Engineering topics
Meadors, Grant David
Publications and source records attributed to Meadors, Grant David.
Quick Approximations to LISA’s White-Dwarf Galactic Background
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WSA-Optimized Technology Readiness Level upgrade
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Validation of Space Weather Data using LISA Pathfinder historical sensor records [Slides]
LANL missions can be affected by space weather.
Gravitational-Wave Astronomy's Future Among the Stars [Slides]
Abstract not provided.
APS-IDEA National Meeting Homework: Driver Diagrams [Slides]
Abstract not provided.
Deep learning to help find continuous gravitational waves [Slides]
This presentation is a celebration of research that was mentored by Grant David Meadors during the summer. The hard work was done by the students at the ICR in Santa Fe, July 2021.
Laser Interferometer Space Antenna (LISA) Launch 2034: how LANL can engage today [Slides]
The Laser Interferometer Space Antenna (LISA) ESA-NASA mission will launch in 2034. LISA is the next generation of gravitational wave (GW) astronomy.
Forecasting the Solar Wind with Sequential Monte Carlo Assimilation of Satellite Data [Slides]
Abstract not provided.
Knowing our Sun: data fusion for optimizing space weather forecasts
Outline: Space weather: model for predicting solar wind & polarity; Particle filtering: optimization with Monte Carlo; Simulation & observation: twin tests and real data; Back to Earth: independent work in inertial confinement fusion (ICF)
Data Assimilative Optimization of WSA Source Surface and Interface Radii using Particle Filtering
TheWang-Sheeley-Arge (WSA) model estimates solar wind speed and interplanetary magnetic field polarity in the inner heliosphere using global photospheric magnetic field maps. WSA employs the Potential Field Source Surface (PFSS) and Schatten Current Sheet (SCS) models to determine the Sun's global coronal magnetic field. The PFSS and SCS models are connected through two radial parameters, the source surface and interface radii, which specify the overlap region between the inner SCS and outer PFSS models. Though both radii values are adjustable, they have typically been fixed to 2.5 solar radii. Our work highlights how solar wind predictions improve when the radii are allowed to vary over time. Data assimilation using particle filtering (sequential Monte Carlo) is used to infer optimal values over a fixed time window. Solar wind model predictions and satellite observations are compared with a newly developed quality-of-agreement prediction metric. The agreement metric between the model and observations is assumed to correspond to the probability of the two key WSA model parameters, the source surface and interface radii, where the highest metric value implies the optimal radii.We find that the optimal particle filter values of solar radii can perform twice as well as standard values for an exploratory period during Carrington Rotation 1901, with these values also reducing nonphysical kinking effects seen in solar magnetic field lines. Data assimilation choices of input realization and time frame have implications for variation in the solar wind over time. We present this work's theoretical context and practical applications for prediction accuracy.
Discovering hidden signals from gravitational waves and our universe [Slides]
The definition of a Gravitational-wave observatory: a transducer, from oscillations in the metric of space to observables (electromagnetic, acoustic, . . .). The presentation provides insights into the gravitational-wave cosmos performed at various observatories.