A5016694665- Solar and Space Plasma Dynamics
- Ionosphere and magnetosphere dynamics
- Geomagnetism and Paleomagnetism Studies
- Astro and Planetary Science
- Stellar, planetary, and galactic studies
- Geophysics and Gravity Measurements
- Solar Radiation and Photovoltaics
- Earthquake Detection and Analysis
- Spacecraft Design and Technology
- Gamma-ray bursts and supernovae
- Planetary Science and Exploration
- Space exploration and regulation
- Magnetic confinement fusion research
- Meteorological Phenomena and Simulations
- Fluid Dynamics and Turbulent Flows
- Astronomy and Astrophysical Research
- Reservoir Engineering and Simulation Methods
- Global Energy and Sustainability Research
- Radio Astronomy Observations and Technology
- Plasma Diagnostics and Applications
- Space Science and Extraterrestrial Life
- Spacecraft and Cryogenic Technologies
- Photovoltaic System Optimization Techniques
- Lattice Boltzmann Simulation Studies
- History and Developments in Astronomy
University of Michigan
2016-2025
Goddard Space Flight Center
2023
Space (Italy)
2023
Aalto University
2021
State Street (United States)
2019
National Oceanic and Atmospheric Administration
2017
Michigan United
2014
High Altitude Observatory
2000-2003
NSF National Center for Atmospheric Research
2000-2003
University of Illinois Urbana-Champaign
2000-2003
The Space Weather Modeling Framework (SWMF) provides a high‐performance flexible framework for physics‐based space weather simulations, as well various physics applications. SWMF integrates numerical models of the Solar Corona, Eruptive Event Generator, Inner Heliosphere, Energetic Particles, Global Magnetosphere, Radiation Belt, Ionosphere Electrodynamics, and Upper Atmosphere into coupled model. components can be represented with alternative models, any physically meaningful subset used....
We present a new version of the Alfven Wave Solar Model (AWSoM), global model from upper chromosphere to corona and heliosphere. The coronal heating solar wind acceleration are addressed with low-frequency wave turbulence. injection energy at inner boundary is such that Poynting flux proportional magnetic field strength. three-dimensional topology simulated using data photospheric measurements. This does not impose open-closed boundaries; those develop self-consistently. physics includes:...
As observed in Thomson-scattered white light, coronal mass ejections (CMEs) are manifest as large-scale expulsions of plasma magnetically driven from the corona most energetic eruptions Sun. It remains a tantalizing mystery to how these erupting magnetic fields evolve form complex structures we observe solar wind at Earth. Here, strive provide fresh perspective on post-eruption and interplanetary evolution CMEs, focusing physical processes that define many interactions ejected with its...
Coronal mass ejections (CMEs) were discovered in the early 1970s when space-borne coronagraphs revealed that eruptions of plasma are ejected from Sun. Today, it is known Sun produces eruptive flares, filament eruptions, coronal and failed eruptions; all thought to be due a release energy stored magnetic field during its drastic reconfiguration. This review discusses observations physical mechanisms behind this activity, with view making an assessment current capability forecasting these...
We present a three-dimensional numerical magnetohydrodynamic simulation designed to model the emergence of magnetic flux rope passing from below photosphere into corona. For initial state, we prescribe plane-parallel atmosphere that comprises polytropic convection zone, photosphere, transition region, and Embedded in this system is an isolated horizontal located 10 photospheric pressure scale heights photosphere. The uniformly twisted, with plasma temperature inside reduced compensate for...
We present a three‐dimensional (3‐D) numerical ideal magnetohydrodynamics (MHD) model describing the time‐dependent expulsion of coronal mass ejection (CME) from solar corona propagating to 1 astronomical unit (AU). The simulations are performed using Block Adaptive Tree Solar‐Wind Roe Upwind Scheme (BATS‐R‐US) code. begin by developing global steady‐state that possesses high‐latitude holes and helmet streamer structure with current sheet at equator. Archimedean spiral topology...
We present a new compressible MHD model for simulating the three-dimensional structure of solar wind under steady state conditions. The initial potential magnetic field is reconstructed throughout computational volume using source surface method, in which necessary boundary conditions are provided by magnetogram data. our simulations powered energy interchange between plasma and large-scale turbulence, assuming that additional stored "turbulent" internal degrees freedom. In order to...
We present a three-dimensional compressible magnetohydrodynamics (MHD) model of the interaction two coronal mass ejections (CMEs). Two identical CMEs are launched in exact same direction into preexisting solar wind, second one 10 hr after first one. Our global steady state possesses high-latitude holes and helmet streamer structure with current sheet near equator, reminiscent near-solar minimum conditions. Within this system, we drive to erupt by introduction magnetic flux ropes embedded...
We present a new global model of the solar corona, including low transition region, and top chromosphere. The realistic three-dimensional magnetic field is simulated using data from photospheric measurements. distinctive feature incorporating MHD Alfvén wave turbulence. assume this turbulence its nonlinear dissipation to be only momentum energy source for heating coronal plasma driving wind. difference between efficiency in holes that closed regions because cascade rate degrades strongly...
We present a new MHD model for simulating the large-scale structure of solar corona and wind under "steady state" conditions stemming from Wang-Sheeley-Arge empirical model. The processes turbulent heating in are parameterized using phenomenological, thermodynamical with varied polytropic index. employ Bernoulli integral to bridge asymptotic speed assumed distribution index on surface. successfully reproduce mass flux Sun Earth, temperature structure, magnetic field. bimodal inner...
We numerically model the coronal mass ejection (CME) event of 2003 October 28 that erupted from AR 10486 and propagated to Earth in less than 20 hr, causing severe geomagnetic storms. The magnetohydrodynamic (MHD) is formulated by first arriving at a steady state corona solar wind employing synoptic magnetograms. initiate two CMEs same active region, one approximately day earlier preconditions for much faster CME on 28th. This second travels through rate over 2500 km s−1, driving strong...
We have developed a new three-dimensional magnetohydrodynamic (MHD) solar wind model coupled to the Space Weather Modeling Framework (SWMF) that solves for different electron and proton temperatures. The collisions between electrons protons are taken into account as well anisotropic thermal heat conduction of electrons. is assumed be accelerated by Alfvén waves. In this paper, we do not consider heating closed magnetic loops helmet streamers but address Kolmogorov dissipation waves in open...
On 2009 February 13, a coronal wave—CME—dimming event was observed in quadrature by the Solar Terrestrial Relations Observatory (STEREO) spacecraft. We analyze this using three-dimensional, global magnetohydrodynamic model for solar corona. The numerical simulation is driven and constrained observations, indicates where magnetic reconnection occurs between expanding CME core surrounding environment. focus primarily on lower corona, extending out to 3 R☉; range allows simultaneous comparison...
ABSTRACT We present a first-principles-based coronal mass ejection (CME) model suitable for both scientific and operational purposes by combining global magnetohydrodynamics (MHD) solar wind with flux-rope-driven CME model. Realistic events are simulated self-consistently high fidelity forecasting capability constraining initial flux rope parameters observational data from GONG, SOHO /LASCO, STEREO /COR. automate this process so that minimum manual intervention is required in specifying the...
We present several methods towards construction of precursors, which show great promise early predictions, solar flare events in this paper. A data pre-processing pipeline is built to extract useful from multiple sources, Geostationary Operational Environmental Satellites (GOES) and Solar Dynamics Observatory (SDO)/Helioseismic Magnetic Imager (HMI), prepare inputs for machine learning algorithms. Two classification models are presented: flares quiet times active regions strong versus weak...
MHD-based global space weather models have mostly been developed and maintained at academic institutions. While the "free spirit" approach of academia enables rapid emergence testing new ideas methods, lack long-term stability support makes this arrangement very challenging. This paper describes a successful example university-based group, Center Space Environment Modeling (CSEM) University Michigan, that Weather Framework (SWMF) its core element, BATS-R-US extended MHD code. It took quarter...
We present a three‐dimensional (3‐D) numerical ideal magnetohydrodynamics (MHD) model, describing the time‐dependent expulsion of plasma and magnetic flux from solar corona that resembles coronal mass ejection (CME). begin by developing global steady‐state model wind gives reasonable description conditions near minimum. The field possesses high‐latitude holes closed lines at low latitudes in form helmet streamer belt with current sheet equator. further reproduce fast slow speed high...
In late October and early November 2003 a series of some the most powerful solar eruptions ever registered shook heliosphere. These “Halloween storms” damaged 28 satellites, knocking two out commission, diverted airplane routes, caused power failures in Sweden, among other problems. This paper presents 4‐day end‐to‐end simulation one major events (following X17 flare) that produced geoeffective interval Halloween storm. The was carried with newly developed Space Weather Modeling Framework...
Most high-energy solar energetic particles are believed to be accelerated at shock waves driven by coronal mass ejections (CMEs). The acceleration process strongly depends on the geometry and structure of sheath that forms behind shock. In an effort understand time evolution such CME-driven shocks their relevance particle acceleration, we investigate interaction a fast CME with ambient wind means three-dimensional numerical ideal MHD model. Our global steady state model possesses...
A deep learning network, Long-Short Term Memory (LSTM) is used in this work to predict whether the maximum flare class an active region (AR) will produce next 24 hours $\Gamma$. We considered $\Gamma$ are $\ge M$, C$ and any class. The essence of using LSTM, which a recurrent neural its capability capture temporal information data samples. input features time sequences 20 magnetic parameters from SHARPs - Space-weather HMI Active Region Patches. analyzed regions June 2010 Dec 2018,...
We present a discussion of the time evolution mass and energy model coronal ejection (CME), analyzing both synthetic coronograph images three-dimensional data numerical ideal magnetohydrodynamics (MHD) simulation. Our global steady state possesses high-latitude holes helmet streamer structure with current sheet near equator, reminiscent solar minimum conditions. Within this system, we drive CME to erupt by introduction Gibson-Low magnetic flux rope that is embedded in an initial force...
We present a three-dimensional compressible magneto-hydrodynamics (MHD) simulation of the three coronal mass ejections (CMEs) 2000 November 24, originating from NOAA active region 9236. These ejections, with velocities around 1200 km s-1 and associated X-class flares, erupted Sun in period about 16.5 hr. In our simulation, magnetic field is reconstructed MDI magnetogram data, steady-state solar wind based on varying polytropic index model, are initiated using out-of-equilibrium...
Since the first discovery of an extrasolar planetary system more than a decade ago, hundreds have been discovered. Surprisingly, many these systems harbor Jupiter-class gas giants located close to central star, at distances 0.1 AU or less. Observations chromospheric 'hot spots' that rotate in phase with orbit, and elevated stellar X-ray luminosities,suggest close-in planets significantly affect structure outer atmosphere star through interactions between magnetic field magnetosphere. Here we...