Hilary Mason

DFT Functional Choice Impacts Electron Scattering Cross Sections and Target Properties of Nitric Oxide

This work investigates the influence of various Density Functional Theory (DFT) functionals and basis sets on the calculated low-energy electron scattering cross sections of Nitric Oxide (NO). The study found that the choice of DFT functional and basis set significantly affects NO's target properties and the resulting electron scattering cross sections, particularly resonance features. A recommended computational protocol using $\omega$B97X-D3/aug-cc-pVTZ for geometry optimization and aug-cc-pVQZ for target properties is proposed for accurate R-matrix modeling.

JWST SPURS Reveals Diverse ISM Kinematics and Covering Fractions in z=5-9 Galaxies

Deep JWST grating spectroscopy of six luminous galaxies at z=5-9 reveals significant diversity in interstellar medium (ISM) covering fractions (0.2-0.9) and kinematics, characterized by velocity centroids from +70 to -140 km/s. Predominantly blueshifted high-ionization absorption indicates multiphase outflows across the sample. However, half the galaxies, especially lower mass and higher sSFR systems, show low-ionization centroids near systemic velocity, contrasting with lower redshift trends and potentially indicating inefficient entrainment or infalling gas.

Ergodicity-Based ACF Estimation Resolves Interval-Length Dependence in Solar Wind Turbulence Scales

Standard autocorrelation function (ACF) estimators for solar wind turbulence produce integral timescales that artificially depend on the observation interval length, because they fail to capture true long-lag behavior. The authors introduce a new ACF estimator with superior ergodic convergence that eliminates this interval-length dependence, enabling unambiguous estimation of integral and correlation scales. Applied to magnetic fluctuations near 1 AU, the method provides robust scale estimates grounded in ergodic theory rather than heuristic windowing.

Generalizing Perron--Frobenius Theory and Eigenvector Centrality for Complex-Valued Network Weights

This paper extends the Perron--Frobenius (PF) theorem and associated eigenvector centrality measures to networks with complex-valued edge weights, which are common in fields like quantum information and machine learning. The authors generalize the PF theorem for complex matrices, establish interconnections between these generalizations, and introduce novel centrality measures applicable to complex-weighted networks, demonstrating their utility with examples from electron transport and communication networks.

A Bounded-Confidence Model of Opinion Dynamics with Adaptive Interaction Probabilities

Probing Solar Wind Structures with Solar Energetic Particle Observations from Solar Orbiter

Electron momentum densities from QSGW and $G^0W^0$: Revealing the role of many-body effects within the reduced density matrix

Prospects for Astrobiology and Technosignature Searches with the Vera C. Rubin Observatory Legacy Survey of Space and Time

X-ray Pulse Profile Modeling of a 448-Hz Accreting Millisecond Pulsar Yields Large Neutron Star Mass-Radius Constraints via NICER+IXPE Polarimetry

Combined NICER and IXPE observations of the newly discovered accreting millisecond pulsar SRGA J144459.2-604207 (spinning at 448 Hz) were analyzed using relativistic ray-tracing pulse profile modeling to constrain neutron star mass and radius. The best-fit model features two independent, geometrically distinct hotspots — a large, cool primary near the north rotational pole dominating unpulsed emission, and a smaller, hotter secondary in the southern hemisphere driving the pulse profile shape — with a jointly favored large mass and radius. However, multiple parameters rail against prior bounds, signaling potential model inadequacy, and results show sensitivity to the joint-analysis methodology employed, undermining confidence in the inferred parameters. Future simultaneous, multi-band polarimetric observations are expected to tighten constraints substantially.

Adaptive Edge Weights in Bounded-Confidence Opinion Models Reveal Network-Dependent Polarization Dynamics

This paper extends the classical Deffuant–Weisbuch (DW) bounded-confidence model of opinion dynamics by introducing heterogeneous, adaptive edge weights on networks, where interaction probabilities between agents evolve based on prior agreement history. The authors provide formal convergence guarantees and characterize the long-time behavior of edge weights and the model's "effective graph" — a time-varying subgraph of mutually receptive agents. A key empirical finding is that adaptive edge weights have qualitatively opposite effects depending on network density: they accelerate convergence on dense networks but slow it on sparse ones under small confidence bounds.

High-Resolution Spectroscopy Is Indispensable for Characterizing Stellar Transient Ejecta Dynamics

Using the optical transient NGC 300 OT2008-1 as a test case, this study demonstrates that low-resolution (LR) spectra are fundamentally insufficient for characterizing the physical dynamics of stellar transients — not merely less precise, but actively misleading. A direct comparison of near-simultaneous FORS (LR) and UVES (HR) spectra taken one day apart shows that HR data reveals a richer emission line inventory, complex ejecta geometry, and velocity structure that LR data cannot resolve. The authors argue that LR and HR spectra serve complementary but distinct roles: LR enables bolometric/SED-level analysis, while HR is required for dynamics, precise line identification, and physically realistic modeling. Sustained HR spectroscopic monitoring campaigns are advocated as the standard approach for transient astrophysics within the local group.

Generative AI for Visualizing Highway Construction Hazards Through Synthetic Images and Temporal Sequences

Kinetics of Mycoprotein Production from Alternative Carbon Substrates

Power, Prescription, and Postpositivism: Considerations for collecting and representing neurodiversity demographic information in physics education research

First evidence of neutrino absorption on argon using $^{8}$B solar neutrinos in DEAP-3600

No Measurable Changes in Radio and X-ray Emission Surrounding Glitches in the Young Pulsar PSR J2229+6114