SNS Application Programming Plan

The architecture for Spallation Neutron Source accelerator physics application programs is presented. These high level applications involve processing and managing information from the diagnostic instruments, the machine control system, models and static databases; they will be used to investigate and control beam behavior. Primary components include an SNS global database and Java-based Application Toolkit, called XAL. A key element in the SNS application programs is time synchronization of data used in these applications, due to the short pulse length (1 ms), pulsed (60 Hz) nature of the device. The data synchronization progress is also presented.