It was first announced that the particle accelerator had reached the end of
its career in October 1992, following several reprieves as new areas of research were entered. All told, the accelerator made major contributions in four distinct areas of research: high-energy particle physics, nuclear heavy-ion physics, medical research and therapy, and space-related studies of radiation damage and heavy particles in space.
On hand for the final "turn-off," which was videotaped for inclusion in an
LBL-produced video about the Bevalac, were many of the people instrumental in
the building and start-up of the accelerator. Among these were William Brobeck,
chief designer of the Bevatron, Bruce Cork, Walt Hartsough, Warren Chupp, and
Owen Chamberlain, who received a Nobel prize for his discovery of the
anti-proton at the Bevatron, joined the group, as did project collaborator
Clyde Wiegand. Rick Gough, acting AFRD director; William Barletta, new AFRD
director as of March 1; Nuclear Science Division director James Symons; Klaus
Berkner, associate laboratory director for operations; and Herb Steiner, chair
of the UC Berkeley Physics Department, were all present for the festivities.
Ben Feinberg, Bevalac operations program head, and Fred Lothrop, former
scheduling coordinator, were among the many other present and former Bevalac
staff and experimenters on hand.
One touching moment came just after Lofgren shut the machine down. "Taps"
wafted out over the PA system.
Shortly after the beam was turned off, power to the magnets was turned off by
Warren Faust, head of the motor-generator crew, and retired engineer Harold
Vogel. While the motor generators audibly wound down, the group was in
telephone contact with former motor-generator engineer Bob Frias.
Feinberg noted that the shutdown came 39 years to the week after beam was
first circulated in the Bevatron. The last experiment to be run was led by a
collaboration from Japan, headed by Isao Tanihata. The experiment was to study
the properties beams of radioactive isotopes created at the Bevatron.
The shutdown of the Bevatron was stage two in the Bevalac shutdown. The
SuperHILAC was turned off for the last time on Dec. 23, 1992; since Jan. 4,
only the Bevatron has been operational.
The next stage, Feinberg says, is to "stand down and secure" the facility,
which will leave it in a safe condition. This phase will extend through
September 1994, and will involve about 30 people. Following this stage will be
a period which he describes as "an extended transition process to undertake the
planning and characterization necessary to come up with a cost effective and
efficient plan to decommission and decontaminate the facility."