RAM-SCB updates

August 2023

As of August 8, 2023, the Ring current - Atmosphere interactions Model with Self-Consistent magnetic (B) field, RAM-SCB version 2.2 is available to the community through the CCMC Runs-On-Request (ROR) service.

RAM-SCB is a unique code that combines a large-scale kinetic model of ring current plasma with a three-dimensional (3-D) force-balanced model of the terrestrial magnetic field. The kinetic portion, RAM, yields bounce-averaged distribution functions for major ion species (H+, O+, and He+ by default) and electrons as a function of azimuth, radial distance, energy, and pitch angle. The domain is a circle in the Solar-Magnetic (SM) equatorial plane (2 to 6.5 Re by default). It has an energy range of approximately 100 eV to 400KeV and equatorial pitch angle range from 0 to 90°. The SCB model balances the J × B force with the divergence of the general pressure tensor to calculate the magnetic field configuration within its domain. The two codes work in tandem, with RAM providing anisotropic pressure to SCB and SCB returning the self-consistent magnetic field through which RAM plasma is advected. The code is highly configurable, enabling a wide range of scientific investigations and outputs.

This RAM-SCB ROR version is configured to use the Kp-dependent Volland-Stern electric field and a Kp-dependent plasma boundary model and can be run for any date from 1958 to present. The user-configurable options for ROR are the outer boundary of SCB (centered dipole or T89), and whether the magnetic field is self-consistent (i.e., uses SCB) or the model applied at the boundary. The output includes equatorial ring current pressure for all modeled species and equatorial differential fluxes across the full domain (as a function of position, energy, and pitch angle), each saved at 5-minute cadence. The SCB morphology is saved at hourly cadence. Automated summary plots include pressure, flux, and the predicted Dst index at 1-minute cadence.