September 8, 2014
Last week, the latest step in our Accelerator Readiness Review (ARR) took place. This process is designed to ensure that when we start to operate a new aspect of the accelerator or the experimental hall infrastructure, we are properly prepared to do so. During the spring running of 2014, the gains from the rigor applied to this process was reflected in the success we actually enjoyed in switching on and transporting beam all the way through the accelerator. The key performance parameters achieved subsequently led to the formal award on July 30 of CD-4A, “ the accelerator is ready for operations,” for the 12 GeV CEBAF Upgrade Project.
The ARR had been designed by ESH&Q, in conjunction with the accelerator and physics divisions, to be phased. Just those components about to come into play are reviewed in each phase of the process. Phase I was all about the accelerator. Phase 2 brought in Hall A and its experimental apparatus as well. Phase 3 introduced Hall D commissioning and Hall B (non-project) for running. All phases have been enormous successes for the laboratory, and this latest phase was no exception. In his letter to me, the external Chair of the review, Roger Erickson, from SLAC, emphasized that, “The committee recommends that JLab 's internal work control, configuration management, and tracking processes be used for managing the remaining work,and that the JLab management and the DOE Site Office approve the scheduled programs, subject to the completion of that work. The ARR Team has validated the effectiveness of these internal processes in the Phase 1B and Phase 2 readiness reviews. The Team believes that the internal checkout and approval processes are sufficient to ensure safe and effective commissioning and beam Operation going forward.” There are many who contributed to this continuing success; they are to be congratulated!
Considerable work has been accomplished since the scheduled accelerator shutdown began in early May. The Utilities Infrastructure Modernization (UIM) project was approved and funded in the spring at the full level of $29 million. Integrating this work with the ongoing work in the accelerator and experimental halls was a key part of minimizing the impact on the experimental program. With some compression of the checkout work, all the goals were achieved. In particular, a substantial fraction of the accelerator and end station electrical distribution system has been upgraded and a new substation added. In addition, some modifications have been made to the cooling tower network, which will avoid future outages while allowing future necessary exchanges of several cooling towers.
The past several months have also seen the refurbishment of the Hall D refrigerator. This appears to have been a major success, and the magnet has been cooled down and operated with 1200 amps for several days.
At present, the cryogenics systems are preparing to go into full operation for support of the accelerator. The goal is to bring the accelerator up during this month. Initially, the beam will be low intensity “tune” beam, which minimizes the potential for damage during commissioning. The energy will be about 10 GeV in 5.5 passes to send beam towards Hall D, 7.3 GeV for Hall A and perhaps 1.8 GeV for Hall B. Tests will also be made with other beam parameters, including a hydrogen target boiling test in Hall A.
Then during the course of the next couple of months, the beam parameters will progress and the photon beam into Hall D will be commissioned. This will enable the commissioning of the Hall D detector with beam. [Already the GlueX team has seen tracks of cosmic rays curved in the solenoidal magnetic field.] Also among the goals will be the completion of a 12 GeV upgrade project CD-4B key performance parameter. We anticipate lots of excitement as we push towards the physics with 11 GeV an expectation, perhaps for Thanksgiving. You can even find the following words on one of Arne Freyberger’s transparencies from a recent meeting: “Owl shifts and weekends, if not needed for CEBAF commissioning efforts, could be utilized for Physics operations …….”
We are looking forward to an exciting Fall Run.