TOOLS DEVELOPED BY OPERATORS
Yan Wang, Jefferson Lab 12000 Jefferson Ave, Newport News, VA 23606

Abstract
To do a good job, you need good tools. Operators atJefferson Lab play a very important role in software tooldevelopment. Working in the machine control center,
operators use computers to control the accelerator everyday. This means that operators have first-hand experienceand know exactly what they need to run the machine. In
addition to providing valuable information to the SoftwareGroup, the operators write the code for new software toolsthat will meet their needs.

Introduction
Jefferson Lab has a very large distributed computer
control system. Accelerator operators are responsible forthe safe and efficient operation of the accelerator and itssubsystems, the delivery of high quality beam to theexperimental nuclear physics program, and maintaining
accurate records of accelerator subsystems and control
room activities. The primary job of operators is to run theaccelerator from the control room. But they also have up
to 30% of their total working hours to do side projects.
Operators can pick any project they like, including
troubleshooting, planning and performing maintenanceand upgrades to accelerator subsystems, and developing
accelerator control system programs. The group leader
can also assign projects to operators. Some operators areinvolved in software development. The software tools
developed by operators make operating the accelerator
easier and more efficient.

Software Development
Operators spend 70% of their time in the control room.
During this period they run the accelerator, delivering
beam to the experiment halls. The operators use theremaining 30% of their time to work on their favorite
projects.
Tcl/Tk is a very popular programming language usedby the operators. C and C++ are also used. Operators canlearn programming skills on their own or take classes tobuild up their skills.
Tools developed include semi-automated andautomated procedures, which save time and reduce humanerror; software interlocks that monitor the machine at all
times and turn off beam when parameters are beyond
limits; small, handy scripts, that help operators get the job
done easier and faster; and an end-of-shift report thatgives a summary of the shift.

Figure 1: Jefferson Lab is in Newport News, Virginia

Figure 2: Jefferson Lab

Figure 3: Jefferson Lab Control Room

Figure 4: This screen has all the basic controls forbeam delivery and is maintained by Operations.

Figure 7: This script does injector pre-beam check,
optimization and verification.

Figure 5: This simulator helps operators understandhow to separate beam into Experiment halls by
adjusting RF separator magnitude and phase.
Figure 8: This script measures quantum efficiency forthree lasers.

Figure 6: This script allows operators to graphicallyview how one parameter affects another. Usuallyoperators use it to optimize an output while adjusting
parameters.

Figure 9: This script adjusts magnet settings foroptics tuning.

Figure 10: This script lowers the available drive
power to the RF cavities by raising the ModAnodevoltage, which saves electrical power and extends
klystron lifetime.

Figure 13: There are more than 300 RF cavities in thelinacs. This RF fault counter provides the history ofcavity trips, which gives Ops very useful
maintenance information.

Figure 14: Operators use this script to bypass/unbypass RF cavities and update/view cavity history
file.

Figure 11: This script does spin angle change, laser
spot move and beam orbit steering in the injector.

Figure 15: This script cycles the box supply magnets
in the machine.

Figure 12:The Beam Operations Objective Monitor
monitors, records and characterizes the accelerator
beam status.

Figure 16: MAXJUICE provides Operations with asoftware interlock to protect the accelerator fromexcess energy deposition. When the limit isexceeded, the beam is turned off.

*Work supported by the U.S Department of Energy,
contract DEAC05-84ER401050