Chris Conolly looks at the concrete floor of Wilson Lab, eyeing up the numerous holes drilled by one of the contractors for the upgrade project. These one-inch holes pockmark the 10,000sf experimental hall of the Wilson Synchrotron Laboratory. In a way, these holes represent the numerous experiments conducted over the past 50 years.

In early 2019, CHESS-U will have an increased energy of the electron beam, from 5.3 to 6.0 GeV, double the current from 100 to 200 mA, and reduction of the horizontal emittance of the x-ray beam from 100nm to 30nm.

The crews are currently working in concert with each other, moving from east to west through the L-0 experimental hall.  When a new magnet assembly goes in, the crews place a new portion of shielding wall, then a new front end assembly, followed by utilities and more portions of shielding wall - creating a dance that requires strict planning while donning steel-toed boots. 

CHESS is a high-intensity X-ray source, primarily supported by the National Science Foundation, that provides users with state-of-the-art synchrotron radiation facilities for research in physics, chemistry, biology and environmental and materials sciences.

To minimize the shut down (“dark”) time, we are placing all new magnets on girders. Then, when CESR operation is stopped for the upgrade, the girders will be moved to the tunnel and fitted into the storage ring. Each of the twelve girders contains two horizontal focusing quadrupole magnets, one large combined function magnet (bends the beam trajectory and focuses the beam vertically), and four small correcting magnets.

This unit cell was repeated roughly 50 times around the CESR tunnel. A FODO-based accelerator is very flexible and the design allowed for many modes of running over the following decades, up to and including the present-day "arc pretzel" CHESS operations.