758 citations · 2.9k across the 25 of their papers we have counts for
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Implications of Different Solar Photospheric Flux-Transport Models for Global Coronal and Heliospheric Modeling
Graham Barnes, Marc L. DeRosa, Shaela I. Jones +3
The concept of surface-flux transport (SFT) is commonly used in evolving models of the large-scale solar surface magnetic field. These photospheric models are used to determine the…
Properties of Flare-Imminent versus Flare-Quiet Active Regions from the Chromosphere through the Corona II: NonParametric Discriminant Analysis Results from the NWRA Classification Infrastructure (NCI)
KD Leka, Karin Dissauer, Graham Barnes +1
A large sample of active-region-targeted time-series images from the Solar Dynamics Observatory / Atmospheric Imaging Assembly, the AIA Active Region Patch database ("AARPs", Paper…
Large-Scale Spatial Cross-Calibration of Hinode/SOT-SP and SDO/HMI
David F. Fouhey, Richard E. L. Higgins, Spiro K. Antiochos +7
We investigate the cross-calibration of the Hinode/SOT-SP and SDO/HMI instrument meta-data, specifically the correspondence of the scaling and pointing information. Accurate calibr…
Fast and Accurate Emulation of the SDO/HMI Stokes Inversion with Uncertainty Quantification
Richard E. L. Higgins, David F. Fouhey, Dichang Zhang +7
The Helioseismic and Magnetic Imager (HMI) onboard NASA's Solar Dynamics Observatory (SDO) produces estimates of the photospheric magnetic field which are a critical input to many…
On measuring divergence for magnetic field modeling
S. A. Gilchrist, K. D. Leka, G. Barnes +2
A physical magnetic field has a divergence of zero. Numerical error in constructing a model field and computing the divergence, however, introduces a finite divergence into these c…
A Comparison of Flare Forecasting Methods. IV. Evaluating Consecutive-Day Forecasting Patterns
Sung-Hong Park, K. D. Leka, Kanya Kusano +21
A crucial challenge to successful flare prediction is forecasting periods that transition between "flare-quiet" and "flare-active". Building on earlier studies in this series (Barn…
A Comparison of Flare Forecasting Methods. III. Systematic Behaviors of Operational Solar Flare Forecasting Systems
K. D. Leka, Sung-Hong Park, Kanya Kusano +21
A workshop was recently held at Nagoya University (31 October - 02 November 2017), sponsored by the Center for International Collaborative Research, at the Institute for Space-Eart…
A Comparison of Flare Forecasting Methods. II. Benchmarks, Metrics and Performance Results for Operational Solar Flare Forecasting Systems
K. D. Leka, Sung-Hong Park, Kanya Kusano +21
Solar flares are extremely energetic phenomena in our Solar System. Their impulsive, often drastic radiative increases, in particular at short wavelengths, bring immediate impacts…
The NWRA Classification Infrastructure: Description and Extension to the Discriminant Analysis Flare Forecasting System (DAFFS)
K. D. Leka, Graham Barnes, Eric L. Wagner
A classification infrastructure built upon Discriminant Analysis has been developed at NorthWest Research Associates for examining the statistical differences between samples of tw…
Does Nearby Open Flux Affect the Eruptivity of Solar Active Regions?
Marc L. DeRosa, Graham Barnes
The most energetic solar flares are typically associated with the ejection of a cloud of coronal material into the heliosphere in the form of a coronal mass ejection (CME). However…
A Comparison of Flare Forecasting Methods, I: Results from the "All-Clear" Workshop
G. Barnes, K. D. Leka, C. J. Schrijver +15
Solar flares produce radiation which can have an almost immediate effect on the near-Earth environment, making it crucial to forecast flares in order to mitigate their negative eff…
Achieving Consistent Doppler Measurements from SDO/HMI Vector Field Inversions
P. W. Schuck, Spiro Antiochos, K. D. Leka +1
NASA's Solar Dynamics Observatory is delivering vector field observations of the full solar disk with unprecedented temporal and spatial resolution; however, the satellite is in a…
The Influence of Spatial Resolution on Nonlinear Force-Free Modeling
M. L. DeRosa, M. S. Wheatland, K. D. Leka +11
The nonlinear force-free field (NLFFF) model is often used to describe the solar coronal magnetic field, however a series of earlier studies revealed difficulties in the numerical…
The Helioseismic and Magnetic Imager (HMI) Vector Magnetic Field Pipeline: Overview and Performance
J. Todd Hoeksema, Yang Liu, Keiji Hayashi +9
The Helioseismic and Magnetic Imager (HMI) began near-continuous full-disk solar measurements on 1 May 2010 from the Solar Dynamics Observatory (SDO). An automated processing pipel…
The Helioseismic and Magnetic Imager (HMI) Vector Magnetic Field Pipeline: SHARPs -- Space-weather HMI Active Region Patches
Monica G. Bobra, Xudong Sun, J. Todd Hoeksema +5
A new data product from the Helioseismic and Magnetic Imager (HMI) onboard the Solar Dynamics Observatory (SDO) called Space-weather HMI Active Region Patches (SHARPs) is now avail…
Helioseismology of Pre-Emerging Active Regions I: Overview, Data, and Target Selection Criteria
K. D. Leka, G. Barnes, A. C. Birch +4
This first paper in a series describes the design of a study testing whether pre-appearance signatures of solar magnetic active regions were detectable using various tools of local…
Helioseismology of Pre-Emerging Active Regions II: Average Emergence Properties
A. C. Birch, D. C. Braun, K. D. Leka +2
We report on average subsurface properties of pre-emerging active regions as compared to areas where no active region emergence was detected. Helioseismic holography is applied to…
Response to "Comment on `Resolving the 180deg Ambiguity in Solar Vector Magnetic Field Data: Evaluating the Effects of Noise, Spatial Resolution, and Method Assumptions'"
K. D. Leka, Graham Barnes, G. Allen Gary +2
We address points recently discussed in Georgoulis (2011) in reference to Leka et al. (2009b). Most importantly, we find that the results of Georgoulis (2011) support a conclusion…
Modelling and Interpreting The Effects of Spatial Resolution on Solar Magnetic Field Maps
KD Leka, G. Barnes
Different methods for simulating the effects of spatial resolution on magnetic field maps are compared, including those commonly used for inter-instrument comparisons. The investig…
The Role of Magnetic Topology in the Heating of Active Region Coronal Loops
J. -Y. Lee, Graham Barnes, K. D. Leka +4
We investigate the evolution of coronal loop emission in the context of the coronal magnetic field topology. New modeling techniques allow us to investigate the magnetic field stru…
Resolving the Azimuthal Ambiguity in Vector Magnetogram Data with the Divergence-Free Condition: Application to Discrete Data
Ashley D. Crouch, Graham Barnes, K. D. Leka
We investigate how the divergence-free property of magnetic fields can be exploited to resolve the azimuthal ambiguity present in solar vector magnetogram data, by using line-of-si…
A Critical Assessment of Nonlinear Force-Free Field Modeling of the Solar Corona for Active Region 10953
Marc L. DeRosa, Carolus J. Schrijver, Graham Barnes +16
Nonlinear force-free field (NLFFF) models are thought to be viable tools for investigating the structure, dynamics and evolution of the coronae of solar active regions. In a series…