The Versatile Electron Radiation Belt code (VERB) was developed by the Space Environment Modeling Group SEMG (http://rbm.epss.ucla.edu/) at the University of California, Los Angeles. The model has been described in Shprits et al., 2009, and Subbotin et al., 2010. It solves the Fokker-Planck equation for electron PSD [Schulz and Lanzerotti, 1974, Shprits et al., 2008b, Subbotin and Shprits, 2009]. The equation is solved using a finite differences approach and an implicit numerical scheme. The stability of such scheme is independent of the used time step. Following the approach used for the solution without mixed diffusion terms, described by Subbotin and Shprits, the equation (1) is split into radial diffusion and local (energy, pitch angle, mixed) diffusion. The further separation of energy and pitch angle diffusion is impossible due to the existence of the mixed diffusion terms. Therefore, the implicit solution requires inversion of a model matrix of the 2-D operator on each time step. Inversion of such a big matrix is a quite time consuming computational operation, which is not required for the solution of the Fokker-Planck equation in the explicit formulation [Press et al., 1992]. However, the implicit scheme allows to use a longer model time step, while the time step in explicit scheme is limited by the Courant-Friedrichs-Lewy stability condition [Courant et al., 1928; Press et al., 1992], and the overall computational wall clock time with implicit scheme is lower.
The VERB code is written in C++, and was designed for use on a single-CPU computer and conforms to the C++ 2011 standard. The cross-platform code supports the compilation on various systems (Linux, Windows, Mac OS). Please see the link to the model description for more details
To improve the storm-based studies, the realistic field model will be included in the further model developments.
Inputs to VERB vary depending on the requested simulation. At a minimum, the user may just specify Kp and constant boundary conditions. GOES 13-15 measurements from the EPEAD (Energetic Proton, Electron and Alpha Detector) instruments may be used to scale the outer boundary in L-shell, which requires input of solar wind data in order to run the requested magnetic field model. These inputs are automatically generated for the requested model.
Outputs include the electron PSD (Phase Space Density) on the model grid, and optionally the invariant flux (electron flux computed from a dipole magnetic field model).
Model is time-dependant.
2016-08-04 Initial model installation 2016-09-08 Revision where model can run in separate instances 2016-10-27 Pre-calculated diffusion coefficient files available for reuse when the same grid is requested 2017-06-27 Use Matlab instead of Octave for interface scripts and plotting 2017-10-26 VERB code using OpenMP multi-threading
- Magnetosphere / Inner Magnetosphere / RadiationBelt
Space Weather Impacts
- Near-earth radiation and plasma environment (aerospace assets functionality)
- Shprits, Yuri Y, Scot R Elkington, Nigel P Meredith, Dmitriy A Subbotin (2008), Review of modeling of losses and sources of relativistic electrons in the outer radiation belts: I. Radial transport
- Shprits, Y. Y., D. Subbotin, and B. Ni (2009), Evolution of electron fluxes in the outer radiation belt computed with the VERB code
- Subbotin, D., Y. Shprits, and B. Ni (2010), Three-dimensional VERB radiation belt simulations including mixed diffusion
- Subbotin, D. A., and Y. Y. Shprits (2009), Three-dimensional modeling of the radiation belts using the Versatile Electron Radiation Belt (VERB) code
- Subbotin, D. A., Y. Y. Shprits, M. Gkioulidou, L. R. Lyons, B. Ni, V. G. Merkin, F. R. Toffoletto, R. M. Thorne, R. Horne, and M. K. Hudson (2011), Simulation of the acceleration of relativistic electrons in the inner magnetosphere using RCM‐VERB coupled codes
- Shprits, Y., D. Subbotin, B. Ni, R. Horne, D. Baker, and P. Cruce (2011), Profound change of the near‐Earth radiation environment caused by solar superstorms
- Kyung-Chan Kim, Yuri Shprits (2013), Long-term relativistic radiation belt electron responses to GEM magnetic storms
- Shprits, Y., A. Kellerman, D. Kondrashov, and D. Subbotin (2013), Application of a new data operator-splitting data assimilation technique to the 3-D VERB diffusion code and CRRES measurements
- Michael Schulz, Louis J. Lanzerotti (book), Particle Diffusion in the Radiation Belts, Physics and Chemistry in Space
- Drozdov, A. Y., Y. Y. Shprits, K. G. Orlova, A. C. Kellerman, D. A. Subbotin, D. N. Baker, H. E. Spence, and G. D. Reeves (2015), Energetic, relativistic, and ultrarelativistic electrons: Comparison of long-term VERB code simulations with Van Allen Probes measurements
Code Languages: C++, Matlab
- VERB real time forecast
- Space Environment Modeling Group
- Model Details (to be replaced with a permanent home)
- Yuri Shprits, UCLA (Model Developer)
- Adam Kellermen, UCLA (Model Contact)
- Lutz Rastaetter, NASA GSFC CCMC (CCMC Model Host)
- Yihua Zheng, NASA GSFC CCMC (CCMC Model Host)
In addition to any model-specific policy, please refer to the General Publication Policy.