Synchrotron light sources have undergone three generations of development in the last two
decades. The National Synchrotron Light Source (NSLS) at Brookhaven National Laboratory has two
"second generation" storage rings that currently provide the world's most intense sources of photons
in the VUV and X-ray spectral ranges. There are almost 90 beam lines serving a community of 2600
scientists from 370 institutions. They are engaged in basic and applied research in physics, chemistry,
biology, medicine, materials science and various technologies.
When design of the NSLS began in 1977, emphasis was given to the stability of the concrete
slab on which the storage rings and experimental beam lines were placed. Stability is the result of
controlling: . vibration from sources internal and external to the building, . thermal effects of air and water temperature variations, . foundation settlement and contact between the slab and underlying subsoil.
With the advent of new research where highly focused beams of x-rays must be placed on increasingly
smaller targets located 35 meters or more from the source, and the development of x-ray lithography
with resolutions approaching 0. 1 micron at chip exposure stations, even greater attention to stability
is required in building designs.