Use of a virtual accelerator for a development of an accelerator control system

The concept of virtual accelerator is introduced to develop beam control application programs in the KEKB accelerator control system. A virtual accelerator is a computer process which simulates behavior of a beam in an accelerator and responds to the accelerator control program under development in a same way as an actual accelerator does. Users of the virtual accelerator can test their control algorithm and user interface without affecting the operation of the accelerator. EPICS (Experimental Physics and Industrial Control System) jointly developed by LANL and APS/ANL will be used as a basis of the KEKB accelerator control system. In the EPICS based control system, a device is represented as a collection of records in a EPICS runtime database. A control program on a host computer can access devices in the system only through names of record fields, called `channels´. This abstraction allows us to construct a virtual accelerator control system. Channel access interfaces were implemented into the modeling program SAD to realize this idea. A sample application of the method will be also presented