The Continuous Electron Beam Accelerator Facility, the newest national research laboratory, successfully began conducting experiments this week. One hundred scientists from across the globe are collaborating with CEBAF to conduct the first in a series of experiments that are expected to lead to a solution to the ancient puzzle of the fundamental structure of matter.
The first experiment, "The Energy Dependence of Nucleon Propagation in Nuclei as Measured in the (e, e'p) Reaction," was begun in on of CEBAF's underground experimental halls. The experiment uses CEBAF's superconducting electron accelerator, which generates a finely tuned continuous electron beam, as a probe into nuclear matter.
"This is a proud moment for the Department of Energy and for the nuclear physics research community," said Dr. Martha Krebs, Director of the Department's Office of Energy Research in Washington. "This special research facility provides a unique tool for exploring the structure of the nucleus of the atom and for dramatically increasing our understanding of how the basic building blocks of nature work."
The researchers are directing the beam at three targets made of carbon, iron, and gold. The pattern of ejected protons will be used to determine laws governing the motion of proton through nuclear matter. These laws are of great interest in their own right. They will also be used to set a baseline for the discovery of a novel feature predicted by the quark theory of nuclear matter: in special circumstances, the proton can emerge from the center of the nucleus without suffering any of the collisions with the dense nuclear medium that would normally be expected.
The experiment will take about a month to complete. This beginning represents the culmination of nearly ten years of planning, construction, assembly and testing activities on the accelerator and research equipment.
The experiment was originally proposed by groups from Argonne National Laboratory, Northwestern University, California Institute of Technology, Massachusetts Institute of Technology, Rutgers University and the University of Colorado. With the worldwide interest in the scientific program at CEBAF, the collaboration, led by Donald Geesaman of Argonne National Labortory, has grown to include 22 institutions spanning three continents.
"We are proud to have the privilege to be doing the first experiment representing the nuclear physics community," says Geesaman. "We are excited that the CEBAF program is off and running."
The laboratory, in Newport News, VA, is managed and operated for the U.S. Department of Energy by the Southeastern Universities Research Association, Inc., a consortium of 41 universities in the southeast.
To arrange a visit to the site or to receive more information, please contact Linda Ware at (757) 269-7689.