Objectives of the SMALL Project

Even though 70% of the Earth's surface is below L=2, no large area 2D array is presently deployed in this region.

There have been temporary small arrays and chains set up but at present there is only one north-south chain passing through this region, the Circum-pan Pacific Magnetometer Network (CPMN) [PI: K. Yumoto] which effectively includes the easternAustralian chain.

The remaining stations at these latitudes are sufficiently separated that they can be scarcely thought to provide a chain of stations in any direction and certainly there is no region sufficiently instrumented to be considered to have a 2-D array of magnetometers. China presents us with our first opportunity to develop a full 2-D magnetic array at low latitudes.

Our scientific objectives are :

to determine how Pi 2s are produced by substorms
to determine how Pc 3,4 magnetic pulsation energy enters the magnetosphere and propagates to low latitudes
to understand the dynamics of the magnetosphere during magnetic storms using the plasma mass density estimated from eigen-frequencies of magnetospheric field lines from cross-phase and cross-power analysis
to understand how magnetospheric processes and solar wind-magnetosphere coupling affects the equatorial electrojet

The technical objectives of the SMALL project center on improving ground magnetic records with high temporal resolution digital recording and accurate timing at low cost. The goal was to develop an accurate, low cost, high precision and accurately timed digital field magnetometer with up to 6 month data storage capability and to cut the cost of the robust magnetometer and its data system from ~ $15K to ~ $6K per unit.