were funded from a common source. This resulted in relatively few management and funding problems.
Each facility discussed in this report—synchrotron, neutron, and high magnetic field—was developed for a different purpose at a different time. Nevertheless, each has evolved into what is recognized today as the operating mode characterized as a user facility. Early synchrotron facilities had a parasitic dependence on electron accelerators. Many early neutron facilities were constructed with multiple purposes in mind (e.g., isotope preparation, as well as beam tubes for research), but facility access to outside users was limited. The National High Magnetic Field Laboratory, on yet a third evolutionary path, was created at the outset as a national user facility.
An example of the evolution of synchrotron facilities is seen in the early days of the Stanford Synchrotron Radiation Laboratory (SSRL). 1 Initially, in 1973, the NSF operated the SSRL for materials science and low-energy physics users. The SSRL had a parasitic dependence on the Stanford Linear Accelerator Center’s storage ring (SPEAR). SSRL was, in a real sense, a subfacility attached to the main accelerator facility, which was operated by the DOE’s High Energy Physics program. While much pioneering condensed-matter science was conducted at SSRL under this system, parasitic operation satisfied few users and discouraged many potential users of synchrotron radiation because of the limited availability of beam, the poor reliability of beam delivery, and the lack of user control over beam energy. These factors compromised the users’ ability to plan experiments and to do science. Nevertheless, the value of neutron and photon sources for multidisciplinary science demonstrated by these measurements led to a new generation of facilities that were dedicated to multidisciplinary use. These facilities were created either by changing the mode of operation of an existing facility, such as the 1983 transfer of SSRL from parasitic operation under DOE’s High Energy Physics program to dedicated operation under DOE ’s Office of Basic Energy Sciences, or by constructing new user facilities.
The parasitic mode of operation is still in effect for the CHESS synchrotron at Cornell, which is dependent on the CESR high-energy physics synchrotron. Both are supported by the NSF, but the prime responsibility for the CESR storage ring resides with the NSF high-energy physics program, while the materials program is responsible for the CHESS subfacility. The operational mode for the Manuel Lujan Neutron Scattering Center at the Los Alamos Neutron Science Center (LANSCE) could at first glance appear to be parasitic as well. As discussed below, a closer examination of the multiple facilities and missions of LANSCE shows this to be incorrect.
Keith O. Hodgson, SSRL director, in a presentation to the committee on November 17, 1998.