP (Earth and Planetary Astrophysics)
   Link: https://arxiv.org/abs/2607.21683
   A key goal of astronomers with the next generation telescopes is to detect signs of life in exoplanet atmospheres.
15. High-Energy Neutrinos from Cosmic-Ray Scatterings with Supernova Neutrinos
   Source: astro-ph.CO (Cosmology and Nongalactic Astrophysics)
   Link: https://arxiv.org/abs/2508.11891
   Cosmic rays scattering with neutrinos produced in supernovae induce a flux of supernova neutrinos boosted to high energies.
16. Is S301 the Captured Companion of the Hypervelocity Star S5-HVS1?
   Source: astro-ph.GA (Astrophysics of Galaxies)
   Link: https://arxiv.org/abs/2607.22517
   Stellar binary disruptions through the Hills mechanism produce two fossils: a hypervelocity star (HVS), and a star tightly bound to the supermassive black hole.
17. JWST NIRCam Reveals the Largest Known M-dwarf Debris Disk Around TWA 10 and New Scattered-Light Observations of the TWA 25 Debris Disk
   Source: astro-ph.EP (Earth and Planetary Astrophysics)
   Link: https://arxiv.org/abs/2607.22426
   We present JWST NIRCam observations of two M-dwarf systems located in the TW Hydra association, TWA 10 and TWA 25.
18. Purely quadratic non-Gaussianity from tachyonic instability: Primordial black holes and scalar-induced gravitational waves
   Source: astro-ph.CO (Cosmology and Nongalactic Astrophysics)
   Link: https://arxiv.org/abs/2604.20063
   We investigate primordial black hole (PBH) formation in a cosmological scenario where curvature perturbations follow purely quadratic non-Gaussianity, $\zeta = A(\phi^2-langle\phi^2\rangle)$, arising from tachyonic instability in multicomponent inflationary models.
19. When Two Worlds Collide: How Collisions Between Silicate and Carbonaceous Nanograins can Drive Complex Chemistry
   Source: astro-ph.GA (Astrophysics of Galaxies)
   Link: https://arxiv.org/abs/2607.22213
   Our overall objective is to determine how collision velocity governs the interactions between silicate and carbonaceous nanograins.

Sources in this brief: astro-ph.CO (Cosmology and Nongalactic Astrophysics); astro-ph.EP (Earth and Planetary Astrophysics); astro-ph.GA (Astrophysics of Galaxies).
Selected 19 of 52 available items for this weekly brief.