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Archives, History & Records Office

Hours: By appointment Monday-Friday during regular work hours.


Archives E-mail: slacarc[@]
RM E-mail: recordsmgt[@]
Phone: (650)926-3091
Post: SLAC Archives and History Office, M/S 82, 2575 Sand Hill Road, Menlo Park, CA 94025.

Office Location: Bldg.50, Rm.122

Stanford Synchrotron Radiation Project (SSRP)

X-ray science at SLAC began with the Stanford Synchrotron Radiation Project (SSRP). SLAC's SPEAR ring was built with one tangential port to allow synchrotron radiation to come out. Without the foresight of the ring designers to do this, SSRP would probably never have come into existence.

A successful pilot project at SPEAR led to the National Science Foundation funding the SSRP which began operations in May 1974, 8 months ahead of schedule. SSRP was the first synchrotron radiation laboratory on a multi-GeV electron storage ring that was set up as a national facility to provide access to a broad spectral range -- including hard x-rays -- to a large number of users. Although limited by parasitic operation on the SPEAR colliding-beam program, research done at SSRP revolutionized x-ray science, leading to the funding of dedicated multi-GeV facilities in the US and abroad, the so-called second generation light sources

At the start, five experimental stations shared radiation from one bending magnet tangential exit port that was part of the initial construction of the SPEAR colliding-beam storage ring. What is now the Stanford Synchrotron Radiation Lightsource (SSRL) has blossomed from a small adjunct to the SPEAR particle physics program into a vital part of SLAC National Accelerator Laboratory.

Selected Timeline

1968 Bill Spicer (Stanford University) memorandum of June 18, 1968, making a very early request that Pief Panofsky consider the possibility of using "cyclotron" (later called synchrotron) radiation from the planned SLAC storage ring for solid state studies
1972 Decision is made to start a pilot project to use the synchrotron radiation at SPEAR. In January, the Center for Materials Research (CMR) at Stanford provides funds to install an ultra-high vacuum valve on a tangential port. A beryllium window assembly and other front-end components are later added to this tangential port without venting the storage-ring vacuum system. The CMR also funds the design and cost estimate for a one-port three-station facility at SPEAR. A supplementary proposal is submitted to the National Science Foundation in November to cover the costs for the pilot project, which was focused on high-resolution X-ray photoemission spectroscopy. A proposal to build and operate the facility is submitted to the NSF by PI Sebastian Doniach. Another proposal for a synchrotron facility at the Cambridge Electron Accelerator (CEA)is submitted by William Paul, Karl Strauch, and Herman Winick at Harvard University. A review committee established by the NSF makes site visits to both SLAC and the CEA and decides in favor of the SLAC proposal.
1973 Stanford Synchrotron Radiation Project (SSRP) started by Sebastian Doniach (Director) and William Spicer (Consulting Director) with funding from the National Science Foundation; the US Navy’s Michelson Lab at China Lake, California; Xerox Corporation; and Bell Telephone Laboratory. Herman Winick from the CEA joins SSRP as Associate Director.
5/1974 SSRP begins operations (8 months ahead of schedule) with 5 experimental stations sharing a beamline.
10/24-25/1974 First SSRP Users Group meeting
11/1974 The November Revolution takes center stage: On November 8th the first sharp resonance is discovered at SPEAR, beam energy required is 1.5 GeV, no x-ray experiments are possible at this beam energy, UV experiments continue. On November 11th, SSRP is given a prime shift, "experimenters [are] very happy." On November 20th a second sharp resonance is observed, beam energy required is 1.85 GeV, better for SSRP than November 8th, but still not much x-ray flux.
1975 National Science Foundation funds a second main beam line and a general expansion of laboratory facilities at SSRP.
1975 Brian Kinkaid, who played a major role in the development of the SSRP EXAFS facility, completes his Ph.D., the first to be awarded for work done at SSRP.
1976 Cullie Sparks of the Oak Ridge National Laboratory led the team that did the search for superheavy elements at SSRP in 1976. The synchrotron radiation experiments definitively showed that the claims for the presence of superheavy elements in some minerals were inaccurate.
5/1976 A second beam line with 4 additional synchrotron radiation experimental stations begins operating at SPEAR
12/1976 SSRP user community numbers almost 200 scientists from 52 different institutions, with 138 active research proposals. NSF approves SSRP expansion proposal, including new experimental hall, new beam lines, and a wiggler magnet.
4/1977 SSRP Wiggler Workshop: A three-day workshop on the subject of Wiggler magnets is held at SLAC on March 21-23, 1977, and is attended by about 60 scientists from 17 laboratories around the world.
9/1/1977 SSRP becomes Stanford Synchrotron Radiation Laboratory (SSRL)

The First Beamlines

  Experimental Station Early Users / Investigators Design/Construction Notes
1-1 4° Beam Line - UV and soft X-radiation <2keV F. Brown, R. Bachrach, S. Hagstrom (Xerox); I. Lindau, W. Spicer (Stanford University); D. Shirley (LBL) F. Brown et al. (Xerox Research Center). Soft X-ray Grazing Incidence Monochromator [Grasshopper] design by N. Lien (University of Wisconsin), funded by Xerox Research Center. Grazing-incidence Mirror by U.S. Navy Michelson Lab Operational May-June 1974
1-2 8° Rising Beam Line - UV [VUV] radiation <.3keV V. Rehn et al. (U.S. Navy Michelson Lab, China Lake); I. Lindau, W. Spicer (Stanford) V. Rehn et al. (U.S. Navy Michelson Lab). McPherson Normal Incidence Monochromator and Grazing-incidence Mirror contracted by U.S. Navy Michelson Lab Operational June 1974
1-3 X-ray Photoemission Spectroscopy (XPS) I. Lindau, S.Doniach, W.Spicer, P.Pianetta* (Stanford); P. Citrin (Bell Lab) I. Lindau (Stanford), Double crystal Monochromator design by P. Pianetta* High vacuum sample chamber and energy analyzer by I. Lindau Operational May 1974 (Also used during 1973-74 Pilot Project)
1-4 X-ray diffraction (Biology Beam Line)- Low angle diffraction camera N.Webb et al. (California Institute of Technology); I. Matsubara (University of Tokyo); K. Hodgson (Stanford) N.Webb et al. (California Institute of Technology) funded and built Grazing-incidence monochromator (curved crystal, double-focusing) with low angle diffraction camera Operational June 1974
1-5 Extended X-ray Absorption-edge Fine Structure (EXAFS) P. Eisenberger (Bell Lab); S. Doniach, B. Kincaid,* M. Weissbluth, A. Bienenstock, S. Hunter* (Stanford); F. Lytle (Boeing), D. Sayers, E. Stern (University of Washington) P. Eisenberger (Bell Lab), D. Sayers (University of Washington) Rapidly Tunable Hard X-ray Monochromator (channel-cut silicon crystal) funded by Bell Lab and Seattle Group (Boeing and University of Washington) Operational May 1974

*Graduate students

Sources (in chronological order)


Later histories and personal narratives

The Archives also holds: a video of Herman Winick giving an illustrated talk about the history of SSRP/SSRL, including time-lapse footage of the set up of Cullie Sparks' experiment; snapshots of folks at work; and further information about the X-ray science conducted here.

Photo Gallery

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Last Updated: 03/23/2023