Memorial Resolution:
Joseph Ballam
(1917-1997)
Joseph Ballam, Emeritus
Professor at the Stanford Linear Accelerator Center
(SLAC) and the founding Associate Director of SLAC's
Research Division, a position he held for 19 years, died
December 14, 1997 of emphysema related complications at
the age of 80. He served Stanford University for 26 years
until his retirement in 1987.
Ballam was born in Boston
on January 2, 1917. He entered the University of Michigan
in 1935 and received his BS in Physics four years later.
The stimulating atmosphere at Ann Arbor, and its large
community of prominent physicists from the U.S. and
abroad, kindled his enduring interest in basic physics.
After one semester at MIT, Ballam commenced war work by
joining the Navy's Bureau of Ships, working on underwater
mine sweeping and on infrared signaling devices and other
naval problems. After the war Ballam returned to graduate
studies at the University of California at Berkeley and
did his Ph.D. work in cosmic rays. His thesis was on the
proton component of cosmic rays at sea level. At Berkeley
Ballam worked initially with the on-campus cloud chamber
group of Professors Brode and Fretter; after two years he
joined the UC Radiation Laboratory. After receiving his
Ph.D. in Berkeley, Ballam became an Assistant Professor
at Princeton University where he did cloud chamber work
in cosmic rays at high altitude and at the Brookhaven
National Laboratory's Cosmotron, principally on strange
particles. Ballam then joined the senior faculty at
Michigan State University. From there he continued work
at the Cosmotron, using a propane bubble chamber for pion
scattering experiments.
When SLAC was authorized
in 1961, Ballam was persuaded to join its senior
technical staff as an associate professor and he
participated in the early planning of the experimental
program. The promise demonstrated at Berkeley by Ballam's
organizational ability and deep knowledge of physics was
of immediate value to the early evolution of SLAC.
Theoretical calculations predicted that high-energy
photon interactions would produce very large yields of
secondary beams that could compete successfully with the
hadron beams produced by then existing and planned proton
machines. Moreover, because of the high pulse repetition
rate in the Stanford Linear Accelerator, the use of such
beams might offer singular advantages. Ballam initiated
work to develop an experimental program utilizing such
beams at SLAC. He extended and confirmed these
predictions through measurements at the then operating
Cambridge Electron Accelerator and subsequently converted
these ideas into practice, thereby opening an exciting
new area beyond what was originally planned for SLAC's
experimental program.
Ballam became Associate
Director of the Research Division in 1963. He assumed
and executed brilliantly the multiple roles of
directing the construction of a wide variety of advanced
particle detectors, making decisions on competing
proposals for instruments and experimental work, and as
an active leader of one of the research groups at the
laboratory. In the latter role Ballam initiated a
vigorous double-headed hydrogen bubble chamber program.
Under his direction a rapid-cycling 40 inch hydrogen
bubble chamber was designed and built. In a hybrid
configuration the chamber could operate in a mode in
which picture taking was triggered by appropriate
electronic detectors. He also, in cooperation with
Professor Luis Alvarez at Berkeley, arranged for the
conversion of Alvarez's 72 inch bubble chamber into a
modified 82 inch chamber operating at a higher expansion
rate, followed by a move of that chamber across the Bay
to SLAC.
The 82 inch chamber was
installed in hadron beams of many varieties and the 40
inch chamber was operated in photon beams of highly
original design pioneered by Ballam. In particular, the
conventional Bremsstrahlung beams were replaced by
monochromatic gamma rays resulting from electron-positron
annihilation, followed by an arrangement in which high
intensity laser photons were Compton back-scattered from
a high energy electron beam. The 82 inch chamber served a
wide variety of university bubble chamber analysis groups
and, in fact, developed such a high productivity that for
some time it saturated the worldwide data analysis
capacity producing as many as six million photographs per
year. The program of the 40 inch chamber in which Ballam
was most personally involved comprised studies of the
photoproduction of Vector mesons, the first measurements
of photoproduction of charmed particles at high energies,
and numerous other photoproduction studies and research.
With the advent of
colliding beam physics at SLAC, Ballam joined the MARK II
detector group when it was in process of being upgraded
from its original version used at the first storage ring
SPEAR at SLAC. He also participated with the upgraded
MARK II, when it was moved to serve as the first detector
at the SLAC Linear Collider (SLC), including studies of
the parameters at the Zo resonance, measurements of the
strong coupling constant and various particle searches.
Even after retirement,
Ballam participated personally in some of SLAC's
research. Until his death he remained an active
collaborator in the second generation gamma-ray detector
in space, called GLAST, now under active design.
In parallel with his
personal research, Ballam was an extraordinarily
effective director of the research activities at SLAC. He
established a first-rate computation department and his
counsel on computation in high energy physics was widely
sought on national committees. He assumed chairmanship of
a sub-committee of the High Energy Physics Advisory Panel
(HEPAP) for the DOE, charged with projecting the
computing needs for High Energy Physics. He counseled on
an upgrade of computational facilities at Fermilab and on
the computation needs of the SSC. Even after his
retirement Ballam continued to serve as advisor to the
director of SLAC, principally on computational matters.
Ballam greatly advanced
high energy physics through first-rate personal
contributions through his own research, largely using
pictorial techniques. He combined this work with a major
administrative role at SLAC, wise counsel to many
institutions and a gift for creative presentation
covering designated areas of the science.
Joe Ballam had the rare
and wonderful gift of gaining the respect, the
admiration, and the warm affection of his colleagues even
as he made the necessary tough decisions as SLAC's
founding Associate Director for Research. He did this by
acting decisively, retaining his kindness, his patience
and his understanding under the greatest pressures, and
never sacrificing his sense of justice and fairness. Both
winners and losers in the competition for SLAC's limited
resources remained his friends. His contributions will be
long remembered and his many friends and associates
deeply miss him.
MEMORIAL
RESOLUTION COMMITTEE:
Wolfgang K.
H. Panofsky, Chair
Sidney Drell
David W. G.
S. Leith
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