• A.P. Shishlo, C.K. Allen, J. Galambos, T.A. Pelaia
  ORNL, Oak Ridge, Tennessee
• P. Chu
  SLAC, Menlo Park, California

XAL is a Java programming framework for building high-level control applications related to accelerator physics. The core of XAL consists of a GUI framework to provide common “look and feel” and functionality for all XAL applications, a hardware representation of the machine for connectivity and control, and a beam simulation model termed the "online model" for model reference and comparison to the hardware operation. The structure, details of implementation, and interaction between these components, auxiliary XAL packages, and applications are discussed. A general overview of applications created for the SNS project and based on XAL is presented.

• K.A. Brown, L. A. Ahrens, J. Beebe-Wang, J. Morris, S. Nemesure, G. Robert-Demolaize, T. Satogata, V. Schoefer, S. Tepikian
  BNL, Upton, Long Island, New York

The on-line models for RHIC and the RHIC pre-injectors (the AGS and the AGS Booster) can be thought of as containing our best collective knowledge of these accelerators. As we improve these on-line models we are building the framework to have a sophisticated model-based controls system. Currently the RHIC on-line model is an integral part of the controls system, providing the interface for tune control, chromaticity control, and non-linear chromaticity control. What we will discuss in this paper is our vision of the future of the on-line model environment for RHIC and the RHIC pre-injectors. Although primarily these on-line models are used as Courant-Snyder parameter calculators using live machine settings, we envision expanding these environments to encompass many other problem domains. We will also discuss the importance of the modeling infrastructure and organization as well as interfacing to controls, power supply, and magnetic measurement infrastructure and organizations. The model engines themselves will be discussed and our own evolution toward incorporating more sophisticated simulation filters, such as PTC and UAL, into the on-line model infrastructure.