absorb.md

Jenn Wortman Vaughan

Chronological feed of everything captured from Jenn Wortman Vaughan.

paper / jennwvaughan / Jun 12

First Detection of Gaseous SiO in a Directly Imaged Companion Reveals Super-Stellar Silicon and Constraints on Formation Pathways

This paper presents the first detection of gas-phase SiO via M-band high-resolution spectroscopy (CRIRES+) in the directly imaged companion TWA 5 B, opening a new window into refractory-element chemistry in substellar atmospheres. The measured super-stellar Si/H with simultaneously measured CO, H2O, and SiO abundances constrains the formation pathway—favoring core-accretion beyond the CO snowline or gravitational instability with solid enrichment—while the high SiO abundance rules out significant magnesium-silicate cloud condensation, establishing SiO as a key tracer of cloud properties in hot gas giants.

exoplanet-atmosphereshigh-resolution-spectroscopysilicon-chemistrydirect-imagingcloud-formationcore-accretion
“First robust detection of gaseous SiO in a directly imaged companion atmosphere via M-band high-resolution spectroscopy”
paper / jennwvaughan / May 31

Drain-Vortex Optimization Tops CEC 2017 Benchmarks by Modeling Candidate Solutions as Fluid Particles in a Multi-Drain Vortex Field

Drain-Vortex Optimization (DVO) is a new population-based metaheuristic that abstracts candidate solutions as particles in a multi-drain free-vortex flow field, decomposing motion into radial attraction and tangential rotation. A three-phase switching mechanism governs exploration, spiral inward motion, and localized exploitation based on normalized distance to an assigned drain center. Benchmarked against seven established algorithms (PSO, GWO, WOA, SCA, AOA, EO, SVOA) with a rigorous calibration-validation split, DVO achieves the best Friedman rank on both CEC 2017 (1.67) and CEC 2022 (2.13), though it underperforms on simple scalable classical functions and small constrained engineering designs.

metaheuristic-optimizationevolutionary-computingswarm-intelligencepopulation-based-searchbenchmark-evaluationgpu-computingnature-inspired-algorithms
“DVO achieves the best mean log10 error on 34 of 58 cases on CEC 2017 and the best Friedman average rank of 1.67 among all tested algorithms.”
paper / jennwvaughan / May 31

MINERvA's High-Statistics νμ CC1π⁺ Measurement Exposes Systematic Failures in Modern Pion Production Models

The MINERvA collaboration presents high-statistics differential cross-section measurements of muon neutrino charged-current single pion production on scintillator, using 91,843 selected events and a novel Michel electron-based technique that extends pion detection down to zero kinetic energy threshold. Comparisons against multiple neutrino event generators reveal that no current model adequately describes the full phase space: discrepancies reach up to 15% in muon observables and 20% in pion observables, concentrated in the bulk of the kinematic distributions rather than the tails. These systematic model failures have direct implications for next-generation neutrino oscillation experiments (e.g., DUNE, Hyper-K), where CC1π⁺ interactions are a significant background and cross-section modeling precision is critical.

neutrino-physicsparticle-physicscross-section-measurementpion-productionminerva-experimentneutrino-oscillationhigh-energy-physics
“Modern neutrino event generators are discrepant with MINERvA CC1π⁺ data by up to 15% in muon kinematic observables and up to 20% in pion kinematic observables.”