Maintenance and upgrades: the 2016 summer shutdown

Sergei Nagaitsev

Sergei Nagaitsev

Every year, the summer shutdown of the accelerator complex provides a short break in Fermilab accelerator operations. It allows for a brief time to reflect on the successful operation of the past year. With the achievement of performance metrics and internal goals fresh in our minds, the summer shutdown is the period where we look ahead to next year’s goals. The machine improvements and installation of new beamlines, components and systems look good on paper, but the real test follows during machine operation.

The summer shutdown also provides a chance for some much needed system maintenance. Many systems have been running all year with minimal upkeep. Some systems have been patched up to keep them operational until the anticipated shutdown. Power supply, vacuum, sump, lighting, cooling, ventilation, water supply and many more systems – all need to be maintained.

The accelerator operators have an opportunity to work on projects, training and procedures. Some operators will help out support groups with various tasks and expand their system knowledge. The addition of the new interlock region in the Main Injector could allow Booster Neutrino Beamline startup several weeks early. This will provide the operators with some time to focus on the Linac and Booster operation while work continues in Main Injector.

For some operators, a multiweek break from shiftwork and a chance to renormalize to working days is a welcome change. In any case, the machine startup in November, with new challenges and goals, will test even the experienced operators.

The 2016 summer shutdown will start Aug. 1 and will last 15 weeks. Here’s a brief summary of what we’ll be doing:

Accelerator shutdown summary

The Proton Source Group will install the first of five full (56-cell) Marx modulators, or high-voltage pulse generators. These solid-state modulators will replace the aging tube-driven system that was originally installed in the late 1960s.

The Booster Group will focus on installing two new radio-frequency power stations. This work also involves substantial gallery modification to make space for the two new driver and modulator stations.

Three major jobs in the Recycler Ring will take place during the shutdown. One is to upgrade Recycler vacuum pumps. It will span approximately one-third of the ring circumference. A second task is to install the Recycler collimator. This will be the cornerstone of providing regular 700-kilowatt-beam operations to the complex. The collimators are designed to absorb off-momentum beam in a controlled manner, thus containing losses in the machine in a designated area. Third, we are installing a new 2.5-megahertz RF cavity, which will rebunch the beam destined for the Muon Campus.

The NuMI Group will replace the existing beam target and perform general, shutdown-period maintenance.

A new beamline connection from the Recycler to the Muon Campus was installed in previous shutdowns. The remaining work in the Delivery Ring and new Muon Campus beamlines does not require a shutdown and will be ready to commission beam to the Muon g-2 experiment next spring.

In one sector of the switchyard, we will rework the P3 line vacuum system and install some additional diagnostic equipment in the beamline.

In the first few weeks of the shutdown, we will also test the new Booster Neutrino Beam horn in one of the service buildings. The testing needs to be done with the operational power supply since it’s the only supply that can generate the proper pulse form to commission the horn.

With technical help from the Particle Physics Division, the Technical Division and ESH&Q, the 15-week shutdown will be a safe and productive one.

Five things you should know about the Accelerator Division all-hands meeting

And here are the five most important takeaways from our July 18 all-hands meeting:

  1. We are making excellent progress towards 700-kilowatt beam power to NuMI.
  2. Many of PIP-I improvements (in the Linac and the Booster) in beam delivery have been realized already. We’re working to ensure high reliability is maintained.
  3. The Muon Campus construction is on track, and we will be ready to commission and operate beam for Muon g-2 starting in FY17.  Our effort on DOE projects (LCLS-II, PIP-II, LBNF, Muon g-2, Mu2e) is on schedule and within budget.
  4. An exciting accelerator research program with a 50-MeV electron beam at FAST is under way.
  5. We continue to do our jobs safely.

Sergei Nagaitsev is the Fermilab chief accelerator officer.